%0 Conference Proceedings
%4 sid.inpe.br/mtc-m19/2012/08.16.18.23
%2 sid.inpe.br/mtc-m19/2012/08.16.18.23.52
%T Hydrological response of the Amazon basin to drought events of 1997/98, 2005 and 2010
%D 2012
%A Borma, L. S.,
%A Tomasella, Javier,
%A Cuartas, E. M,
%A Arraut, T. S. F,
%A Silva, D. A. Rodrigues,
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%B Planet Under Pressure Conference, (PUP).
%C London
%8 26-29 Mar. 2012
%S Abstracts
%K Amazon basin, drought, flooding.
%X While there is an increasing understanding on forest response to severe droughts episodes recently occurred in Amazon region (e.g. tree mortality rates, live biomass, CO2 exchanges and forest resilience), there has been not so many works on the hydrological response of the region to rainfall anomalies. The analysis of river discharges along the main stem and major tributaries during the drought episodes of 1997/98, 2005 and 2010 shows that they were of increasing intensities. Discharges well above the historical levels on the southern tributaries restricted the 1997/98 temporal and spatial drought coverage, lasting around 3 months during the low water period and being spatially restricted to the northern tributaries. The 2005 drought lasted the entire period of low water (4-5 months) and was mainly driven by the low discharges coming from the southern tributaries. The high water season presented discharges slightly above the historical means. Finally, the 2010 drought lasted 4-5 months. The discharges dropped to values well below the historical average during the low water and slightly below the historical average during the high water season, mainly driven by the southern tributaries. Additionally, the northern tributaries showed a strong decrease of the discharge during the preceding high water season, which may have affected the groundwater recharge, fully expanding the impact of decreasing rainfall during the dry season. An analysis of the dynamic of the flooding coverage using MODIS sensor shows that between 2000 and 2010, the smallest flooded area occurred in 2005 (36.000 km2) and 2010 (37.800 km2) years. The reduction in flooded area - and the associated increase in the area of exposed soil has a direct relationship with the lives of the riverine communities during extreme drought episodes, as indicated by the number of municipalities which declared state of emergency, according to the Civil Defense data.