CIMA   09099
CENTRO DE INVESTIGACIONES DEL MAR Y LA ATMOSFERA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Comparison of GLDAS Soil Moisture anomalies against the Standardized Precipitation Index over South America
Autor/es:
P. SPENNEMANN; J. RIVERA; C. SAULO; O. PENALBA
Lugar:
Montevideo
Reunión:
Conferencia; WCRP-LACC; 2014
Institución organizadora:
WCRP
Resumen:
Soil
moisture is a key variable of the earth-atmosphere system, that not only
reflects the soil conditions of a given region, but it also can modulate the
atmosphere from seasonal to synoptic time scales. This study aims to compare the
agreement between simulated soil moisture anomalies derived from the Global
Land Data Assimilation System (GLDAS version 1 and 2) with the Standardized
Precipitation Index (SPI). In this study, a verification of the soil conditions
simulated by GLDAS is carried out, which is of high relevance due to the lack
of observational soil moisture datasets over South America. A special interest of
this analysis is set on the southeastern part of South America (SESA, 35-25°S
latitude and 63-50°W longitude), which is part of the La Plata Basin (LPB), one
of the largest basins of the world and reservoir of high biological diversity /biological
wealth, where the agriculture is the main source of incomes. The results
obtained from GLDAS-1 and from GLDAS-2 indicate that the precipitation dataset
used to force the Land Surface Models (LSM), is of major relevance for
representing the soil conditions in an adequate manner. Nevertheless, it was
shown that CLM2 and NOAH LSM from GLDAS-1 had also a very good agreement, although they were forced with an inconsistent
climatologically dataset. Over the region of SESA, the closer relationship
between soil moisture and precipitation at 3-months time scales, points out
that precipitation is one of the main controlling factor upon the simulated
soil moisture, and therefore, upon agricultural droughts. Finally, and in
agreement with other studies and monitoring applications using simulated soil
moisture (e.g. the CPC Drought Monitoring), the potential usefulness of GLDAS
outputs for the analysis of droughts and their main features (i.e. spatial,
frequency and intensity) is documented and the development of new droughts
indices based on GLDAS over the South America is recommended for future works