La precipitación en Argentina subtropical y su relación con el monzón sudamericano

Ponencia presentada en: II Congreso de la Asociación Española de Climatología “El tiempo del clima”, celebrado en Valencia del 7 al 9 de junio de 2001[ES]El ciclo anual de precipitación en Argentina tiene características diferentes en distintas zonas. La región nordeste presenta lluvias intensas y poca variabilidad anual. La zona noroeste se caracteriza por lluvias en verano y la región sudeste está asociada a un ciclo semianual. La conexión entre la variabilidad interanual de la convección tropical sobre Sudamérica y la lluvia en Argentina subtropical en primavera y otoño es estudiada usando mediciones de radiación de onda larga saliente (OLR) obtenidas con radiómetro en los satélites NOAA para el período 1975-1997. Si el monzón comienza antes de lo esperado climatológicamente se observan lluvias superiores a lo normal en el centro-este de Argentina e inferiores a lo normal en el sur de Brasil en septiembre y el resultado contrario se observa si el monzón comienza después de lo esperado. Un monzón que termina antes de lo normal está asociado a lluvia intensa en el sur de Brasil, Uruguay y este de Argentina durante el mes de mayo. Estos patrones se deben a la acción combinada de la advección de humedad en capas bajas que produce la cercanía de la convección y tiende a aumentar la precipitación y a la subsidencia compensatoria que inhibe la lluvia.[EN]The mean annual rainfall cycle in subtropical Argentina has distinctive characteristics in different areas. The northeastern region is related to great rainfall and little variability along the year. The northwestern region has summer rainfall and the southeastern part of subtropical Argentina is characterized by a semi-annual cycle. The connection between the interannual variability of tropical convection over South America and rainfall in subtropical Argentina in spring and autumn is studied using outgoing longwave radiation (OLR) measurements obtained from the scanning radiometer aboard the polar orbiting NOAA operational satellites during 1975-1997. If the monsoon begins before than normal, rainfall greater than normal are observed in central-east of Argentina and less than normal in southern Brazil in September and the opposite result is observed if the monsoon is delayed. A monsoon that ends before than it is expected is related to great rainfall in southern Brazil, Uruguay and eastern Argentina. These patterns are due to the vertical motions caused by compensatory subsidence that inhibit rainfall or because of the water vapor advection toward the south that tends to increase precipitation

Estudio de las fluctuaciones y tendencias de la precipitación en el Chubut utilizando funciones ortogonales empíricas

Se analiza la información del Chubut utilizando desarrollos en funciones ortogonales empíricas de la precipitación en el período 1931-1960. El primer autovector refleja una leve tendencia positiva, con un máximo bien definido superpuesto a la misma en 1945; por sí solo, con su correspondiente conjunto de multiplicadores (que tienen una fuerte correlación positiva con la longitud, excepto en la zona costera donde se hace negativa) caracteriza en gran medida la precipitación media del período. El segundo autovector (cuyos multiplicadores muestran una correlación negativa con la latitud, que se acentúa cuando se excluye la zona cordillerana) se hace negativo entre los años 1933 y 1952 con un máximo pronunciado alrededor de 1957. Para este estudio se utilizó la reconstrucción de series cortas mediante funciones ortogonales empíricas, que permitió una descripción espacial de las fluctuaciones y tendencias durante el período consideradoThe information from Chubut is analyzed by means of empirical orthogonal functions of precipitation in the thirty years periods 1931-1960. The first eigenvector shows a slight positive tendency, with a well defined maximum in 1945 superposed on it; by itself, with the ensemble of its multipliers (which have a strong positive correlation with longitude, except in the coastal zone where it’s negative) it characterizes in great measure mean precipitation in this period. The second eigenvector (whose multipliers show a negative correlation with latitude, enhanced when the Cordillera de los Andes is excluded) is negative from 1933 to 1952, and has a significant máximum near 1957. In this work empirical orthogonal functions were used to assimilate and reconstruct short data series; this made possible a spatial description of fluctuations and tendencies of precipitation in the period'under study.Asociación Argentina de Geofísicos y Geodesta

Campos de precipitación de la provincia del Chubut (periodo 1931-1960)

Durante varios años el Centro Nacional Patagónico ha recogido información sobre precipitación de diversas fuentes y períodos, con particular énfasis en la proveniente de pobladores rurales, disponiendo actualmente de datos de más de cien localidades del Chubut, provenientes en general de diferentes períodos y presentando a veces series incompletas. Trabajos anteriores de los autores mostraron que la precipitación ha variado durante el presente siglo en forma diferente en distintas regiones de la Provincia; aun así, métodos elaborados en el Centro Nacional Patagónico permiten incluir series de períodos cortos (menos de 30 años)en el análisis de los campos de precipitación en el período elegido 1931-1960. Se utilizan resultados de otros trabajos de los autores para completar series defectuosas, y se trazan mapas estacionales y anuales de precipitación en base a la información citada y a las características del relieve. En lugares con información escasa o nula se utilizan datos de fuera del período 1931-1960, como referenciaThe Centro Nacional Patagónico has gathered precipitation data of over a hundred locations of Chubut. Many of them are coming from countrymen. The data covers different periods and most of them are incomplete. In a former paper, the authors have shown that precipitation has undergone significant changes during this century in a different way for different regions. A method developed in the Centro Nacional Patagónico, allows the assimilation of short series. Annual and stational maps of mean precipitation of Chubut for the normal period of thirty years (1931-1960) are shown.Asociación Argentina de Geofísicos y Geodesta

Development of structural layers PVC incorporating phase change materials for thermal energy storage

The use of poly(vinyl chloride) (PVC) structural layers incorporating phase change materials (PCM) for latent heat thermal energy storage (LHTES) has become more attractive in the recent years compared to other supporting materials. In this study, PVC layers with different types of PCM were prepared using blending and compression moulding methods. Two types of synthesized PCM, one based on paraffin and calcium carbonate (PCM@CaCO3) and the other on paraffin, silica and graphene oxide (PCM@SiGO) have been developed to enhance the thermal conductivity of the PVC matrix and thus achieve a more effective charging and discharging process. PVC layers prepared using a commercial PCM (PCM@BASF) were also prepared for comparison. SEM images and DSC results reveal homogeneous distribution of the PCM in PVC layers and that most PCM particles are undamaged. The shell material (in the case of PCM@BASF) and the shape stability (in the case of synthesized PCM@CaCO3 and PCM@SiGO) prevent leakage of molten paraffin during the PVC layer production. The thermal conductivity profile of the PVC layer without PCM have a decreasing tendency with the temperature increase when determined using different measurement approaches, the transient plane heat source method (HotDisk Analyser, TPS 2500 S) and thermal flux meter method (steady-state method). However, for PVC layers with PCM the thermal conductivity profile shows a different behaviour when the mean surface temperature of the specimen is below the phase change transition temperature range (increasing tendency). During phase change transition (18–26 °C), the thermal conductivity presents two distinct tendencies. Firstly, the thermal conductivity reveals a decreasing tendency as the mean temperature of the specimen rises and afterwards an increasing tendency. Secondly, when the mean surface temperature is above the phase change transition temperature range, the thermal conductivity profile shows a decreasing tendency, independent of the PCM. The mechanical properties of PVC layers were also assessed and the results obtained revealed that the incorporation of PCM into the PVC matrix reduces the mechanical performance of the composites, however for LHETS applications not subjected to high tensile stress levels (over 1 kPa), this is not a significant drawback.publishe

Use of active caspase 3 and tunel assays to estimate embryonic quality in in vivo Santa Ines ewe embryos.

Edição dos proceedings da Annual Conference or the International Embryo Transfer Society, Orlando, Florida, 2011

NUMERICAL SIMULATION OF THE MOORING PROCEDURES OF THE BGL-1 PIPELINE LAUNCHING BARGE

ABSTRACT The objective of this paper is to present the application of a computational tool intended to help the crew of the BGL-1 pipeline launching barge to develop safe mooring procedures. This tool is able to calculate the deformed catenary configuration of all mooring lines, regarding the subsea layout and the local environmental conditions, and taking into account one or more buoys attached to the mooring lines in order to avoid interference and accidents with subsea obstacles. One of the main characteristics of this computational tool is the fact that it is able to incorporate the correct definition of the seabed from bathymetric curves, and to automatically consider the position of the subsea obstacles, and possible interferences between the mooring lines and the obstacles. This is performed through a specialized interface with the SGO (Obstacles Management System) database system. This system, developed by Petrobras, contains frequently updated information about the bathymetry and position of subsea obstacles, gathered by a special vessel equipped with a ROV (Remote Operated Vehicle). Case studies will be presented, in order to illustrate the application of the system to the design of actual mooring procedures

Climate change 2014 : impacts, adaptation, and vulnerability

Current and future climate-related drivers of risk for small islands during the 21st century include sea level rise (SLR), tropical and extratropical cyclones, increasing air and sea surface temperatures, and changing rainfall patterns (high confidence; robust evidence, high agreement). Current impacts associated with these changes confirm findings reported on small islands from the Fourth Assessment Report (AR4) and previous IPCC assessments. The future risks associated with these drivers include loss of adaptive capacity and ecosystem services critical to lives and livelihoods in small islands.peer-reviewe

Effect of time of onset of follicle-stimulating hormone treatment on superovulatory response and embryo yield of santa ines ewes during breeding season.

Proceedings of the Annual Conference of the International Embryo Transfer Society, Hannover, Germany, 19-22 January 2013. Papers and Abstracts for Poster Presentation