ALBEDO: Denomination that, derived of the Latin verb albeo (be white), receives the so much by one or percentage reflected of the luminous radiation incident. The albedo depends, primordialmente, of the nature of the surface receptor, angle of incidence of the solar rays and wavelength of these.
ALISIO: His etymology proceeds of the Greek word alx (sea), so that wind alisio means, literally, maritime wind; said condition finds implicit in other denominations, such as the English trade-winds, that is to say, winds of the trade, since they were those that promoted the navigation to sail until the American coasts, and the German of passatwinde, or was, winds of the travesía, with the lusitanismo passata incorporated. The alisios integrate the big east flow, that, by half term, affects a band of 25º of latitude in each hemisphere, wider during the summer and less in winter.
HIGH POLAR MOBILES: Apófisis desgajadas of the High Polar Pressures, to way %u201Cof icebergs of an inlandsis%u201D, that displace in the zone of west general circulation.
HIGH POLAR PRESSURES: The high polar pressures are centres of permanent action of raigambre thermal, formed on the polar sockets in favour of the presence of air very cold.
HIGH PRESSURES SUBTROPICALES: The high pressures subtropicales are master pieces of the atmospheric circulation general given his condition of centres of dynamic action of permanent character. In the planetary diagram of energetic balance the anticyclones subtropicales form part of the sector to greater latitude of the cell of Hadley that exerts decisive paper in the process of transfer of heat of Ecuador to Polo. They situate in a sector of subsidencia intense that imposes drought, cleared and high skies temperatruras in the distinguished latitudes. Besides they delimit the big zones of atmospheric circulation general, that is to say, mark the border between the atmospheric circulation of tropical shots and the half and high latitudes dominated by the west winds.
HEIGHT OF SOL: it Comes given by the angle of incidence of the solar rays with the horizontal. The height of the sun varies with the latitude, period of the year and hour of the day. After these modifications find the geoid, the inclination of the terrestrial axis on the plane of the ecliptic and the movements of traslación and rotation, since these two last determine respectively the succession of stations and the daily cycle. The sun, that reaches his cénit on the equator in the equinoxes and for each tropic in the solstice of corresponding summer, so only raises , by then, 23º ´ 27 in the poles, with wintry night of six months.
ANTICYCLONE: (Vineyard. Map of Time)
ATMOSPHERE: Term composed of the Greek roots atmoV (steam, smoke) and sjaira (sphere) with which designates the gaseous wrapping that surrounds a planet. The terrestrial organises in layers, more or less homogéneas, according to thermal behaviour, chemical composition and electromagnetic structure. It is a mix of gases, no a combination, since those do not react chemically between himself.
DROP OROGRAFICA: it knows also like depression of leeward, because it appears in said slope concerning the flow in whose breast is born owing to the hydrodynamic effect of the obstacle. According to Paul Queney, said process develops when the flow confronts a relief of width no inferior to 100 km. And whenever that do not drive air so unstable as to shoot in the vertical.
DROP PRESION: (Vineyard. Map of Time)
POLAR DROP: it treats of a small depression, with frequency very active, that produces preferably in winter, with a thermal gradient sea-earth very stressed. The advección, with continental origin, of arctic or polar air, and from here the name, on a marine surface noticeably less cold, ocasiona a strong inestabilización of said flow, so much by basal warming as owing to the discharge of latent energy that supposes the transfer to the same of important quantities of steam of water. The exaggeration of the static thermal gradient in the vertical favourable the development of cumulonimbos, with showers of big intensity, snowfalls, hailstorms and, in occasions, winds to big speed, that excepcionalmente surpass the 200 km/h.
DROP SUBPOLAR: Depression of origin primordialmente dynamic situated in latitudes subpolares and attributed to the hydrodynamic effect of the obstacle exerted, on a large scale, on the west general flow by a relief sinóptico. Like this, then , it treats of depressions of leeward of gigantic dimensions.
THERMAL DROP: The calificativo alludes to the mechanism, consistent in a caldeamiento intense, that dilates the air, reduces his density and causes the promotion; since the capacity of evacuation of the divergence that tops the depression surpasses the one of feeding by the convergence of surface, braked by intense rozamiento, produces in the vertical an empty relative, with descent of pressure. These depressions, carentes of frontal structure, form , preferably, during the summer, in peninsulas and islands
LOW EQUATORIAL PRESSURES: it Results preferable the calificativo of intertropicales, since said areas do not have always by axis the equinoctial line; this fulfils this paper in January, but remains backwards in the summer boreal, with maximum trip in July, when the low pressures migrate to the north a ten of degrees and, sometimes, more. Known internationally like doldrums, does not treat of spaces of strict calm, know a horizontal circulation very feeble, with horizontal gradients of pressure practically despicable.
PLANETARY ENERGETIC BALANCE: System of entrances and exits of energy calorífica, for the group of the planet and in annual average, that results of the difference between broadcasts of electromagnetic radiation of pertinent short wave of the sun and of long wave issued by the surface and the terrestrial atmosphere, measure in the external edge of the atmosphere or layer limit.
BLIZZARD: Expression originaria of the central states of United States, with which designates to the storms of violent wind and very cold, pertinent north or northwest, that transport snow, in occasions raised of a floor previously nevado.
BORA: Cold and violent wind that affects, especially, the coasts of Istria and Dalmacia, from the Gulf of Trieste to the of Medovani. It leaves feel also in New Zembla or in the coast noroccidental of the Black Sea, in Novorossiysk. It blows in winter with big violence when dawning; they are frequent speeds of 60-70 km/h, although they register , sometimes, other upper to 150 Km/h.
BREEZES: The breezes are winds of time character that blow in relation with thermal factors that modify the fields of pressure. It speaks of breeze of sea and earth (marinada or virazón and terral) when the phenomenon produce in coastal zones or islands, and of breeze of valley and mountain if the blow of this wind produces in mountainous areas.
BUYS-BALLOT, LAW of: From the consideration that the wind blows of the sectors of more pressure to the ones of less and having likewise in account the theorem on the composition of the accelerations of a mobile in a flash die formulated in 1843 by the French mathematician Gustave Gaspard Coriolis: %u201COf backs to the wind, the lowest pressure remains to the left and the highest to the right%u201D; such sucede in our hemisphere and to the reverse in the austral. According to the rule of Buys-Ballot, the wind moves in the maxima of the hemisphere north to the equal that the manecillas of the clock and on the contrary in the minima, circulating with reverse twists to the previous in the hemisphere austral.
HAZE: The haze, calina or calisma is the optical meteor caused by the presence of particulas in suspension in the air in sufficient quantity to cause turbidez. It is necessary to distinguish between the haze sensu stricto, that results of an advección of pertinent dust of arid zones, and the atmospheric situations that generate environment more or less enfoscado by accumulation of particles in suspension, of diverse origin, in conditions of subsidencia anticyclonic.
HEAT SPECIFY: it Comes given by the quantity of calories required to elevate 1º C the temperature of a gram of determinate substance. By the own definition of calorie like the necessary heat to increase 1º C the temperature of a gram of water, the specific heat of this is 1.
CLIMATIC CHANGE: The climate is, by own nature, cambiante. From the training of the Earth until the actuality the shots of the planetary climatic system, manifested in some mechanisms of atmospheric circulation that print his print in the climatic elements, has experienced alterations been due to natural causes. The solar energy that reaches to the terrestrial atmosphere experiences variations been due to astronomical factors, although the volcanic eruptions and other geographic factors are also able to influence decisively. The changes in the inclination of the axis of terrestrial rotation concerning the plane of the ecliptic, with cycles of 41.000 years, signalled by the Serbian astronomer Milankovitch, the eccentricity of the terrestrial orbit, that oscillates each 100.000 years, and the precession or twist in peonza of the terrestrial axis with regard to the ecliptic or to the rest of the stars, with periods of 23.000 years, cause variations in the solar radiation incident of the hemisphere south. In the actuality with the expression change climatic alludes to the current hypothesis of alteration of the terrestrial climate that defends the origin antropogénico of the thermal increase observed from the decenio of the seventies.
CELL OF HADLEY: In 1941 the Swedish meteorologist Carl-Gustav Rossby, member of the School of Bergen established in United States, exposed his famous model tricelular of the atmospheric circulation general, known like this for conceiving that, in the vertical plane, structured, for each hemisphere, in the polar cells, of Ferrel and of Hadley, justifying with reference to her the course of the alisios. The cell of Hadley covers, by half term, the field between equator and maximum subtropicales, exerting, in opinion of a lot of tratadistas, paper of prime importance in the transfer of energy calorífica to upper latitudes, showing particularly developed and active on the hemisphere in winter. Said cell appears configured by the flow of the alisios in surface and of the contraalisio in altitude.
CENCEÑADA: With the general denomination of cenceñada or, in some sectors of the Spanish northern Plateau, cencellada knows the hidrometeoro consistent in the training of ice, at the expense of the drops subfundidas, on the objects wrapped by the freezing fog. If these are vertical, results usual the training of plates of hard ice, to way of flags, that grow, sometimes several decímetros, in contrary direction and face to the wind that pushes to them the freezing fog. It treats of a frequent phenomenon in the high mountain; with excellent examples, for the Spanish territory, in Pyrenees, Saw Nevada and Teide; the cenceñada on the retamares of this last composes an image of singular beauty.
CENTRES OF ACTION: Configurations of pressure that have character of centre rector of the atmospheric circulation in the different terrestrial fields. In puridad this category remains reserved to those trainings of pressure that, by his degree of permanence and quality of manantiales of masses of air are, really, basic pieces of the atmospheric circulation general (anticyclones subtropicales, minimum subpolares, high polar and equatorial drops). Nevertheless with this denomination designates to any isobaric configuration with presence more or less prolonged in a region that determines the seasonal shots of the time.
CICLOGÉNESIS: It designates like this to the process by which develop depressions or ciclones (of kuklow, arremolinarse) in favour of determinate conditions of temperature (vertical thermal gradient) and atmospheric pressure (fields of pressure). The ciclogénesis has theoretical foundation in %u201Cthe theory of the development%u201D elaborated by the British meteorologist R.C. Sutcliffe, in 1947, as which in the half troposphere (600-500 hPa) exists a level %u201Cof no divergence%u201D, by on or underneath of the cual produce divergences of distinct sign.
CICLON EXTRATROPICAL: After relating, with evident tarpaulin, basic climatic parameters and systems nubosos, Jacob Bjerknes identified the surfaces of discontinuidad designated successively lines of turbonada, of convergence, course and, definitively, fronts. It conceived, like this, a depression or borrasca structured around two surfaces of discontinuidad or fronts, one previous warm and another back cold, accompanied of systems nubosos characteristic and precipitations, and animated all the group of cyclonic twist. In sum, in his phase of maturity, the ciclón extratropical, called also in honour to his discoverer, ciclón Norwegian, was represented, in what prototype, like a depression more or less circulate, in whose centre remains the vertex or point of union of both fronts. The contrasts of temperature and density, to which conceded paramount importance, were born of the pinzamiento of a central warm sector between two colds, one previous and another back.
CICLON TROPICAL: A ciclón tropical is a mobile cyclonic structure formed in the field intertropical in which they put at stake enormous quantities of energy. Some tratadistas signal that the energy set up by a ciclón tropical is able to export the excedentes energetic accumulated in tropical latitudes and balance like this the energetic balance in said field. They affect, with distinct calendar, a wide faja of earths and seas of the field intertropical.
CIRCULACION ATMOSFERICA GENERAL: The two big engines of the general atmospheric circulation are the terrestrial rotation and the solar radiation. To them, together with the distribution of earths and manres, owes the organisation of the big flows planterarios, to the equal that the presence of the centres of permanent action, cuasipermanente, semipermanentes or seasonal.
CLIMATIC CLASSIFICATIONS: The regional climatology handles systems of reference in the study of the diversity of terrestrial climates. The climatic classifications differ according to criterion and scale of work. They establish numerical thresholds that are used to to coincide with limits of biological development of plants, vegetal trainings in his group or crops or, well, are statistical frequencies of occurrence of characteristic atmospheric circulations. The proposals elaborated consider the planetary group like scale of work, without forgetting that the goodness of a climatic classification depends on the versatilidad that offer to adapt to lower fields. To tenor of the approach chosen differentiate two big groups of climatic classifications: to) the fisionómicas that combine climatic parameters, obey to criteria biogeográficos or opt by an approach of geographic synthesis and b) the genetics that consider the matizaciones that impose the geographic facts in the general atmospheric circulation.
CLIMATE: The etymology of the word is Greek (klima) and says relation with the verb klinw (bend), alluding to the inclination of the solar rays and, with this, to the length of the day, since prístinamente said voice possesses a time meaning. Since here the concept expanded his semantic field and evolved until giving fit to the distinct mechanisms, processes and atmospheric phenomena. It reached the resonance and diffusion the proposal by the Austrian meteorologist Julius von Hann (1839-1921), the one who, in his Manual of Climatology (1883), conceptuó the climate like the group of phenomena that characterise the half state of the atmosphere in a determinate point of the terrestrial surface.
EQUATORIAL CLIMATE: Designated, likewise, hipertropical, tropical always rainy or guinean climate, in the geographic classification of Viers, is the own climatic variety of earths situated in give them of the equinoctial line, with influence of the trip of the Convergence Intertropical, that crosses them twice a year and of the masses of equatorial air that generate in the commands selváticos equatorial and in the very warm seas.
TROPICAL CLIMATES: The tropical denomination alludes to the significant change (of the Greek, troph, change, alteration) that suffer, in this climatic variety, the atmospheric conditions along the year, and that allow to distinguish between a dry station and another rainy. This seasonal modification links to the swing of the Zone of Convergence Intertropical that organises the rhythm pluviométrico of the tropical climates.
TEMPERATE CLIMATES: they Are those that know the succession of own meteorological shots of the distinct stations of the year. The denomination of temperate, allusive to the thermal goodness, does not result of the all ideal, since this templanza only suits to the climates of maritime influence. In half latitudes delivers big variety of climates from the ones of winter rigorously cold of the Siberian command or yakuto to the Mediterranean of soft winters and summers very warm. The classification algebráica of Köppen matiza between temperate climates sensu stricto, in which any monthly average drop of -3º C and temperate climates colds in which some month descends of said threshold.
MEDITERRANEAN CLIMATE: temperate Climate, represented in the paises ribereños of the Mediterranean sea, of where takes his name, characterised by the drought estival, parquedad general of annual precipitations and thermal benignity. The Mediterranean, by location, is a climate of transition between the field subtropical-desértico and the command of temperate climates where, with matizaciones, these present with abundance and regularity. It is a field of theoretical balance calorífico and, precisely thus, is creditor of constant energetic transfers between tropic and polar latitudes, that reflect in the alternative game of command of the subsidencia subtropical and of advecciones of masses of polar or arctic air, in the breast of the west general circulation. Pluviométricamente The Mediterranean climate is a command of contrasts in which, under the common denominator of the shortage, present sectors really semiáridos with annual totals that do not reach 150 mm. And areas imbríferas that, in favour of the altitude and disposal of the reliefs, regiatran maximum of next quantity to the one of oceanic climates of Norwegian type (almost 5 m. In the observatory montenegrino of Boka Kotorska).
CLIMATES OF POLAR LATITUDES: The earths insert or next to the polar circles enjoy of some climatic shots characterised by the absence of meteorological summer and the more or less prolonged existence of snow and ice along the year. The delimitation of the polar climates results problematic put that the isotherm of 10º C for the warmest month proposed by Köppen does not leave to be a threshold biogeográfico of transition between the taiga and the tundra, although under this limit shut regions with annual half temperatures upper to the ones of a lot of observatories of cold temperate climate that explain between his monthly averages with, at least, one upper to 10º C. To end to avoid this contradiction Trewartha proposed that the annual average, in all they, did not exceed of 0º C, what according to this author would come to coincide with the existence of freezing floor (permafrost), question, however, no exenta of matizaciones.
CLIMATES DESÉRTICOS: With this denomination identify a variety of climates characterised paisajísticamente by the aridez. They are the dry climates, characterised in the notation of Köppen, by the capital B that accompanies of the letters S or W in function of the greater shortage of precipitations. These conditions link to the existence of atmospheric conditions of subsidencia, of diverse origin. By his territorial development, the most stood out is the subsidencia of dynamic origin related with the presence of high pressures subtropicales, responsible of the training of the rosary of deserts that surrounds each hemisphere to the 30º of latitude. To this mechanism link the climates saharianos, Senegalese and Syrians or of transition to the Mediterranean command. The subsidencias of thermal origin link to the contact of air with masses of cold water by the existence of cold marine currents and give place to the training of the coastal misty deserts Chilean-Peruvian and of Namib.
CLIMATE URBANO: The urban climate is a local climate characterised by the differences that register in the values of the atmospheric variables in the interior of the city, that supposes significant contrasts between that and the peripheral rural area. The most characteristic shot of the influence of the city in the climate is the training of %u201Cthermal islands%u201D whose exponent more representative is the %u201Cisland of heat%u201D, finish coined, in 1958, by Gordon Manley to designate to the urban area with high nocturnal temperatures with regard to his surroundings owing to the increase of artificial heat of origin antropogénico.
CLIMATOLOGY: it Knows distinct definitions. The simplest and possibly less questionable was the conceptuación of the same like science that studies the climates in his basic slopes and applied. A first big subdivision, that in past decades has been comparison, establishes between analytical Climatology and synthetic Climatology. The first, motejada by his detractores of %u201Ctraditional%u201D, %u201Cseparativa%u201D or of the %u201Caverages%u201D, disocia, for his examination, the climatic elements that in the atmosphere are interactive or interdependent, for afterwards combine the results of the analysis. The Climatology used adjectivally synthetic, procures the vision integradora and conjoint of the diverse mechanisms and climatic elements.
COLLADO: (Vineyard. Map of Time)
GROUP CONVECTIVO OF MESOSCALA: A group convectivo of mesoscala is a training nubosa of big dimensions (trascend the state of cumulus) that originates in atmospheric conditions of intense baroclinia, with high degree of internal organisation, inside the mesoscala, that does them evolve with cycle of own life, being able to, even, interact with the surroundings sinóptico and modify it. The superación of the state of "isolated" cumulus and the acquisition of dimensions of mesoscala achieves by the successive coalescence of cores convectivos of lower size that converge in a greater group in favour of determinate conditions sinópticas. The final result, identifiable in the infrared images of the Meteosat, is the apparition of areas of ingente condensation, of tonality very dark, because of the intense release of latent heat in the frame of active atmospheric conditions nubígenas. The enrome energy accumulated converts to these groups nubosos of mesoscala in one of the greater sources generadoras of rays of the planetary atmospheric system.
CORIOLIS, STRENGTH OF (call also geostrophic strength or strength desviadora of the Earth): it does not treat of a real strength, but fictitious or apparent, that enters to justify the consequences of the absolute eddy, whose existence evidenciaría, some years afterwards, in 1851, León Foucault, with his famous experiment, based in the invariabilidad of the plane of swing of the pendulum. Coloquialmente Says that the Strength of Coriolis diverts the mobiles rightwards in the hemisphere north and leftwards in the hemisphere south. Said opposition is not but consequence of the absolute eddy, whose sense of twist is contrary to the of the manecillas of the clock in the northern and satisfied hemisphere with him in the meridional. All the relative to the terrestrial surface sees solidariamente affected by said twist, are geographic coordinates or isolíneas climatic. It comes given by the formula AC=2V v sen to, being V the speed the mobile, v the angular speed of the Earth and to the latitude considered. The absolute eddy and, with him, the Acceleration and Strength of Coriolis are non-existent, with value zero, in the equator. By the contrary, the speed of the absolute eddy is maximum in the poles, where coincides with the angular of the planet; in function of this, and to equality of other conditions, the Acceleration and Strength of Coriolis result likewise maximum to 90º of latitude.
CURRENT IN CHORRO: The currents in chorro are basic pieces of the planetary atmospheric circulation, in particular, of half and high latitudes. The World-wide Meteorological Organisation defines them like %u201Ca strong and narrow current, concentrated along an axis cuasihorizontal in the high troposphere or in the stratosphere, characterised by strong vertical gradients and sides in the wind speed and one or more maximum of speed%u201D. A current in chorro has a length of several thousands of kilometres, a width of cientos of kilometres and a thickness of several kilometres. The vertical gradient in the wind speed is in the order of 5-10 m/s. By kilometre and the side of 5 m/s by 100 km. The current in chorro presents centred on a line of maximum speed of wind, at least 100 km/h in his axis, that surpasses, with frequency, the 300 Km/h.
MARINE CURRENTS: Circuits of oceanic flow that transport mass, energy and chemicals and nutritious to big distance. His origin relates with the existence of two types of strengths, the primary, that promote the waters linked to the systems of pressure and winds and the game combined of temperatures and salinity, and the secondary, that modify the speed and direction of the movements of the currents, between which projects the strength desviadora of Coriolis.
CURVE OF STATE: For the knowledge of the conditions of stability or atmospheric unsteadiness result indispensable the thermal data that, contributed by the radiosondeo, allow to trace the designated curve of state; this evidence the static thermal gradients in the vertical or existent real gradients, of main interest to value those. The curves of state present, like paramount anomalies, thermal investments and exaggerations of real gradient; the first favour the stability while the second propician the unsteadiness.
DEPRESSION: (Vineyard. Map of Time)
DORSAL: (Vineyard. Map of Time)
EFFECT FOEHN: it calls like this to the phenomenon that causes increase of temperature and decrease of the relative humidity in the wind that crosses mountainous accidents of entity. This process causes accused disimetrías pluviométricas between the slopes of windward and leeward.
EFFECT INVERNADERO: In the analysis of the planetary energetic balance (vineyard.) It has signalled the importacia that has the flow of energy in shape of long wave that receives the pertinent terrestrial surface of the troposphere by effect of the radiation effected by the clouds that, to said effects, act like black bodies and by absorbent gases like the steam of water and carbon dioxide, among others. Of not existing the clouds and these gases of effect invernadero the effective temperature to which the system Tierra-atmosphere finds in balance of radiation would be of -18º C instead of the +15º C current. This difference is the designated %u201Ceffect invernadero natural%u201D, that does habitable our planet to similarity of the confort thermal that register the plants in an invernadero. Distinct question is the increase of this effect invernadero natural by effect of the broadcast antropógena of determinate gases, process in which it supports the current hypothesis of climatic change.
ENSO: The acronyms ENSO, do reference to the phenomenon that takes place by conjunction, some years, of the maritime episode of %u201CThe Boy%u201D and a negative phase of the Swing South (Southern Oscillation) in the Pacify Meridional. It is necessary to require that %u201CThe Boy%u201D, like maritime event, is a fact that occurs, every year, in front of the peaceful coasts of Peru, known from does centuries by the fishermen of said field that identify it with the apparition, in dates navideñas (from here the name of %u201CThe Boy%u201D, in honour to the Boy God), of warm waters sea inside in a sector visited by the cold current of Humboldt or of the Peru, rich in nutrients that feed the phytoplankton and favours the presence of rich pesquerías of anchoveta. The arrival of these warm waters in Navidad impoverishes the content of nutrients causing the fall of the activity pesquera. This warming does not trascend the north of Peru and to March-April (Saint Week, following the religious calendar) go back the cold waters to occupy the marine surface. Nevertheless, some years %u201CThe Boy%u201D comes with intensity redoblada rebasando the limits space-distinguished storms, so that the warm waters occupy a wide sector of Pacífico Equatorial and remain in this state a year or more. Then they register upper temperatures to the usual, intense rains and floods, that is to say, an accused environmental change, with repercussions very negative for the chain trófica generated at the expense of the current of Humboldt, when originating ingente mortandad of plankton, grave damages to the pesquerías and big mortandad of aquatic birds.
HOARFROST: When the rocío produces to inferior temperatures to 0º C hiela, giving place to the hoarfrost, pink or white frost, so striking on the plants, where finishes by helarse his own transpiration. With thermal registers by low %u2013of 10º C the white frost produces by the direct transformation of the steam of water in ice, by means of the designated, improperly in this case, sublimation, without that it mediate the process of condensation.
ATMOSPHERIC STABILITY: The situations of atmospheric stability obey to dynamic factors or condicionamientos thermal, that can act likewise jointly. The subsidencia, that translates in atmospheric stability, can have dynamic or thermal causes.
ETESIOS: The etesio or eteciano is a cool and dry wind north that blows in the Mediterranean oriental, especially in the sea Egeo, during the summer, between May and September. Main shots of these winds are his constant direction and persistent speed; his blow is in relation with the presence cuasipermanente of low pressures in the north of Africa, because of the intense caldeamiento in this period of the year.
EVAPORATION: Vaporisation of a liquid without ebullición. This process reviste singular climatic transcendence on the oceans, transferring to the atmosphere quantities ingentes of steam of water, that is to say, the water and the latent energy embezzled to the liquid evaporante. In favour of the evaporation play dry air to high temperature, water warmer that that, wind and atmospheric pressure drop.
EVAPOTRANSPIRACIÓN: Transfer of steam of water to the atmosphere by a surface with vegetation, like result of the conjoint action of direct evaporation and transpiration of the plants.
FOEHN: The foehn or föhn, is a wind of meridional component that affects the Swiss Alps and Austrians, and that, when moving them, turns into a katabatic wind that descends drier and warm that began the promotion. It purchases his name of the Austrian place situated in the northern slope of the Alps of Seetaler and comes from of the Latin word favonius (light and warm).
FRONT: The contribution more señera and valuable of the School of Bergen to the meteorological science is the description and representation of the image of the ciclón extratropical or Norwegian, realised by Jacob Bjerknes in 1919. After relating, precisely, basic climatic parameters and systems nubosos, said researcher arrived to the conclusion that two surfaces of discontinuidad, that is to say, a previous warm front and a back cold front structured the borrasca. In effect, the referred surfaces of discontinuidad called, successively, lines of turbonada, of convergence or course, finished for receiving the denomination of fronts, like resonance and memory of the war of trenches that had characterised the first world-wide conflict.
POLAR FRONT: Concept billed by Jacob Bjerknes and Halvor Solberg in 1920, arisen in the research of the origin and evolution of the borrasca until reaching his phase of maturity, as well as the back stadiums. The Norwegian meteorologists observed the apparition of a new borrasca on the cold front of the precedent, and this suggested them the idea of the Polar Front, when supposing that the warm and cold fronts of the ciclón extratropical were not but segments of a discontinuidad main, between the polar and tropical air, the designated Polar Front, whose unsteadiness, through successive ondulaciones, would give birth to the families of borrascas.
DROP FRIA (kaltluftropfen): marked Depression, non-existent in surface and only perceivable in the upper levels. The essential shots of %u201Ca cold drop%u201D are the following: 1.Existence, at least, of an enclosed isohypse in the absolute topography of 500 hPa. 2. The air to less temperature comes to coincide with the core of the depression in altitude. 3. It is not requirement that the analysis in surface show an anticyclonic situation, and neither has to consider exceptional that, in the floor, finish appearing a drop, reflection of the existent in the upper levels; instead, yes it has to suceder that the depression in surface result little deep and the feeble cyclonic circulation. 4. There is the one who, like Llasat, demands the presence of an enclosed relative isohypse in the thickness of 500/1.000 hPa. The apparition of %u201Cthe cold drop%u201D results of the replacement of the zonal circulation by one more or less meridian, with clear tendency to end in situations of fragmentation or blockade, that answer to two types: %u201Cthe one of ondulación or in omega%u201D, that results of the coalescence of anticyclonic crests by a process repeated of estrangulamiento of vaguadas, that finishes for generating a big anticyclonic construction, reflected in surface by the presence of a big anticyclone of blockade that hampers the west circulation; the another modality of blockade, with apparition of %u201Ccold drop%u201D or drop given off in altitude is the designated %u201Cin rhombus%u201D , dipole or with bifurcation of the current in chorro.
GRADIENT: it understands by gradient the difference between the registers of a climatic element to the space distance established. Without that they are missing others, the climatic gradients more usual and spread atañen to atmospheric pressure and temperature. The horizontal gradient of pressure comes given like the difference of pressure by degree of meridian or segment of sixty marine miles, distance measured on the perpendicular to the infinitesimal portions of two consecutive isobars, that, to said effect, consider rectilinear; it expresses , usually, in mb. Or hPa./111 Km. It exists also the called barometric gradient of height, that measures the metres of promotion until the atmospheric pressure reduces 1 mm. Hg, that is to say, 1,3 mb. Or hPa. The horizontal gradient of temperature, particularly important to evaluate the desfase of that between earths and seas, by the thermal inertia of the marine waters. For the plane or vertical handle the concepts of gradient of half state, real gradient, adiabatic gradient and gradient pseudoadiabático.
FROST: atmospheric Situation that causes descent of temperatures to next or inferior values to the freezing point of the water. The frosts produce , in favour of continentalización, in days of cold nocturnal in favour of an intense loss of heat by irradiation, in wintry days with powerful anticyclone with origin of hoarfrost. Self-evident by the origin of hoarfrost.
ATMOSPHERIC HUMIDITY: The steam of water is colourless and his density 5,8 upper times to the one of the air. Incorporated to the atmospheric mass by the processes of evaporation and transpiration, the steam of water forms part of the atmospheric mass with upper percentages to 0 and inferior to 5. His presence possesses singular meteorological transcendence, and no only because to his expensas generate the distinct hidrometeoros, but had to also to his exceptional leadership like thermal regulator, owing to his extraordinary capacity so much to absorb the solar radiation as to retain the reenviada by the terrestrial surface. Said function reduced to the minimum, by his ínfima presence, in determinate deserts subtropicales (Sahara, Arizona, among others), ocasiona very high temperatures during the day and intense nocturnal coolings, with brutal daily thermal swings, that exceed the half hundred of degrees centígrados. By all this, the measure and study of the steam of water reviste the greater interest. For said aim employ a series of instruments (hygrometers, higrógrafos, termohigrógrafos, evaporímetros, psychrometers) and handle a group of concepts, such like absolute humidity, specific humidity, relation or proportion of mix, pressure of steam, relative humidity, curve of saturation that's that of rocío.
ATMOSPHERIC UNSTEADINESS: Situations originated by dynamic mechanisms or condicionamientos thermal, in occasions combined.
INSOLACIÓN: To spite of the very high temperatures that reign in the interior of the Earth, the geothermal contribution to the temperature of the air, since the roquedo is an abysmal driver, results desdeñable. The big source of energy calorífica is the sun. And in relation with this handles the concept, evidently improper, of solar constant, considering like such the solar radiation received in the limit of the terrestrial atmosphere, to the half distance between the sun and the earth, by a perpendicular surface to the solar rays (layer limit), enciphering that in 2 Ly/min., that is to say, 2 cal/cm2/min. Neither that say has to the solar constant is non-existent, by what the solar radiation before penetrating the terrestrial atmosphere remains supeditada to the own solar activity and to the own eccentricity of the terrestrial orbit around the sun. Theoretically, all the points of the terrestrial surface have the same number of hours of sun (4.380 annual hours), so much in the equator (365 * 12) as in the poles (365/2 * 24). The reality is very distinct, with the conditioning of the cloudiness in first term. To the hour to explain the strong contrasts in the contributions of energy calorífica have to have very in account, the quantity of radiation by unit of surface and the losses registered when crossing the atmospheric mass.
FLOOD: Overflow of a fluvial course motivated by the development of intense precipitations, fast fusion of snow or break of reservoirs, by diverse cause. The floods of natural origin owe his origin to abundant rains originated by ciclones tropical, precipitations monzónicas or storms convectivas in the field intertropical and to storms of rain, of diverse origin, in half latitudes.
THERMAL INVESTMENT: it Involves an alteration of the curve of state, consistent in that it appears air to more temperature that the infrayacente, investing the normal sequence of this with the promotion. They are varied the modalities and causes of the thermal investments.
ISOLINEAS: The cartography of meteorological and climatic elements serves , like basic instrument, of distinct isolíneas, built all they at intervals fixed. The most ancient is the isotherm.
RAIN OF MUD: Known also like rain %u201Cof fango%u201D, rains %u201Cof dust%u201D (%u201Cdust rain%u201D, in English) or rains %u201Cof blood%u201D, is a hidrometeoro peculiar formed by drops of condensed waters in sands and silts that act of core of condensation of the steam of water; evaporated the water of the drops, the cores of sand or silt tapiza the surfaces with a fine layer of ochre or reddish tonality, very striking in the windscreens of the cars of dark colour.
MAESTRAL: Designated likewise mestral, mistral, minstral or master (of the Latin, magistralis), treats of the wind of the northwest, cold and dry, that blows, preferably in winter, with sky cleared, and affects, especially, the Gulf de León and the northern area of the Balearic archipelago. With frequency reaches speeds of 80-100 km/h. And , in occasions, duplicates them generating sea arbolada or of very grave danger. Said speeds result disproportionate to the horizontal gradients of pressure imperantes, and are possible by the intervention of other mechanisms. It proceeds of the accumulation of cold and dense air in the basins of the Alps or mountains Cevennes or of the presence of high pressures in the northwest of Europe.
MAP OF TIME: Source of basic work for the climatology and, in particular, of his branch sinóptica is the cartography of the systems of pressure to different altitude. The term sinóptico, of the Greek sunoyiV, means "overview or understanding"; and, in effect, the maps of time offer a global vision of the meteorological appearances that characterise the atmospheric time in a territory. The first meteorological cartographies elaborated in the first decenios 19th century by Brandes (1820), Redfield (1825), Henry (1849) and Him Verrier (1854), but will be in the second half of said century when the regular edition of maps of the time (daily bulletins) reach diffusion thanks to the publication of bulletins to charge of the national meteorological institutions and his inclusion in some períodicos of prestige. In France the international meteorological Bulletin of the Observatory of Paris would include, from 1863, the edition of a letter of isobars in Europe. To this initiative added other countries, between them Spain in 1893.
The maps of time improved his preparation considerably thanks to the meteorological discoveries of the meteorological School Norwegian of Bergen, with his contributions on the fronts and the characterisation of the masses of air. To this will join the regularity in the meteorological observations of altitude to split, especially, of the second world-wide bellicose conflict and, from the years fifty, the consolidation of world-wide networks of radiosondeo.
The meteorological bulletins newspapers include, beside tables with analytical data of the main observatories of each country, analysis of surface, topographies of the half and upper troposphere, and, in some cases, climatic maps (temperatures and precipitation) and curves of state with data of radiosondeo. The current meteorological cartography results very varied in virtue of the simbología handled, of the scale of work and of the surfaces of representation that integrate a daily bulletin.
A meteorological bulletin newspaper composes of maps of surface, maps of altitude and maps of height. The first are cartographic representations that contains the disposal of the fields of pressure to level of sea (that is to say, to 0 metres). The configurations of pressure comes drawn by some lines (isobars) that join the geographic points with identical atmospheric pressure (measure in mb or hPa.). A map of altitude is a topographical map of surfaces of equal atmospheric pressure in which they reflect the topographical figures that derive of the presence of one or another mass of air in a concrete isobaric surface. These topographical figures come designed by the outline of lines of equal altitude (isohypses). They elaborate topographies of 850, 700, 500, 300, 200 and 100 hPa. A map of height is that whose lines join the points of equal thickness between two isobaric surfaces to distinct level. The lines of representation are, in this case, lines of thicknesses that join the points in that the thickness of the stratum comprised between two isobaric surfaces is the same. They designate also "relative topographies" put that the lines with which trace are also lines isohypses (points of equal height), but in this case the level of base is not the level of the sea (0 metres) but the altitude to which situate the isohypse of the isobaric surface more next to the floor. These maps of height or thickness are very useful for the meteorological prediction when delimiting sectors with identical "thermal wind", fictitious wind (can not measure with an anemometer) obtained mathematically that arises, when it is distinct the half density in columns of air juxtaposed, precisely to treat to equalise the half temperatures of the same. The maps of height that include with more frequency in the meteorological bulletins are the thicknesses of 500/1000 hPa and of 500/850 hPa. The climatic interest of these maps roots in that in them appreciates of clear form the thermal shots of the mass of air that affects to a determinate geographic field. The simbología employed to determine this category are the letters F (cold) and C (hot) or, in English, C (cold, cold) and W (warm, hot). It suits not confusing the concepts altitude and height in the comment of map of time. It results a forget frequent to employ the expression "map of height" to refer to the maps of 500 or 300 hPa that include in the meteorological bulletins when the correct is to designate them "maps of altitude" put that are elaborated having like point of reference the level of base 0 metres (level of sea).
In the maps of time, of surface and altitude, isobars and isohypses appear associated drawing characteristic configurations. Like this, in the absolute and relative topographies the existence of indexes of zonal circulation heights or basses been due to mechanism of planetary energetic readjustment perceive in the representations of a map of time. Like this, a situation of high index of zonal circulation reflects in the maps of altitude with the existence of isohypses that visit the scene sinóptica had of west to east. It is what knows like circulacion zonal (high zonal index) or west circulations. In these cases, the current in chorro circulates in the sense of the parallel geographic without manifesting, hardly, sinuosidades. By against, a situation of low zonal index self-evident in the maps of altitude by the existence of isohypses that have lost his zonal route and present sinuosidades, of elder or lower degree, that convert the flows in meridians (that is to say, isohypses and current in chorro circulates in sense of the meridians, north-south or south-north). It is what calls circulacion azonal or meridian. This second circulatory type conditions the apparition of the following topographical figures in relation with the mass of existent air in his breast:
-Vaguada Or planetary valley: topographical Configuration no enclosed that determines in our hemisphere meridian circulations of masses of air of felt north-south. The masses of air whose expansions generate vaguadas are the masses of polar and arctic air. When treating of masses of cold air, the topographical configurations of vaguada are fields of low pressure that come represented in the absolute topographies with the letter B and in the maps of thickness with the letter F (cold) or C (cold). The axis of the vaguadas can adopt diverse sense in virtue of the value of the indice of zonal circulation, so that it results meridian (N-S) with low index, purchasing disposal cuasi-parallel (NE-SW) when the speed of circulation of the current in chorro falls underneath of 70 Km/h, that is to say, with zonal index very low. In this last case, the waves of planetary circulation experience retrogresión, that is to say, move westward, in place of eastwards following the guidelines of normal atmospheric circulation of the half latitudes (zone of west circulation).
-Drops frias, drops given off in altitude, cold depressions in altitude, or embolsamientos of cold air desarollados in the breast of a vaguada by seclusión of one or more isohypses (vineyard. Cold drop).
-Crests and dorsal or topographical areas no closed of high pressure formed by expansions of masses of warm air to upper latitudes. The masses of air that go in at stake to generate these configurations are the tropical maritime and the tropical continental. These figures suppose meridian path of flows in felt SOUTH-NORTH.
Configurations of enclosed pressure, in surface or altitude, are the anticyclones and the low pressures. It speaks of high pressures, maxima or anticyclones to designate a configuration of isolíneas such that the highest values situate in the centre, and therefore diminish to the periphery. The presence of this enclosed isobaric unit indicates placing in the centre the sign + or letters (To, H). Instead, it speaks of centre ciclonal, area ciclonal enclosed, depression or low pressure, when the pressure grows to the periphery and decrece to the centre. It places in the centre the sign - or the initials D, L, T or B.
The analyses in surface offer, besides, a series of open isobaric units, so much of high as of low pressure. The ones of high pressure are the dorsal or crests, that sometimes, sharper, designate coin. The dorsal can appear like such open unit of high pressure without more or like prolongation of a maximum. Open isobaric configurations of low pressure are the talwegs, with axis of variable position and training linked to warmings very intense of the terrestrial surface with loss of density of the air and, therefore, descent of pressure.
Pertinent term also of the topography is the one of collado, that serves to designate the isobaric configuration constituted by isobars no enclosed and a typical form of chair to mount, product of a disposal in cross of two anticyclones and two borrascas. If the axis that joins the anticyclones is dominant speaks of anticyclonic bridge, and, if it is it the one who joins the borrascas, of desfiladero of low pressures.
It speaks of barometric marsh or marasmo, to refer to a situation characterised by the presence of isobars very distanciadas, with next values to the of the normal pressure. It treats of an area of calm, practically without winds; from here that also, of inaccurate way, employ for barometric marsh the term of would calm, that alludes precisely to this circumstance of atmospheric calm, employing the name of calmería when the fault of wind produces on a marine surface. It is a configuration that self-evident with a lot of frequency on the Mediterranean Western and the Iberian Peninsula during the summer. His presence links with the implantation of the diet of breezes.
It designates parallel isobars to the do long and very established of willing isobars one beside another in the sense of the parallel. It is the configuration of own surface of days with intense zonal circulation in the high layers of the troposphere. The greater vicinity of the isobars supposes increase of the horizontal gradient of pressure and, therefore, greater speeds of winds.
In the maps of hemispherical surface of the meteorological bulletin European can effect the follow-up of atmospheric phenomena of latitudes intertropicales that come represented with simbología specific. In this sense, stand out the following: Ciclón tropical: enclosed isobaric Configuration of very low own pressure of the field intertropical.That come represented by a blackhead (white point, but has reached the degree of maturity) with two sails oriented in the sense of twist of the vórtice cyclonic. Beside this symbol adds the name that receives each ciclón tropical according to the system of denomination been still in each oceanic region and Zone of Convergence Intertropical (ZCIT) or band of clash of the winds alisios of variable position along the year and to which associates a band nubosa. It represents by two parallel lines joined between if, to way of willing stairs in sense of the parallel.
In Spain, the first meteorological bulletin dates of 1 March 1893, edited, then, by the Meteorological Central Institute, antecedent of the current National Institute of Meteorology. The meteorological Bulletin that edits, at present, said Institute, includes three analyses of isobaric fields in surface (to 12 h. And 18 h, T. M.G. Of the previous day and to 6 h. T.M.G. Of the day in course), and diverse topographical cuts of the troposphere, to 12 h. (T.M.G.), that incorporate isotherms at intervals of 4 º C: topographies of 850, 700, 500 hPa and 300 hPa, in this last draws the current in chorro with intense black stroke. The bulletin complete with the leaf of analytical data that includes values of the thermal registers (maximum and minimum), precipitations accumulated and hours of sun of the stations of prime importance tuteladas by the National Institute of Meteorology. The projection of cartographic representation is the estereográfica polar with maps to scale 1: 40.000.000.
MARASMO (Vineyard. Map of Time)
MASSES OF AIR: Expression coined in the years twenty in the breast of the School of Meteorology of Bergen to designate to a portion or volume of air that occupies an extensive territory, with big homogeneity in his thermal shots and higrométricos in origin and capacity to modify the characters of the atmospheric time of the regions that interests.
METEOROLOGY: In his simpler meaning and immediate, Meteorology is the science that treats of the meteors, word this of Greek etymology (metewroV) that means, literally, high or elevated in the air.
ELECTRICAL and OPTICAL METEORS: In the atmosphere take place a series of phenomena linked to the electrical energy, of distinct sign, that generates between earth and clouds of development or in the interior of these; and, likewise, produced by phenomena of reflection, refraction and diffraction been due to the interposition of particles, of diverse nature, in the path of the solar rays. Between the electrical meteors the most stood out is the ray (of the lat. radius, ray of light) or electrical spark produced by the download that takes place between two clouds or between cloud and Tierra. The thunder or noise of the ray. Since the speed of propagation of the sound is of 340 m/s, in front of the one of the light, 300.000 Km/s, the thunder perceives subsequently to the destello luminous of the lightning. Between the optical phenomena projects the rainbow or arch of Saint Martín, consistent in the apparition of a semicírculo luminous, of big dimensions, in which they are represented all the colours of the visible spectrum. The name does allusion to Iris, messenger of the gods in the Greek mythology, that represented dressed with a chal of seven colours. The phenomenon observes when it rains in the part of the opposite sky in the sunlight, in front of the observer, fulfilling whenever the centre of the arch, the eye of the observer and the Sun find ranged. The halo (of the. gr. hlioV, sun. HlioV, god of Sol) is a luminous circle that surrounds in the sunlight or the Moon, generally whitish, because of the refraction of the rays of light through the cristalitos of ice of cirros and cirrostratos. Optical phenomenon is the mirage (of the lat. speculum, mirror) or illusion been due to the refraction of the luminous rays in the atmosphere.
MODELS OF CIRCULATION: it is not possible to allude here to the numerous models of circulation formulated since, more than three hundred years backwards, the famous English astronomer Edmond Halley published, in 1688, his famous map of winds to scale world-wide, accompanied of a series of considerations about the equatorial calms, monsoons and equatorial chimney. Like this, then , we will refer us to the most spread. In 1735, George Hadley included in his Philosophical Transactions a diagram of atmospheric circulation general, to tenor of the cual the winds circulated of north to south in the northern hemisphere, doing it for the austral in contrary sense; the westward deviation of the alisios would be been due to the difference latitudinal of speed líneal of the terrestrial rotation, maximum in the equator, so that the winds directed to the same would remain retarded, originating a flow of contrary sense to the of that. A century afterwards, in 1836, Heinrich Dove questions the model of Hadley and proposes another alternative, whose justification roots in a mechanism of constrastes thermal between poles and equator, of this nature would be likewise the seasonal periodicity of the monsoons, conceived like a gigantic system of breezes. Similar are the conclusions to that arrives, in his Physical Geography of the was and its Meteorology (1855), the marine and oceanógrafo American Matthew Maury. Of both disagrees William Ferrel, the one who, the year 1856, bills his spread law that, owing to the terrestrial rotation, any body that move freely is displaced rightwards in the hemisphere north and to the left in the austral; it would be, therefore, the strength desviadora of the Earth the one who would mark the courses of both alisios.
The considerable progresses of the dynamic meteorology in the last chamber of the centuria precedent and the current translate in the preparation of new models. Like this, the one of Guldeberg-Mohn (1875) looks for the explanation of the atmospheric circulation general in an approach that great mechanical laws to the engine termoconvectivo. More innovative results the because of the chair of Physics in the university of Berlin Hermann von Helmholtz, the one who established the principle of conservation of the energy and the laws of the eddies in the fluids. Already in the current century, Jacob Bjerknes, member destacadísimo of the School of Bergen, that in 1919 described and represented the ciclón extratropical or Norwegian, proposed a diagram of general circulation that, besides, to include the polar Front, concept coined by the same and Halvor Solberg, prefigura some shots of the famous model tricelular of Carl-Gustav Rossby (1941). East possesses the undoubted merit to constitute a conjoint synthesis of the zonal and meridian circulations, differentiating in each hemisphere the cells of Hadley, Ferrel and Polar. The axis of said model roots in the continuous interaction between flows and centres of action, supeditada to thermal and dynamic factors; some years afterwards would be reviewed by the own Rossby, the one who, together with his disciples of the School of Chicago did a remarkable contribution to the study of the jet-stream, whose existence was verified with reason of the II World-wide War. Elaborated after the detection of the temperate jets and subtropical, the model of Palmen (1951) includes both, doing them coincide with both breaks of the tropopause. Three lustros afterwards, and from the diagrams of Scherhag, Mintz and Dean and of the vertical courts of Riehl, Pédelaborde traces a model of atmospheric circulation general to 5 km. Of altitude, that takes into account so much the configuration of the field of resultant pressures of the distribution of temperatures like the laws of the absolute eddy and the principle of conservation of the moment of rotation around the axis of the poles. His diagram shows, like basic shots, the big zone of west general circulation, limited by the jet subtropical, and a cellular circulation in the field subtropical. Big similarity with this saves the been due to his disciple Pierre Pagney, that stands out l paper of the maxima subtropicales like master pieces of the general atmospheric circulation. The advances registered this last chamber of century in the knowledge of the atmospheric circulation general, with the important contribution that represent the images of the polar meteorological satellites and geoestacionarios, have been collected in the current diagrams. Like this, Meehl (1987), that adds to the polar west jets and subtropical, one equatorial give east on the hemisphere north during the summer boreal, underlines the paper of the cell of Hadley in the transmission of energy to upper latitudes, doing notice his hipertrofia during the corresponding winter.
MONSOONS: Monsoon, means in Arab (mausim) %u201Cstation%u201D, and with this term the navegantes of the Indicate alluded to the gigantic investment of winds that, with seasonal character, takes place in said ocean, base for the navigation between the coasts of Africa and the Indian: in summer course to the noreste (monsoon of summer or monsoon of the rains) and in winter to the southwest (monsoon of winter or dry monsoon). The classical work of Chromow on the monsoon (1950), identified like areas monzónicas those in which the wind direction in surface experiences a change of course of, at least, 120º in the transcurso of the stations of the year. Like this, it speaks of circulations monzónicas for the south and sudeste of Asia, south of the archipielago Japanese, surroundings of the Gulf of Guinea and north of Australia.
The cause last of the estacionalidad monzónica, roots, according to Webster, in the processes of readjustment of energy calorífica that produce along the year between Ocean Indicate and Asian continent.
FOG: Hidrometeoro in surface or a short height that, integrated by crowd of gotillas of ínfimo size, reduces the visibility to a kilometre. With this common denominator, the banks of fog offer, nevertheless, diversity of thickness, intensity and persistence, as well as in his causes. A summary classification of these differentiates fogs of radiation, advección and frontal.
NIEVE: solid Precipitation, formed by glasses of hexagonal symmetry. Indispensable premise of the same is that the gotillas sobrefundidas, thanks to the presence of abundant cores of freezing, go in in phase of ice and that the isoceros remain very low, so that the snow does not found in his fall; if the temperature is upper to 0º C, the snow no cuaja in the floor.
NORTH: The north or norther is a cold regional wind that blows, during the winter, in the Gulf of Mexico, when they take place invasions of continental polar air pertinent of the northern earths of United States and Canada.
CLOUDS: The apparition of clouds supposes the transformation in water or ice of steam of water; there is, in effect, clouds of liquid water, of ice and also of mixed character. This diversity of states corresponds with the one of his processes causantes, that is to say, condensation, sublimation and freezing.
The method taxonómico that uses is the proposal of Ralph Abercromby and H. Hildebrand Hildebrandsson, adopted in 1896 by the International Meteorological Organisation. They identify four morphological types and six combinations between them; in total, ten, grouped, attended the basal altitude of the clouds, in four families. The four morphological types basic are: Cirrus (clouds deshilachadas, filamentosas, fibrous, very white, without shadow); Stratus (clouds without forms differentiated, in stratum, layer or veil); Cumulus (clouds of rounded and globular peaks, very recortadas, with shadows) and Nimbus (shady and amorphous clouds, with precipitations). By means of the ascription to families, differentiate four groups, that is to say, high clouds, half clouds, low clouds and clouds of vertical development. Forms, dimensions and general configuration allow to distinguish species; like this, in the case of the gender Cumulus, differentiate Cumulus humilis, Cumulus mediocris, Cumulus congestus, Cumulus calvus, Cumulus capillatus, etc. Appearances more detailed of forms, appendices or ways in that they intercept or allow the step of the luminous radiation, allow to establish the varieties. Special quotation has to do of clouds associated to orographic accidents, designated flags, capuchones, monteras or touch, in whose development collaborate effectively the breezes of diurnal valley, that attaches them to said reliefs, while they separate them or disocian of the same the downward, especially those that blow when dawning.
WAVE OF HEAT: Type of time characterised by the sudden elevation of the thermal registers, that tornan extreme in the maximum. Although the expression has done fortune between the big public, results more appropriate the term advecciones of warm air, or hits of heat, allusive to the genetic cause that originates them and the short length that are used to to have. Hits of heat have by cause the arrival of tropical air and, in puridad, of the mass of continental tropical air to upper latitudes to the ones of his manantial and although they develop , preferably in summer, station in which the values of maximum temperature shoot , in half latitudes, above the 30º, reach and, even, rebasan the 40º C, advecciones of tropical air can cause sudden elevation of thermal registers in any period of the year.
WAVE OF FRIO: Type of time characterised by the environment helador, with thermal registers exiguos that can accompany, in occasions, of snowfalls copiosas. With greater precision has to speak of advecciones of masses of cold air or very cold, since this is the meteorological mechanism that generates them. In the hemisphere north, the waves of cold have his main period of risk between mediated of the months of November and March, with apex in January-February, interval in which polar and arctic masses reach thermal values minima in his manantiales that keep, to a large extent, in his trip to temperate latitudes. The advecciones cold, affect to a wide territory, the one who remains under the effect of the vaguadas installed in the high layers of the troposphere and ocasionan grave damages in the agricultural activity when causing the bajísimas temperatures destrozos in crops of season by freezing.
WAVES OF ROSSBY: To finals of the years thirty of the century twenty, the Swedish meteorologist, established in the United States, Carl-Gustaf Rossby signalled the existence of some patterns of movement in the atmospheric circulation of altitude in the zone of west circulation, that designated %u201Clong waves%u201D or %u201Cwaves of Rossby%u201D, confirmed, subsequently, by the observations aerológicas and the hydrodynamic experiments realised with a disk giratorio heated in his edges by Fultz, in 1949. It treats of a pattern of behaviour of the west circulation, whose operation depends of the value of the zonal index (or number of Rossby) of said common. The behaviour of the waves of Rossby is decisive for the circulation of altitude in half and high latitudes; and what is more important, today knows that the location and amplitude of determinate configurations of surface, in half and high latitudes, are governed by the waves of Rossby.
EAST WAVES: In the breast of the flow of the alisios develop , in determinate atmospheric conditions, perturbations that, hardly perceivable in the analyses of surface, adopt the form of vaguadas open to the equator, of scarce amplitude, and accompany of rainy time. It treats of waves formed on the oceanic surfaces (Atlantic, Pacífico and Indicate) that displace of east to west (from here his name), with half speed of 20 Km/h. And some dimensions of until 500 Km of length. His origin relates with momentary modifications of speed and direction that take place in the breast of the winds alisios that circulate by the sector to lower latitude (10-15º) of the high subtropicales, where the intensity of the subsidencia is lower.
WEST WAVES: The west waves (westerly-waves) are atmospheric perturbations that affect the field intertropical and cause bad time with showers copiosos. They originate by installation of a vaguada of cold air in upper levels, that propagate of west to east, from here his name; this originates strong atmospheric unsteadiness, accused exaggeration of static thermal gradient in the vertical and the additional presence of a mechanism of divergence by difluencia in altitude.
ORGANISATION METEOROLOGICA WORLD-WIDE: Organism intergubernamental that, in the breast of the UN, is commissioned to improve and spread the investigation and knowledges of the state and behaviour of the atmosphere and the terrestrial climate.
OZONE: Variety alotrópica of the oxygen, of formula Or3, that forms part of the air. In sufficient quantity, poseé blue colour, strong smell, can oxidant very upper to the of the oxygen and a big capacity of absorption of the ultraviolet radiation.
OZONÓSFERA: Subcapa Of the stratosphere, extended between 15 and 40 Km. Of altitude, that shuts 90% of the atmospheric ozone, with maximum concentration to 30-40 kilometres. Thanks to the capacity of the ozone to absorb the ultraviolet radiation, the ozonosfera constitutes a protective filter of the life on the Earth, that of another way would not be possible by the enormous power actínica of said rays.
BAROMETRIC MARSH (Vineyard. Map of Time)
PRECIPITATION: The precipitation (of Latin praecipito, precipitate, do fall) is the hidrometeoro formed by particles of water, in liquid state or solid, that, crystallised, fall from a training nubosa and reach the floor. It is used to to establish a distinction between vertical precipitation and unseen precipitation, improperly designated, horizontal constituted by the condensed water in fogs, mists, rocíos or hoarfrosts that deposits on a surface without that it mediate fallen from a cloud. The example prototípico are the unseen precipitations contributed by the cocimbos, camanchacas and cacimbos linked to the presence of the cold marine currents of Humboldt and Benguela.
PREDICCION METEOROLOGICAL: Without desconocer precedents sumamante valuable and indispensable, the birth and organisation of the meteorological prediction are referibles to the second half of the 19th century. In tightened synthesis, milestones very notorious are the following: the tempestad of 11 November 1854, that, to the desbaratar a fleet combined anglo-frank-Turkish and piamontesa that operated against the Russians in the War of Crimea, carried to the Greater State Group to pose to Him Verrier if, with the existent meteorological knowledges, those could have been foreseen and the disaster avoided; it remained like this very patent the singular strategic interest of the meteorological prediction. In narrow relation with this presupposes , in 1859, with occasion of the meeting of the Royal Meteorological Society celebrated in Aberdeen, under the presidency of the prince spouse Alberto of Sajonia-Coburgo, the use of the telegraph for the transmission of meteorological data. To this period correspond, in addition to the creation of national meteorological societies, the organisation of meteorological services between 1855 and 1890, the publication of daily bulletins and the foundation, in 1873, of the International Meteorological Organisation. The analysis compared of the articles of François Arago %u201CSouth the prédiction du temps%u201D (1858) and de León Teisserenc of Bort %u201CSouth the prévision du temps%u201D (1886) illustrates on the progresses of the predictive meteorology and the climatology sinóptica in this second half of the 19th century; while the first impossible esteem predict the time with twenty-four hours of antelación, the second, rebosante of hope, proclaims the splendid future of the meteorological prediction to measure that improve the instruments of observation and the knowledge of the atmospheric dynamics. Between a big number of contributions of the greater interest, stand out the maps of clouds of Fitzroy, the diagram of ciclón extratropical elaborated by Ralph Abercromby (1896) and the installation, this same year, under the direction of Teisserenc of Bort, of the Observatory of Dynamic Meteorology of Trappes; before, in 1882, they Go Bebber had recognised the usual paths of penetration of the currents disturbed in Europe. The first third of the centuria current, by what does to the meteorological prediction, offers like facts particularly notable the description and representation of the ciclón extratropical of frontal structure or Norwegian by Jacob Bjerknes (1919), the coining of the ahead Polar concept by the own Jacob and Halvor Solberg (1920) and the classification of masses of air by Tor Bergeron (1928). It is to notice that the contribution of the School of Bergen will constitute the basic foundation of the predictive meteorology until our days. To this first third of century corresponds also the invention and practice of the first radiosondeo by the French Bureau (1929). To the development of the aviation aroused by the II World-wide War owes the detection of the currents in chorro temperate; finalised already the conflict, would produce the discoveries of the jet subtropical and, afterwards, of the equatorial. It is not precise to put up the price of the importance that revisten for the meteorological prediction the images of satellite from the put in orbit of the Shots I (1960) and, especially, of the SMS-GOES (1974), first of the satellites geoestacionarios, that, in successive generations, constitute the basic pieces of the Program of World-wide Meteorological surveillance; one of which is, precisely, the METEOSAT. We add likewise, between the instrumental of observation more sophisticated, the employment of radars Doppler. They are diverse the programs that develops the World-wide Meteorological Organisation in addition to the already quoted of World-wide Meteorological surveillance, as for example, on the ciclones tropical and the hypothesis of climatic change. We mention also the singular importance of the International Symposium on %u201CThe life cycles of extratropical cyclones%u201D (1994), summoned by the University of Bergen to commemorate the LXXV Anniversary of the description of the ciclón extratropical or Norwegian by Jacob Bjerknes. It constitutes the description of this and of his fronts associated the big contribution of the Norwegian School to the contemporary meteorology, while descarta the ahead Polar existence conceived by her.
The meteorological prediction account today with powerful computer systems that process registers of multiple atmospheric stations in earth, data aerológicos, images of satellite and radar for, with employment of programs increasingly sophisticated, offer prognoses to short (12-24 h.) And half term (until three days). In Spain, the National Institute of Meteorology handles, like basic tools: the model of numerical prediction HIRLAM-INM that offers prognoses, four times to the day, with a space resolution of 17 * 40 kilometres; products of other numerical models foreigners and of the European Centre of Prediction to Half Term, as well as distinct technicians of statistical predictions. I complement for the prediction to very short term are the data supplied by the network of 14 meteorological radars, of type Doppler, the network of detection of rays, the images in high resolution of meteorological satellites and the network of automatic and conventional stations. Basic pieces are the Groups of Prediction and Surveillance (G.P.V.), situated in The Coruña, Santander, Valladolid, Saragossa, Barcelona, Valencia, Madrid, Seville, Málaga, Palma de Mallorca, and Las Palmas de Gran Canaria, that elaborate prognoses in his field of influence, base for the state prediction that provides the National Centre of Prediction.
PRESION ATMOSPHERIC: Weight of the existent atmospheric column on the place of observation. The one who exerts on each one of us equivale to some 17,5 Tm., roughly the weight of a cube of lead of 1,20 m. Of edge
RADIACION ELECTROMAGNETIC: compound Energy by a spectrum of electromagnetic waves of wide range of lengths that propagates to 300.000 km/s. Through the empty and in a straight line.
The electromagnetic radiation is organised in spectral bands of distinct wavelengths and frequency, is the designated complete electromagnetic spectrum or %u201Crainbow of Maxwell%u201D, that covers from the very short lengths (gamma rays and X-rays) to the long of the waves of television and radio
SOLAR RADIATION: The Sun is a sphere of gas incandescente situated to a half distance of the Earth of 150 million kilometres and with a temperature in surface of 5.800º K (5.527º C). The heat issued by the Sun is the main source of energy that receives the terrestrial atmosphere; this irradiates continuously splits of his mass to the space in shape of electromagnetic energy and of particles to big speed. The enormous radiant energy of the Sun has his origin in the nuclear reactions that transform cores of hydrogen in helium, in favour of the high temperature and strong pressure. In these conditions gives off an enormous quantity of energy.
RADIOSONDEO: The characterisation of the atmospheric time, to effects of predict meteorological, precise of the knowledge of the existent conditions in surface and in the upper layers of the atmosphere. A radiosonda is a small meteorological station (meteorógrafo) launched to the atmosphere by means of a captive globe and instrumented with a team of transmission that sends data of temperature, pressure and humidity. The meteorógrafo with the sensors of the three distinguished elements is shut in a capsule, that protects of the humidity and of the radiation, at the same time that pipes a current of air to ventilate them. A mechanism giratorio links successively the instruments with the emisora, that transmits the signals to the meteorological station in earth. During his promotion the transmitter sends signals of radius with the modifications that go experiencing the climatic elements in the diverse levels. The thread of suspension serves of antenna. The radiosondas arrive to reach big altitudes before that the globe of neopreno or polietileno burst and descend to earth in parachute. The recent employment of Systems of Global Position (GPS) has allowed to measure with big accuracy the position and speed of the radiosondas. With the data of the radiosondeos elaborates the diagram of radiosondas that describes the course of the temperature, pressure and humidity of the air to different altitudes. Likewise, the data processed transmit to the headquarters of the national meteorological services for the preparation of the letters sinópticas.
READJUSTMENT ENERGETICO PLANETARY, PROCESSES OF: The different distribution of the planetary energetic balance in the distinct bands or bands of latitude does necessary the development of mechanisms of energetic readjustment that favour the maintenance of said balance. It exists an accused meridian gradient of temperature between equatorial and polar latitudes caused by the alterations that registers the energetic balance because of the own latitude, incidence of the cloudiness, the relief, the albedo, the length of the day and the presence of oceanic masses. If the energetic system earth-atmosphere did not have processes of horizontal transfer of heat, the temperature would diminish progressively in the polar latitudes and would increase in the next to the equator, phenomenon that does not give off of the reading of registers intrumentales. The mechanisms of transport of energy that help to reestablecer the planetary energetic balance designate %u201Cprocesses of horizontal or meridian transfer%u201D and take place, constantly, in the own breast of the latitudes intertropicales and of the half and high latitudes, and between both climatic fields.
The transport of heat to the poles realises by means of the atmosphere and the oceans, corresponding to the atmospheric circulation 80% of the transfers of heat to upper latitudes and the rest to the marine currents. The horizontal transport takes place in shape of latent heat and sensitive heat, and varies in intensity according to the latitude and period of the year. The coefficient of maximum transfer corresponds to the faja situated between the 35º N and 45º S.
The horizontal transport of latent heat produces , almost in his whole, in the two or three first kilometres of the troposphere, and is consequence of the existence of the hemispherical belts of winds in the big zone of west general circulation. By his part, the transmission of sensitive heat in meridian sense is motivated by the trip of the masses of air and has two maxima, in surface and in 200 hPa. The transport of heat in altitude is particularly important in the zone subtropical (cell of Hadley), whereas the greater percentage of the heat transported in surface, in shape of sensitive heat, is linked to the movement of the ciclones extratropicales. The intensity of the flow of energy transferred to the poles is in function of the meridian gradient of temperature; in winter, this gradient is maximum, and, in relation with them, the processes of energetic transfer in each hemisphere. They are two, basically, the mechanisms of the atmospheric circulation that participate in the horizontal exchange or meridian of energy calorífica between distinct planetary latitudes. In the field intertropical the cell of Hadley is the attendant to distribute the excedente calorífico equatorial to latitudes subtropicales. This process includes: absorption of heat by the winds alisios of surface that circulate to the zone intertropical of convergence; promotion and release of heat by condensation in the band nubosa equatorial; cooling radiativo in the peak of said band nubosa; divergence in the high layers on equinoctial latitudes and subsidencia, to latitudes subtropicales, in the band of high pressures. By his side, in half and high latitudes, the diet of waves of Rossby allows the trip of masses to distinct latitudes to his homes or sources. In effect, the circulations of high index, with currents in chorro to upper speeds to 150 km/h, do not favour the energetic exchanges between latitudes subtropicales and polar, causing increase of the meridian gradient of temperature between both sectors. In these cases, the atmosphere reaches a critical point and precise readjustment calorífico; this achieves in the circulations of low index, characterised by the existence of currents in chorro to lower speed and apparition of ondulaciones in the west circulations, that, of zonal, becomes meridian, with presence of dorsal of blockade and planetary valleys. The first displace masses of air subtropical to upper latitudes and, at the same time, the vaguadas movilizan masses of cold air (polar and arctic) to the tropics. It achieves , like this, diminish the meridian gradients of temperature and reestablish, momentáneamente, the planetary energetic balance.
RELENTE: The term relente, derived of the Latin verb relentesco (entibiarse, cool), alludes to the precipitation of gotillas of ínfimo size, fruit of the condensation originated by nocturnal cooling in situations of atmospheric calm and skies cleared, that produces without training of clouds. Of the Latin word serenum (cleared, without clouds) derives the sober denomination for the relente that falls from midnight when dawning.
CLIMATIC RISKS: The climatic risk is the plasmación territorial of a human performance that neglects the existence of some extraordinary meteorological phenomena, own of the climatic shots of a geographic field. It is used to to establish an improper synonymity between the concepts of "risk" and "catastrophe"; the first becomes of the second. The "catastrophe" is an extraordinary natural fact that supposes grave damages for the economic activities of a society and, even, human losses. An upper degree in the assessment of the catastrophe would be the "disaster" that comes defined like the serious interruption of the functions of a society that causes human losses, material or environmental extensive that exceed the capacity of the society affected for resurgir, using only his own resources. The "risk"
It is the contingency of a damage caused by a human performance little in accordance with his half natural. The natural episodes of extraordinary type are evento that form part of the physical characters of the geographic spaces affected. They are therefore "extreme phenomena" that purchase category of "risk" when the man modifies for his provecho the half natural in where it manages his work altering, like this, the derivative effects of the development of these natural episodes. The natural risk is, then , product of two factors of índole human, the threat and the vulnerability and his elder or lower degree comes given by the calculation of losses occurred in a determinate region during a period of reference for a danger given.
ROCIO: Condensation in virtue of the principle of the cold wall on surfaces that, cooled by nocturnal irradiation in situations of atmospheric calm and skies cleared, experience a descent of sufficient temperature so that the air in contact with them reach the point of rocío. In vegetal trainings, the steam of water that changes of state can proceed of the own transpiration of the plants.
ROSA NAUTICAL: Object of artistic designs in the portulanos, other historical cartography of the Mediterranean Western and until in the primitive brújulas, the rose naútica is known also like rose of the winds, for indicating the courses of the eight main, to know: tramontana (N), gregale or Greek (NE), raise (And), sirocco or jaloque (), midday, áfrico or austro (S), lebeche or garbino (SW), poniente (W) and maestral, teacher, mestral or mistral (NW). In the Algerian coasts knows like carpenter mallorqín to the north hard wind that azota this pertinent space of Balearic.
ROTACION TERRESTRIAL: Although Aristarco of Samos, in the 2nd century to.J.C., it equated the Earth to a ball that gave gone back on himself same , the idea that it was flat and around her turned daily the sun and the remaining stars perduró until the big geographic discoveries. Previously diverse Greek authors had signalled that the Earth was a sphere. Like this, Pitágoras and his disciples defended (s. VI-S.IV To J.C.) The esfericidad of the Earth; Aristotle, in the s.iv to J.C., in his work Of Caelo, aimed, like proof of the spherical form of the Earth, that %u201Cif the Earth was not spherical the eclipses of Moon would not exhibit the sections that know them %u201D. Estrabón, by his part, signalled, in the s. I to.J.C., that %u201Cthe curvature of the unseen sea to the navegantes the most distant lights that are to level of his sight%u201D. The circunnavegación of Juan Sebastián Elcano evidenció the redondez of the earth, but no his rotation. A demonstration palmaria of this did not produce until 1851, thanks to the famous experiment of the pendulum of Foucault, that did patent the existence of the absolute eddy and, with her, of the terrestrial rotation. This consists in the complete twist of the Earth around his polar axis in a day sidéreo, whose length, of 86.164 seconds, results 3 minutes and 56 inferior seconds to the one of a half solar day. Although Gustave Coriolis had formulated his famous theorem in 1843 and Leon Foucault realised said experiment in 1851, would pass still a century until it generalised the recognition of the leadership of the terrestrial rotation in the general atmospheric circulation. It is true that do not are missing precedents, especially the one of Ferrel, that attributed, in 1856, by force of Coriolis the incurvación of the alisio westward; but, in all his amplitude, the incidence of the terrestrial rotation in that, with assessment, no exenta of controversy, of a series of a series of inherent principles to that (conservation of the absolute eddy, conservation of the moment of rotation of the absolute eddy, conservation of the moment of rotation around the axis of the poles), will not produce but in the second half of the century twenty. It suffice to repair in the years of publications of Pierrre Pédelaborde, so significant in said sense, as %u201CHim tourbillon%u201D (1958) and %u201CThem données of the climatologie%u201D (1966).
METEOROLOGICAL SATELLITES: The launching, on 1 April 1960, of the satellite SHOTS-1 inaugurated the extensive relation of satellites of meteorological purpose that have contributed to the improvement of the atmospheric prediction and to the improvement of the knowledge of the times and world-wide climates. In spite of some previous attempts (Vanguard 2, Explorer 6 and 7), the SHOTS-1 was the first entirely conceived satellite by the NASA for the observation of the atmospheric time. It began like this the space career of the meteorological satellites that would have continuity in the following years, by his lower cost of launching, with a series of units of polar orbit managed by the American administration and, afterwards, by Soviet (Meteor), Russian (Meteor) and Chinese (Feng-Yun). A crucial fact for the programs of remote observation of the atmosphere was the approval by the World-wide Meteorological Organisation of the Program of World-wide Meteorological Surveillance, in 1963, inside the cual the meteorological observation from meteorological satellites constitutes a basic piece. The uninterruptible surveillance of the atmospheric time demanded, however, a different type of satellite, whose orbital speed was exactly synchronised with the rotation of the Earth, so that it could keep constantly in the vertical of a determinate point of the terrestrial surface. This condition achieved with the construction and put in orbit of the satellites of orbit geoestacionaria. The first satellites with this orbit were launched in 1966 and 1967 (series ATS, Applications Technollogy Satellite) and provided the technological bases for the set up of the series SMS (1974 and 1975) and GOES (Geoestationay Operational Environmental Satellite), whose first prototype was launched on 17 May 1974. In 1978 two new satellites geoestacionarios would put in orbit: the first, the satellite GMS japones, known with the significant name of %u201CHimawari%u201D or %u201CTornasol%u201D, in July of 1977; the second, on 23 November 1977, the METEOSAT, managed by the European Agency of Space (THIS). To them they would follow the satellites geoestacionarios of the Soviet Union (GOMS), India and the most recent of Russia (Elektro) and China (FY-2).
By his orbit distinguish : to) satellites geoestacionarios, that situate in orbit on the Ecuador (0º latitude) to distance of 35.800 Km., out of the atmosphere, in the designated "ring of Clark"; to said altitude results, practically, despicable the terrestrial gravitational attraction. These satellites possess a movement of uniform rotation around his main axis, oriented simultaneously to the of rotation of the Earth; of this way, complete his orbit in 24 hours, what allows them remain on the same point of the equator (from here his denomination, geo-estacionarios or geosíncronos). Therefore, the angular speed of rotation of the satellite coincides with the one of the Earth, that is to say, 360º/24 h., and his sense of rotation, as the one of the Earth, is of west to east. In consequence, the meteorological satellites geoestacionarios supply images of a same planetary area, when finding always on the same point regarding the Earth. This fact allows that the satellites geoestacionarios attract and remit a lot of images of the area that cover, that is to say, that have a high temporary resolution. By against, given his orbital distance, the space resolution is forzosamente low and worsens satisfied moves away of the nadir, or point subsatélite in the Ecuador. A disadvantage of these satellites is that they observe the earth like a disk and to the edges this vision results very oblicua, losing a lot of detail in upper latitudes to the 50º N and S; and b) satellites of polar orbit and helium-synchronous, that have an orbital distance a lot of minor, from here that they were the first in orbit to beginnings of the years sixty, by technical reasons and because of the lower costs of launching. They situate to an altitude between 800-900 Km. Of the Earth and the calificativo of "polar" comes given because the satellite turns in an orbital plane that contains the poles north and south. Some of them are, besides, "helium-synchronous", owing to that his orbital plane follows the apparent movement of Sol, by what visit all the points of a same parallel to a similar solar hour, without mattering the stations of the year. His orbital period, that is to say, the time employed in giving a hard complete orbit, roughly, 100 minutes. The satellites of polar orbit have big space resolution by the lower distance of his orbit with regard to the terrestrial surface.
In the actuality, the network of world-wide meteorological surveillance is integrated by the following units (vineyard. Figure): to)satellites of orbit geoestacionaria: Meteosat 6 and 7 (EUMETSAT), GOES-And (8 and 10), GOES-W (9) (United States), GMS-5 (Japan), Insat II-B (India), GOMS-N1 %u201CElektro%u201D (Russia) and FY-2 (Rep. Popular China); b) of polar orbit: NOAA 12 and 14 (United States), Meteor 2-21 and 3-5 (Russia) and FY-1C (Rep. Popular China). And beside them the series of satellites of meteorological purpose included in the military program of the exercise American (satellites DMSP).
They exist other satellites whose information results valuable for the atmospheric studies; between them, the ones of the series NIMBUS, initiated in 1964 and that, from the NIMBUS 7 (1978), transport the radiometers CZCS (Coastal Zone Colour Scaner), designed for the study of the surface of the sea and a spectrometer for the measurement of the layer of ozone and the TOMS (Total Ozone Mapping Spectrometer). Big importance revisten likewise the satellites of climatic purpose ERBS (1984), instrumented with able radiometers to evaluate the balance of radiation and the quantity of aerosols and present gases in the stratosphere and TOPEX/POSEIDON (1992) American with the aim of the oceanic exploration, among others included in the program multiestatal %u201CMission of the Earth%u201D
The products facilitated by a meteorological satellite present in magnetic support (strips or diskettes with digital information) or on paper (photographic product). The meteorological satellites carry installed radiometers that act in the visible and infrared wavelengths of the electromagnetic spectrum. The satellites geoestacionarios operative in the actuality receive information of 3 bands of electromagnetic radiation (visible, infrared half and infrared thermal), whereas the meteorological satellites of polar orbit are used to to handle 5 bands or channels of radiation (two channels in the visible, two in the infrared thermal and one in the infrared near). Each one of them with different possibilities for the climatic investigation. In the visible images (0,5-0,9 um in the electromagnetic spectrum) what appears white or clear has this tone in the reality, being, therefore, clouds, fogs, surfaces snowfalls or sectors desérticos very clear. His problem is that they offer only information during the day, since during the night result totally dark. The infrared images (between 10,5 and 12,5 um or infrared thermal) are thermal maps or of contrasts of temperature of the bodies observed. In them the dark tones correspond to hot surfaces and the clear tones to cold surfaces. They are images particularly ideal to detect levels nubosos, since they attract perfectly the thermal differences that correspond to distinct altitudes, resulting very appropriate for the study of clouds convectivas. Finally, the images of the infrared half, known like images of %u201Csteam of%u201D water (5,7 to 7,1 um) put that this spectral band sees strongly absorbed by the steam of water, are representative of the humidity in the layer troposférica comprised between 500 and 300 hPa.
The current units of satellite geoestacionario METEOSAT-5 and GMS-5 allow to obtain new products of big interest for the climatic studies, between them images of high resolution with indication of direction of wind in surface by means of the treatment of infrared original images and visible (High Resolution Visible Wind product).
The proportionate images by the meteorological satellites are dynamic %u201Dsources%u201D of the climatology and meteorology, given the immediacy of his disposal for the researcher of the time and climate. The meteorological satellites of next generation will improve the space and temporary resolution, including new channels of information that will contribute to the improvement of the atmospheric studies. The future of the programs of meteorological satellites offers in the picture attach.
DROUGHT: Absence or shortage of rains in a period of prolonged time (of the lat. siccus, dry, arid, without rain) that causes dehydration in floor and vegetal species. The drought supposes an alteration of the normal rhythm of those, by atmospheric causes, and the magnitude of his effects associates to the degree of human occupation, agricultural transformation, urban development and efficiency of the hydraulic planning of the area affected. They are used to to handle drought and aridez like analogous expressions, when the first alludes to a temporary state caused by mechanisms of atmospheric circulation and the second is condition condigna, by condicionamientos geographic, to the climatic conditions of a region.
SHEAR-LINE: Line of cizalladura that originates in the flow of the alisios, causing sometimes intense showers. The shear-line is a discontinuidad that results of the superficial convergence that cause winds with opposite directions and speeds more or less contrasted.
SOLANA: Slope oriented south in temperate latitudes and subtropicales of the northern hemisphere and north in the austral. Regarding insolación, adret contrapone to umbría, since, to equality of other conditions, aventaja to this in hours of sun and quantity of solar radiation received by unit of surface.
SUBSIDENCIA SUBTROPICAL: The convergence between coladas polar and pertinent air of low latitudes, that knows likewise a process of confluencia internal when penetrating parallel of radio every time lower (r = R * cos to), translates in a phenomenon of subsidencia very active to latitudes subtropicales. Said movement deprives widely on the horizontal circulation, to whose scarce entity allude the denominations of Pferdebreiten and horse latitudes, allusive to that from the sailboats, inmovilizados in the breast of these calms, launched by embroiders it the horses to save freshwater provisions. The subsidencia originates skies cleared, drought and increase of pressure. Result of the subsidencia is the configuration of the maxima subtropicales (anticyclones of the Azores, California, Audible and Hawai, in the hemisphere north; Santa Elena, Sureste of Pacífico or of Pascua and south of the Indicate, in the meridional), that constitute authentic master pieces, like centres of dynamic and permanent action or cuasipermanentes, of the atmospheric circulation general, since by his condition of homes of masses of maritime tropical air, of his façades to less latitude split the alisios and the opposite encourage the circulation of the westerlies.
It ARISES-LINE: Discontinuidad of character cinématico, that originates bad time and precipitations in latitudes intertropicales. The French denomination of this perturbation alludes to the mechanism generator of the same ("poussées", push), since one arises-line develops when it takes place contrast of speed in the winds alisios with increase of speed in the back flow; this fact encourages a process of superficial convergence and promotion of air, with origin of clouds of vertical development, of elder or lower entity in virtue of the entity of the thermal investment of the alisio.
TEMPERATURE: physical Magnitude, referred to the thermometric scale of election, that expresses, the objective and sensitive degree of heat or cold existent in the atmosphere. Like this, then , it treats of a data obtained of objective way, thanks to the employment of a thermometer or radiometer, measurers that do not explain the latent energy until it frees and translate in heat. Different notion to the temperature, usually handled in climatology and meteorology, is the one of sensitive temperature, of big interest for the climatology and medical meteorology, whose measurer is not the thermometer neither the radiometer, but the own human body. In consequence, does not treat of an objective data , but subjective, closely related with the idea of confort thermal, dependent jointly of temperature, relative humidity and wind. It suffice to signal, like example, that, with wind of 50 km/h., a temperature of 2º C is suffered by the human organism like equivalent to %u201315º C.
STORM OF WIND: atmospheric Situation characterised by the blow of winds to big speed. They consider tempestuosas the speeds that rebasan the strength 10 in the scale of Beaufort or the 85 Km/h. The storms of wind link to diverse atmospheric situations.
TIME: it Constitutes the demonstration of the state of the atmosphere, that the man perceives and remembers. In opinion of the climatólogo French Pédelaborde the atmospheric time would be %u201Cthe perceived and lived by the man%u201D whose causes deserve precise explanation.
TYPE OF TIME: Pattern of atmospheric behaviour that, in function of his frequency of apparition, characterises the shots of the climate of a region. The type of time is the object of main study of the climatology sinóptica, that describes the shots of the climate of a region from the analysis of the masses of air and the types of time derived of his trips.
EDDY, LAWS OF THE: Although Aristarco of Samos in the 2nd century aJ.C. It compared to our planet with a ball that gave gone back on himself same, during centuries thought that the Earth was flat and that, each day, turned around her the sun and the other stars. The systematisation of the new ideas about the movements of the Earth, in particular of traslación, contained in Of revolutionibus orbium coelestium (1543) of Copernicus tripped with serious difficulties to open way, and good sample of this is the forced abjuration, in 1632, of Galileo Galilei.
The experiment that evidenció the terrestrial rotation is very late; theoretically, with the discoveries of Newton could have posed, but in the practice resulted impossible. It would not be but in 1851 when the French physicist Leon Foucault, from the physical law of the invariabilidad of the plane of swing of the pendulum, put of self-evident the existence of the absolute eddy and, with him, of the terrestrial rotation. However, although Gustave Gaspard Coriolis had formulated his famous theorem of 1843 and Foucault realised the aforementioned experiment eight years afterwards, had to pass still a century so that some tratadistas initiated the assessment of the incidence in the atmospheric circulation general of several principles linked to the terrestrial rotation; it treats of the principles of conservation of the absolute eddy, moment of rotation of the absolute eddy and conservation of the moment of rotation around the axis of the poles.
The absolute eddy is the twist of a body or of the own terrestrial surface around the vertical; his speed comes given by the formula w * sen to , being w the angular speed of the Earth and to the latitude of the point considered. To tenor of said expression, the speed of the absolute eddy, coincident with the angular of the Earth, results maximum in the poles, and invalid in the equator. By convention, indicates with positive sign the eddy of contrary twist to the manecillas of the clock, that is the one of the hemisphere north, and assigns the negative to the in accordance with them, imperante in the hemisphere south.
The designated laws of the eddy govern the atmospheric circulation in high and half latitudes, while it would deprive the principle of conservation of the moment of rotation around the axis of the poles in the field intertropical. In the zone of west general circulation, the atmospheric columns that save his dimensions, keep, in virtue of the principle of inertia, the speed of the eddy purchased in his home. Thus, a flow that lose latitude, integrated by atmospheric columns in said conditions, since these possess concerning the surface a cyclonic relative eddy, the flow in question purchases a cyclonic general curvature, incurvándose eastwards; course that also would follow a flow that, composed by columns of the expressed characteristic, won latitude, receiving anticyclonic curvature. In sum, the principle of conservation of the absolute eddy would determine the preponderancia of the west general circulation in high and half latitudes.
Different situation poses with modification in the dimensions of the columns; although these, by the own effect of the gravity, keep the perpendicularidad to the terrestrial surface and the symmetry of twist around his axis, with uniform movement, so that it results of application the moment of rotation (v * r =v´ * r´). To tenor of this, the column that increases his radio of twist, reduces parallel and proportionally the speed of this, and vice versa. It justifies like this the apparent contradiction that supposes the anticyclonic rotation of masses of air that lose latitude. The hydrodynamic effect of the obstacle, with his succession of anticyclonic and cyclonic curvature, constitutes a specific demonstration of the principle of conservation of the moment of rotation of the absolute eddy.
Unlike the angular speed, identical for all the points of the planet, the linear varies with the latitude, is maximum in the equator (465 m/s) and invalid in the poles. Likewise it has to consider that the gaseous mass that constitutes the atmosphere lacks the consistency and rigidity of a solid surface; and, in consequence, the contrasts latitudinales of speed propician the fragmentation and the meridian trips. The movement of terrestrial rotation around the axis of the poles obeys likewise at the beginning of conservation of the moment of rotation; in virtue of same, the flow that, in the field of force of the principle of conservation of the moment of rotation around the axis of the poles, loses latitude, increases his radio of twist, when penetrating parallel of greater diameter, reducing, therefore, his linear speed, and remaining delayed concerning the rotation W®And. The evolution results reverse for the flow that wins latitude and reaches circles of radio every time lower (r = R * cos to), increasing, in consequence, his linear speed of rotation, that, when exceeding, the one of the point of arrival, motivates a west current, in the sense of the terrestrial rotation. Some tratadistas find in this mechanism the justification of the east flow, that deprives, to the different levels, in the field intertropical.
STORM OF HAIL: The storms of hail are meteorological episodes characterised by the solid precipitation and characterised by his local character or, still, punctual, frequency of apparition estival and damages in the agricultural activity when coinciding with the period of development of frutales, cereals and hortalizas.
TORNADO: The word tornado, pertinent of the Spanish verb tornar, turn, alludes to the meteorological phenomenon characterised by the enormous speed of twist of the wind that produces in the funnel or trompa that descends from a cloud convectiva. If the phenomenon produces in marine surfaces receives the denomination of tromba, trompa, bomb or sleeve.
The wind reaches speeds almost impossible to measure by the anemometers (between 160 and 450 km/h). The diameter of the funnel has a hundred of metres but the horizontal gradient of pressure is brutal. It is frequent that the contrast in a so small radius result of 25 or 30 mb, but in occasions the descent of pressure can rebasar 100-150 and even 200 mb. The tornados are atmospheric phenomena that unchain , mainly, in half latitudes. The origin of the tornados links to the training of %u201Ca supercélula%u201D, that is to say, a cloud of storm of big magnitude and violence developed in some surroundings hidrostáticamente unstable. His training demands continuous contribution of warm and humid air in the low levels, that comes encouraged by the development of a current in chorro of low levels, apparition of high vorticidad thermal in the atmospheric column by presence of a vaguada in altitude, in occasions accompanied of a current in chorro or ramales of the same and apparition of a strong persistent eddy that, from a central point, transmits to the whole of the storm. In the interior of the supercélulas formed in these conditions of atmospheric unsteadiness originates a mesociclón, that is to say, a region of 1,5 to 5 kilometres of radio that, from 5.000 metres of altitude, begins to turn ciclónicamente to the base of the cloud with a speed of 65 km/h. In the edge southwest of the mesociclón form funnels of very fast speed of rotation that reach the floor and drags all what find in his route.
UNITS OF MEASURE: To measure each one of the climatic elements exist the corresponding units. Like this, before it concluded the 18th century had been elaborated the thermometric scales more spread, that is to say, the ones of Celsius, Fahrenheit, centígrada and Reamur. The usual synonymity of scale Celsius or centígrada, that assimilates both, is improcedente and erroneous. One and another handle like fixed points the ones of fusion of the ice and ebullición of the water, and have the interval between both divided in one hundred equal parts or degrees, but with the difference that the scale Celsius attributes 100º to the first of said fixed points and 0º to the second, while the most widespread scale, that is to say, the centígrada, contrived in 1743 by Pierre Christin, and of coincident way and practically simultaneous by Carl von Linné, does it to the reverse, or was, 0º for the melting-point of the ice and 100º for the one of ebullición of the water. Wide implantation in the Anglo-Saxon field possesses the scale owed to the prusiano Gabriel Daniel Fahrenheit, where the fixed points indicated correspond, respectively, to 32º and 212º F, mediating between both 180º F. The 0º F equivale to %u201317,8º C, while the 100º C, that his creator pretended that they coincided with the temperature of the human body, exceed the one of this and go up to 37,7º C. Scale fallen into disuse is the proposal by Reaumur that numbers the expressed fixed points with 0º and 80º R. Finally, during , during the 19th century, to avoid negative values in thermodynamic investigations and thermometric observations proposed the absolute scales of Kelvin and Rankine, designated like this because his 0º is the absolute zero, temperature to which the bodies have lost all rest of heat; the scale Kelvin results to add 273,15º, briefly 273º, to the scale centígrada, and the Rankine to add 459,6º to the Fahrenheit. The 0º K equivale to %u2013273º C and the 0º Rank to %u2013459,6º F.
Regarding the content of steam of water in the air, basic concepts are the ones of absolute humidity, the relation or proportion of mix, specific humidity, tension or pressure of steam and relative humidity. The absolute humidity expresses the weight, in grams or submúltiplos of east, by m3 of air. It treats , nevertheless, of a problematic data, by what the air is comprimible and his variable density, so that 1 m3 of air can suppose masses very different. For obviar this problem, coined the concepts of relation or proportion of mix and specific humidity, where the weights of the steam of water refer , respectively, to the Kg. Of dry air, or simply, to the Kg. Of air, without embezzling the steam of water. By his part, the tension of steam indicates the pressure that would exert this isolated of the rest of the atmospheric mass, and does it in millimetres of normal mercury ( mm. Hg), milibares (mb.) Or hectopascales (hPa). Finally, the relative humidity, degree higrométrico of the air or fraction of saturation expresses in so much by one and, usually, in percentage.
The traditional scale to refer to the total cloudiness was of eleven degrees, so that it did correspond 0 with the sky cleared and 10 with the entirely covered. At present, to avoid two digits, uses a scale of nueve degrees: 0 it identifies to the clean sky, raso or tended and the remaining portions, octas or eighth, to the part of the celestial vault cover of clouds, until a maximum of 8 for the sky covered or marquee.
To measure the precipitations, considers that all are melted and does abstraction of the evaporation, infiltration and escorrentía. The precipitation indicates in mm. Of height or l/m2, equivalent expressions. The intensity of the precipitation measures in mm./Minute or calculates in mm./Hour.
Until dates relatively recent the atmospheric pressure measured in millimetres, centimetres or inches. The inconvenience of the data did not consist only in expressing a strength by unit of surface by means of length, that is to say, did not treat of a mere formal mistake; the essential problem rooted in that a column of mercury of equal height and identical volume can mean a strength and, therefore, a diverse pressure, in function of the variables of density of the mercury, supeditada to the temperature, and of the acceleration of the gravity, distinct in different points of the planet. For obviar this difficulty, the International Barometric Agreement defined the called millimetre of normal mercury, mm. Hg The Torr, employed like references the density of the mercury to 0º (13,59 gr./Cm3) and an acceleration of the gravity of 980,665 cm/s2. Like this, then , the pressure considered normal is of 760 mm. Hg. But the atmospheric pressure what also with other units of measure, such as the Piece (Pz) in the system MTS, the physical atmosphere (atm.), the Kilopond or Kg. It forces/cm2 and, especially, the milibar (mb.) And the hectopascal (hPa.). The unit of pressure in the system cegesimal is the baria (dina/cm2), but, in his place, for resulting too small, employs the milibar (mb), that equivale to 1.000 barias (1.000 dinas/cm2). The normal pressure results of 1.013 mb., so that the milibar corresponds, roughly, to &tailcoat34; of the mm. Hg Or Torr. Increasing diffusion possesses the hectopascal (hPa), multiple of Pascal (Newton/m2), that is the unit of pressure in the system Giorgi or MKS, although, by reasons likewise of functionality, uses that, that is to say, the hPa., equivalent to the milibar.
Therefore, the normal atmospheric pressure to level of sea answers to the following equalities: 760 mm. Hg Or Torr = 1.013 mb = 1.013 hPa = 101,3 Pz = 1 atm = 1,033 Kiloponds or technical atmospheres.
The horizontal gradient of pressure calculates in unit of pressure (mm. Hg, mb, hPa,...)/Degree of meridian, segment of 60 marine miles or 111,1 Km. By his part, the barometric gradient of height comes given in metres/mm.hg, metres /mb. Or hPa.
Of the wind interest, especially, course and speed. The first indicates by means of the rose of the winds, sexagesimal degrees or centesimales from the N. And in the sense of twist of the manecillas of the clock, also by quadrants, being first the comprised between north and east and numbering the three remaining with the sense of aforementioned twist. Finally, the wind speed gives in m/s., Km/hour, terrestrial miles/hour and, with frequency, also in marine miles/hour or knots (Kn); the knot supposes 0,51 m/s or 1,852 Km/h.
WIND: Air in movement, owing to the contrasts of atmospheric pressure; his basic data are the ones of direction and speed or, for the marine, with reference to the scale of Beaufort or to any of his variants, strength. The speeds vary from the rayanas with the calm (5 km/h.) To the huracanadas that exceed the 115 km/h. , to reach the maxima turning, excepcionalmente, to more than 400 km/h. In the tornados.
WIND OF GRADIENT: Wind whose courses is parallel to the vector of gradient and perpendicular to the isobars. The wind of gradient tends to vaciar the maxima or anticyclones and to fill up the depressions or minima, destroying ones and others.
WIND GEOSTROFICO: free Wind of rozamiento, parallel to the isobars and perpendicular to the vector of gradient. The geostrophic wind roots in the free troposphere and, on the terrestrial surface, in the oceans, where the rozamiento results practically despicable. The presence of a geostrophic wind or cuasigeostrófico results of main importance for the perduración of the centres of action, since the parallelism or cuasiparalelismo of the wind to the isobars avoids his destruction.
WEST WINDS (WESTERLIES): they Are, beside the alisios, the winds of planetary scale. The zone of west general circulation extends , in each hemisphere, between the pole and the subsidencia subtropical. The westerlies, encouraged by the maxima subtropicales and until by the low subpolares, are primordialmente promoted and governed by the laws of the absolute eddy, in particular by the principle of conservation of the absolute eddy.
REGIONAL And LOCAL WINDS: The importance of the regional circulations and venues of the winds has been stood out from the antiquity. The regional and local winds print particular shots to the climatic conditions of a territory, converting, in occasions, in the climatic element more significant of the same. The relation of regional or local winds that blow, in favour of ones or other atmospheric conditions, in diverse parts of the planet, is amplisima in relation with condicionamientos geographic specific, the popular tradition has given name to the distinct winds, that has remained until the actuality.
Winds of thermal shots colds, are, among others, the buran or purge, wind extremely cold and violent pertinent of Siberia that affects south of Russia, dangerous by the abundant snowfalls that originates; the crivetz, that blows in the earths of the low Danubio pertinent of the interior of Russia; the koshava of the countries of the ancient Yugoslavia that it is a cold wind of the noreste, pertinent of Russia; in Germany, receives the name of steppendwind the cold wind of the noreste pertinent of the Russian steppes. The vardarac is a polar wind, very cold, that blows in winter on the north of the sea Egeo.
In the Chinese coasts, the north cold wind receives the name of leung. The narai is a cold wind that azota, in the wintry station, the pertinent Japanese archipelago of the polar regions of the Asian continent. The pampero is a cold wind that blows in Argentina and south pertinent Uruguay and southwest; his blow produces with the step of a cold front and goes accompanied of turbonadas, stormy cloudbursts and brusque descent of temperatures; Buenos Aires receives, by half term, a dozen of pamperos to the year, generally, in spring and summer. In the altiplano Andean Peruvian receive the name of surazos the south cold winds that accompany of low temperatures and clean skies. With the name of sno designate the currents of cold air that blow in the Norwegian valleys, in winter, pertinent of the high earth (highlands) and that reach high speed in the fiords.
Local winds very warm is the chergui that affects to pertinent Morocco of the desert of the Sahara; wind sahariano is, likewise, the ghibli that blows in Tripoli. The kahmsim or chamsin is a warm wind, polvoriento and dry, of component south that blows, generally in spring, on Egypt and the Red sea; it produces in front of the depressions that displace eastwards through Africa northern or the Mediterranean suroriental. The shamal is a warm wind of the northwest that blows on Iraq and the Gulf Pérsico in summer. Similar characteristic presents the brickfielder or brickfelder that blows in the south of pertinent Australia of the deserts of the interior accompanied of storms of dust. The karaburan is an east violent wind or noreste that affects, in spring and summer, to the regions proximas to the desert of Gobi; the blow of this wind accompanies of eddies and storms of sand that hamper enormously the visibility, from here that, likewise, receive the denomination of "black storm". The audible is a warm wind that crosses pertinent Arizona of Mexico and California.
They do not are missing regional denominations or venues of winds associated to unstable atmospheric situations with development of storms. It is the case of the bayomo, strong wind and racheado generally linked with storms generated in the slope of windward of the mountain range of Master Saw in the south of the island of Cuba; of the churada, turbonada raging accompanied of rains that originates in the islands Marianas during the months of January, February and March; of the cordonazo, south violent wind that blows in the west of pertinent Mexico of the oriental sector of tropical storms situated in front of the coasts. The marin is a warm wind, of type sirocco, that accompanies of intense storms in the coastal areas of the Gulf de León in the south of France. The sudestada or suestado is a strong wind of the sureste that blows, in occasions, in winter along the coasts of Argentina, Uruguay and the south of Brazil and that causes sea bravía, accompanied of abundant cloudiness and rains. In the Gulf Pérsico the suhaili is the wind of the southwest that associates with cloudiness and precipitations.
In other cases, the apparition of a local wind links to the cessation of the rains, as it occurs with the wind elephant that blows in the coast Malabar, in the extreme southwest of the Indian, in September and October, signalling the end of the station of rains monzónicas and the start of the dry station.
They do not are missing, by his part, local denominations of the breezes; like this, in South Africa, the cool breezes receive the name of doctor and in Shangai of feh. In Hawaii, the breezes receive diverse denominations kapalilua, kohilo. In some agricultural regions of Japan know like matsukazee. In Portugal, the marinada receives the name of vento of baixo. The coromell is a nocturnal breeze that blows in the area of the Peace, south of the peninsula of Drop California, between November and May; it is this occasion, the thermal contrast establishes between some warm marine waters and a continental surface that, in this epic of the year, cools quickly during the night. In occasions the blow of the marine breeze approaches to the line of coast trainings of low clouds (strata). It is the case of the cacimbo blows of the southwest along the coast of Port Lobito, in Angola. It treats of a cool breeze that purchases this shot when circulating on the cold current of Benguela that circulates in front of the south western coasts of Africa. The name of cacimbo employs , likewise, to designate to the layer of fogs of irradiation-advección that gesta in this field by the presence of the mentioned cold marine current and that it is arrastada to the coast by the wind.
VOLCANOS And CLIMATE: Although volcanos and climate are distinct geographic realities without apparent relation a series of facts have gone manifesting the narrow connections that exist between both place that the violent demonstrations of the first saldan with alterations, of elder or lower entity, in the elements of the climate. The volcanic eruptions have allowed, besides, indagar the existence of mechanisms of circulation checked, subsequently, thanks to the improvement in the methods of atmospheric observation of altitude. The most signalled effects of the volcanic eruptions link with the modifications that impose the thermal registers, to scale hemispherical or global. The volcanic eruptions of explosive type cause variations in the planetary energetic balance because of the permanence, during several months, of ashes and volcanic gases in the low layers of the stratosphere. The volcanic dust creates a very fine veil that diminishes the atmospheric transparency, prevents the arrival of solar radiation to the terrestrial surface and generates optical phenomena between which project twilight effects, apparition of crowns, mists, suns and moons coloreadas. Budyko Has signalled that the alterations in the atmospheric transparency caused by the big volcanic eruptions are responsible of a cooling of 0,3º C between 1883 and 1984. If it is evident the thermal descent that, in the months or following years, cause the volcanic eruptions more forceful, less clear results the relation with the precipitations put that to the opinion generalised of a possible increase, other tratadistas have put of self-evident the relation, for the Iberian Peninsula, between important volcanic eruptions (Tambora, Agung, Chichon or Pinatubo) and development of dry periods. This shows the need to effect analysis individualizados of the volcanic eruptions and his effects in the elements of the to scale regional climate.
The paper desenpeñado by the volcanic eruptions in the variations of the terrestrial climatic system deserves diverse importance to the distinct authors, from which concede them a leadership stood out for the explanation of the climatic variability of the last centuries to which only attribute them, some incidence in the cooling of the back years to an important eruption. The incidence of the volcanic eruptions in the planetary thermal rhythm is one of the incógnitas of difficult answer in the current hypothesis of climatic change, when causing the contrary thermal effect to the of the accumulation of gases of effect invernadero in the troposphere.
ZONES OF CIRCULACION ATMOSFERICA: The two big zones of atmospheric circulation in each hemisphere correspond with the two flows of planetary rank, that is to say, westerlies and alisios, that characterise, respectively, the zone of west general circulation and band of the alisio; between both situate the high pressures subtropicales or latitudes of the horses (Pferdebreiten, horse latitudes). All the group finds subjected to the cosmic mechanism of the stations, that during the winter expands the first of the zones, to the detriment of the band of the alisio, with descent latitudinal of the maxima subtropicales; and to the reverse sucede in the corresponding summer. The isotherms show, to five kilometres of altitude, from latitudes subtropicales, a progressive reduction of values until the polar regions, with identical evolution of the atmospheric pressure average. Since in this field the absolute eddy possesses considerable speed, increasing to the pole, where result maximum and coincident with the angular of the Teirra, the wind circulates in sense W ® And , with arrangement to the law of Buys-Ballot, leaving the high pressures to his right. In this flow of the upper levels project, as authentic managerial systems, the currents in chorro or jet-streams polar and subtropical, that, linked to the terrestrial rotation, benefit , besides, of the transformation of thermal energy in kinetical. The preponderancia of the west flow in surface sees interfered and diminished by the distribution of earths and seas, that condition the fields of pressure, especially with the presence of extensive wintry thermal anticyclones, like the Canadian or the Siberian maximum. Permanent character, although reduced thickness, possess the high polar pressures, while it revisten semipermanente the drop subpolares, like the centre ciclonal of Iceland or the minimum of the Aleutianas in the hemisphere north and the areas depresionarias of the seas of Wedell and Ross in the austral. With difference, the most important perturbations, without that they are missing others of diverse origin, are the ciclones extratropicales or Norwegians, in whose origin exert paper of prime importance the currents in chorro. In the transcurso of the year the variation of height of the sun is important, marking with nitidez the thermal stations; of resaltar is likewise the game of masses of air térmicamente contrasted. Condition of master pieces of the atmospheric circulation general recognises to the maxima subtropicales, of raigambre primordialmente dynamic, linked to the active process of subsidencia subtropical, that revisten character of centres of permanent action or cuasipermanentes. They mark the divisional between the zone of west general circulation and the band of the alisio, constitute home of the maritime tropical air and of his opposite faces emanate, respectively, alisios and west winds of half latitudes. They include wide sectors of calm, from here the appellative of %u201Clatitudes of the horses%u201D; this phenomenon obeys to that the subsidencia deprives widely on the horizontal twist in anticyclonic structures with feeble horizontal gradient of pressure. On the other hand, the subsidencia imposes the skies cleared and the drought, giving origin to a belt, in one and another hemisphere, of deserts subtropicales. From the maxima subtropicales blow to the equator the alisios, literally maritime winds, since they lack continental sources (vineyard. Alisios).
Unlike the zone of west general circulation, in the band of the alisios, characterised by the thermal homogeneity, the stations difuminan until disappearing, and the references are, anyway, pluviométricas, especially where imperan the tropical climates, arriving to call %u201Chivernage%u201D in Africa Western and, as it indicates Humboldt, %u201Cwinter%u201D in the basin of the Orinoco, to the summer, the rainy station, while the Spaniards designated %u201Cveranillo%u201D to the winter, the dry station. More uniform, until approximating them pluviométricamente to the hipertropicales, is the distribution of precipitations in the called climates of the alisio. The presence of thermal investment in the vertical structure of this wind marks a clear difference between the oriental and western sectors of the oceanic zone where blow, with precipitations reduced in the first and abundant in the seconds, thanks to that the investment wins altitude and loses entity, until disappearing, with the loss of latitude, allowing powerful promotions of a warm air, very humid, provisto of extraordinary discharge of energy, fruit of a very active evaporation on warm seas and extremely unstable. To remember is likewise that, no of only and exclusive way, but yes paramount, is this field situate praises areas monzónicas; the combination of the monsoon of summer with the orographic factor provides some of the registers pluviométricos, around 12 m. Of annual average, higher of the planet, in observatories like the one of Tcherrapundji and Mawsynram in the mountains of Assam (NE of the Indian). Beside cinematic perturbations minors (Arise-line, Shear-line) appear others of more entity like the east waves and the ones of the west, and one, particularly violent, with a demonstration ingente of energy, terrible by his catastrophic sequelas, like the ciclones tropical. Precipitations estivales more regular and continuous offers the zone of convergence intertropical (Z.C.I.T.).
The approximation of the alisios of both hemispheres is distant to be homogenea, with nuances and variants that hardly can be reduced to diagram. In the band of low pressures intertropicales or equatorial, areas of calm (doldrums), with rains very abundant (pot-ou-noir), the alisios difuminan in these spaces of scarce horizontal circulation, dominated by powerful promotions of the air. Finally, the denomination ahead Intertropical or Front of the Monsoon applies to the contact of the alisio meridional that, transpuesto the equator and turned into wind of the southwest, goes in in contact with continental tropical air, very warm and dry; situations of this type would produce in relation with the minimum estival of the northwest of indicates it and the low pressures saharianas.
ZONE OF CONVERGENCE INTERTROPICAL: Band of meeting of the winds alisios of both hemispheres, of variable location along the year in relation with the intensity and trip latitudinal of the maxima subtropicales, origin of those.
CHURCH, C, BURGESS, D, DOSWELL, C. AND DAVIES-JONES, R. (edits.) (1993): The tornado: its structure, dynamics, prediction, and hazards, Geophysical Monograph 79, American Geophysical Union, Washington, D.C.. It USES, 637 pp.
GIL OLCINA, To. And OLCINA SINGINGS, J. (1998): Dictionary of climatology. Publishing accent. Madrid, 92 pp.
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