Application of numerical models for the study of surface water bodies on the pampas region

ALIAGA, VANINA; FERRELLI, FEDERICO; PICCOLO, MARÍA CINTIA; PERILLO, GERARDO

Bahía Blanca

Workshop; Global Lake Ecological Observatory Network; 2013

Instituto Argentino de Oceanografía

Numerical models and satellite information are important tools to characterize the climate in a region, while the climate is an essential element to understand the dynamics of water bodies. We studied the evolution of a set of shallow lakes (Chasicó, Paso de las Piedras, las Encadenadas del Oeste, La Picasa and Chascomús) distributed along a climatic gradient. The aim of the study was to compare the changes occurred in those lakes based on results obtained from numerical models and information from satellite images (LANDSAT 5 and 7). Data from the Reanalysis (NCEP / NCAR) and Bioclim models were processed for each lake. Dry, wet and normal years were identified within the period 1981-2012. The occurrence of extreme events was studied by the Quintiles and Normal methods. The results showed that the numerical models represent accurately the climate of the Pampas region. In general, the lake area was directly related with the amount of precipitation. For example, in the Encadenadas del Oeste, the lake area presented an increase of 4l946.4 ha in a very wet year (1991) and a decrease of 12726.5 ha in a dry year (2008) compared with a normal one (2006). To the south, in the semiarid region of the Pampas region, the Chasicó lake presented a decreased of 126.8 ha in a very dry year (2008) compared with a normal one (1995). Similar results were found in the other lakes. Climate information derived from numerical models represented the climate variability of the Pampas water bodies. Remote sensing and free online acquisition and availability of the models make these tools useful when weather stations are not available over the region.