ATMOSPHERIC SCIENCE

Author: CALVO FERNÁNDEZ NATALIA.
Year: 2004.
University: COMPLUTENSE DE MADRID.
Place of defense: FACULTAD DE CIENCIAS FÍSICAS.
Place of preparation: FACULTAD DE CC FÍSICA.

Summary: The thesis presents a study of the impact of ENSO phenomenon both in the troposphere and in the middle atmosphere, and consists of two parts: The first part describes the ENSO signal in the tropics from satellite observations of temperature microwave in the second, we studied the spread of the ENSO signal outside the tropics, at mid-latitudes in the troposphere and high altitude in the middle atmosphere, using models and numeric data European Medium-Range Weather Forecasts (ECMWF). - The description of ENSO in the tropics has been done with the method of empirical orthogonal function (EOF) applied separately to the average zonal and the asymmetric component (the "Eddies", or waves) in the field of temperature MSU.De thus shows the signal contains components ENSO average zonal and termodinámicos.Así Accordingly, the zonal component corresponds to global warming by increasing tropical rainfall and cloud cover during the Rossby waves equatorial forzdas by convective heat anomalies in the far eastern Pacific. the analysis also concludes that the EOF ENSO signal is linearly independent of other processes such as the oscillation cuasi-bienial (QBO) and volcanic eruptions, which had not been demonstrated with such clarity previemente. - To study the ENSO signal outside the tropics, have utlizado two general circulation models (GCM), which was compaan with the latest rethought data atmósfericos ERA-40, ECMWF.El study is based composites , which contruyen taking the difference of the sets of events The Child La Niña occurred in the most intense period 1979-2000.De this way shows that both models in the data ERA-40, the signal was ENSO Spreads outside the tropics through waves Rossby.En the troposphere, these trains are known as wave patterns Pacífico-Norteamérica (PNA and PSA), while in the troposphere signal is manifested in the form waves Rossby ultralargas.Todo this is according to current theory porpagación wave Rossby.También demonstrates that, in the stratosphere during the winter season, the Rossby waves forced anomalies in the movement Brewer-Dobson, it is therefore more intense during "hot , "or El Niño phenomenon ENSO.Así identifying the ENSO as a major source of climate variability in extratrópico, and the lower stratosphere and mesosphere.

Author: ADAME CARNERO JOSE ANTONIO.
Year: 2004.
University: HUELVA.
Place of defense: FACULTAD DE CIENCIAS EXPERIMENTALES.
Place of preparation: FACULTAD DE CIENCIAS EXPERIMENTALES.

Summary: The year 2000 is designed and makes operating a network measurement of surface ozone in the province of Huelva, to be formed this four stations distributed strategically far, three in the coastal area and at a point inside a 50 km of line coast gives genre a database of ground-level ozone concentrations at which this study was performed. In order to make a correct interpretation of behavior delas ozone concentrations were analyzed regime winds in the area and the phenomenon of coastal breeze, as well as levels and behavior of other atmospheric parameters that can influence ozone concentrations. We have analyzed the seasonal cycles of ozone concentrations, changes daily, the maximum and minimum, and the relationship between ozone and various meteorological variables (temperature, humidity and wind) and atmospheric parameters (total ozone, oxides particulate matter and nitrogen). It has counted the number of exceedances of the threshold defined by the law and discusses persistencias of these exceedances. It has studied the behavior that shows the ozone under local conditions (conditions breeze). It analyzes every night, and have been studied in detail scenarios weather in the region caused high concentrations of ozone, known as situations episodicas.

Author: CARMEN MARIA SORDO GARCIA.
Year: 2005.
University: CANTABRIA.
Place of defense: E.T.S.DE INGENIEROS DE CAMINOS,C.Y P..
Place of preparation: E.T.S. DE INGENIEROS DE CAMINOS.

Summary: The Meteorology modern addressed numerical weather prediction in a wide range of time scales: from the popular predictions short (1-3 days) and medium-term (3-15 days), until predictions inter-anuales climate change obtained assuming different scenarios of radiative forcing ($ CO_2 $ duplication, and so on.). In recent decades there have been significant advances in numerical prediction in the short and medium term, and its projection regional downscaling techniques (combining the outputs directly from the models with observations passes available). Also, there have been significant advances in the development of global and regional scenarios of climate change. However, there has been a gap in the intermediate horizons of monthly and seasonal forecasting motivated by skepticism reliable predictions can achieve these outcomes. It was recently when he started to investigate this issue from an operational point of view, from knowledge of different sources of predictability, as the oscillation of Maden-Julian or El Niño. To this end, developed physical models of coupled atmosphere-ocean circulation that are solved numerically from an initial condition to provide a prediction for a period of six months. These models provided good results for the prediction of El Niño 1997/98. However, the results are still emerging and very specific cases except prediction in the tropics there are no clear indications on lla quality of numerical models of seasonal forecasting. It is still less awareness about the validity of the techniques applied to these predictions regionalization (there are a few statistical downscaling techniques adapted to this time scale, but lack of comprehensive validation). This thesis addresses this problem and provides an operational method for predicting seasonal regional in the tropics and mid-latitudes, combining direct departures of the most important seasonal prediction models used in European centers with statistical models of regionalization of the same . Presents an in-depth comparative study of both areas as compared to the predictions obtained direct departures from the model and compared with a method of predicting random, worthless. As the main result has been concluded that in the tropics can be obtained reliable predictions timely specific eras (strong ENSO episodes), while in middle latitudes only predictions can be obtained at intervals of lower resolution, in some cases associated with known phenomena teleconexiones in the tropics. The practical implementation of the results of this thesis is facilitated by the increasing availability of data from observations (for example, the network of stations National Institute of Meteorology has daily observations in over 6000 estacones distributed by Spain ), these data provide valuable statistical information from local climatology. There are also different rethought numerical models that contain atmospheric situations given by the same numerical model for a broad enough period of time (for example rethought ERA-40 made by the European Centrer for Medium-Rante Weather Forecast covers the period 1957 - 2002, while hindcast model seasonal System2 ECMWF covers perío 8 do 1987 - 409 2004). With all this information we can develop predictive models regional operating can be very useful in various socio-economic sectors that require this type of high-resolution forecasting to assess medium-term policy action to adverse weather situations (agriculture, energy , public health, etc..).

Author: Gómez Amo José Luis.
Year: 2005.
University: VALENCIA.
Place of defense: Departamento Fisica de la Terra i Termodinamica.
Place of preparation: Facultat de Física.

Summary: Aerosols play a very important role in the atmosphere in terms of the physical and chemical processes involved as well as the effects on climate and its impact on natural ecosystems. In a direct act of absorbing and reflecting solar radiation incident favoring the atmospheric warming or cooling. Indirectly lend its surface water molecules act as condensation nuclei, actively participating in the formation of clouds and changing the hydrological cycle. The great diversity of sources and mechanisms of formation of aerosols, both natural and anthropogenic, along with his great spatial heterogeneity and its temporal variability make his address detailed characterization can be an extremely complex task. Increasing anthropogenic activity, thanks to the automotive and industrial development, has been a source of constant and virtually unlimited insertion of particles in the atmosphere, especially near urban centers. In addition brought about a new way of understanding and treating aerosol pollutants, they along with some naturally occurring particles (dust, pollen, etc.). May seriously affect human health in the form of respiratory illnesses and allergies. The main objective of this work was to characterize atmospheric aerosols from spectrum measurements of solar radiation in three campaigns conducted in isolated field characteristics different climatic zones. Obviously there is no time series long enough to draw conclusions weather representing the areas under study. However, the results to draw conclusions distinctive in the type of aerosols. Moreover, they have been applied methodologies developed for the calculation of the optical properties of aerosols (aerosol optical thickness, size distribution, effective radius, and so on.) Has been studied and further its relationship with meteorological parameters, vertical profiles and situations synoptic to improve the interpretation of one's own actions. Level instrumentation has proposed a correction of the measures due to the effect of temperature in a way that improves the accuracy of Liquor - 1800, especially in the ultraviolet and infrared regions. The first campaign took place during the spring of 2002 in Sodankylà ¤, a small town situated in a boreal in northern Finland that according to the classification of climatic Kà ¶ ppen is part of a subarctic climate zone. As most important results is that, overall cargo aerosol observed is very low and therefore works with errors on the order of the steps. We have linked the characteristics of aerosols as the source of air masses and has been classified a short episode of "Arctic haze" that explains the increase in the aerosol optical thickness observed the first few days of campaign. This phenomenon is the accumulation of particles in the area due to the transport overview of small particles from industrial areas in mid-latitudes over the contribution of the particles due to the local atmospheric stability remain trapped in the lower layers. For two consecutive years, 2003 and 2004, SPARC campaigns were carried out in Barrax, a rural town near Albacete. These have been classified two situations typical weather in the Iberian Peninsula during the summer. A low thermal situation on the peninsula with influence of air masses from the Atlantic 8 in the qu a32 and both the aerosol optical thickness and the size distribution is held constant along the campaign SPARC-2003. In addition, the campaign SPARC-2004 begins with the same kind of synoptic situation of 2003, however the third day campaign has been a slight intrusion of dust particles Saharan origin, which is reflected in a substantial increase in addition to an optical thickness increasing the size and amount of coarse particles. The last campaign was in the month in March 2003 in the vicinity of the city of Marrakesh (Morocco). In general, values were obtained from optical thickness lower than expected because of the proximity of the Sahara desert. As for the distribution of particle size seems that local contribute equally to both modes. The campaign was governed by the influence of Atlantic origin characterized by optical thickness slightly higher and a significant growth in the volume of particles as your radio. Under influence of the interior of Africa are observed optical thickness minors and a decrease in the volume of large particles, this should be related to the transportation of mineral particles from the desert as it is hampered by the mountainous terrain and meteorology unique Atlas of the Cordillera. Finally, it suggests guidelines for the development of a new method of investment that allows the identification of the types of aerosols in the atmosphere from their properties microphysical and optical thickness. This method, still in its embryonic stage, has been applied to the results obtained in all the campaigns studied with experimental mixed fortunes. The method is well able to reconstruct the values of experimental optical thickness but requires some additional restrictions both mathematical and physical nature.

Author: ESCUDERO TELLECHEA MIGUEL.
Year: 2005.
University: BARCELONA.
Place of defense: FACULTAD DE FÍSICA.
Place of preparation: FACULTAD DE FÍSICA.