Dissertação
Escoamentos de retorno de umidade na Bacia do Prata
Fecha
2015-05-22Registro en:
ESPINDOLA, Felipe Daniel Cristo. Flow of moisture return in the Bacia do Prata. 2015. 75 f. Dissertação (Mestrado em Geociências) - Universidade Federal de Santa Maria, Santa Maria, 2015.
Autor
Espindola, Felipe Daniel Cristo
Institución
Resumen
This study evaluated the seasonality of moisture supply on part of the Bacia do Prata (BP) in
the context of transient anticyclones east of the Andes, phenomenon that receives the name
of moisture return (RU). This phenomenon has two main phases: first, occurs the approach
of a transient anticyclone and establishment of air cold and dry mass on the study region and
the second with the return to this region of a warm and moist air due to displacement of transient
system for lower latitudes in the South Atlantic. Were utilized Reanalysis of Climate
Forecast System Analisys (CFSR) data for the period between 1990 and 2009. For the selection
of candidates a RU were analyzed time series in four different sectors of the BP of the
following variables: reduced pressure at mean level sea (PNM), specific humidity integrated
between 1000 and 700 hPa (Uint), meridional wind at 850 hPa (V850) and air temperature
at 1000 hPa. Then the candidate events undergo a synoptic analysis for selection only of the
cases RU. For the confirmed cases were performed seasonal analysis of the synoptics field
average of the variables temperature and specific humidity at 850 hPa (T850 e q850), V850 e
PNM e the thickness between geopotential heights 500 hPa and 1000 hPa (ESP) and also was
calculated the divergence of moisture flux vertically integrated in a domain that defines part
of BP. Lastly, rainfall estimates by remote sensing by the method Center Morphing Method
(CMORPH) between 2003 and 2009 were used to determine the seasonal pattern of rainfall
in BP and in each of the sectors used in this work. The results show greater number of RU
events in the winter months followed by spring, Also in the winter is observed changes more
intense air masses between different phases of the RU and a higher moisture effectiveness for
BP in the in phase 2 of RU. The precipitation in phase 2 of RU contributed to more intense
rainfall in summer and in winter it is important for the total number of days with precipitation.