Seasonal water storage and delay across continents: Patterns and drivers

SYLVAIN KUPPEL; YING FAN; ESTEBAN G. JOBBÁGY

Vienna

Conferencia; EGU General Assembly; 2016

European Geosciences Union

Storage and delayed evapotranspiration (ET) of precipitation (P) inputs by land ecosystems is critical regulating the timing and stability of plant production and the multiple ecological and economic processes that it supports. The extent to which actual ET (AET) can decouple from P inputs depends on the ecohydrologic system capacity to store water. This decoupling and its associated storage requirement can be particularly relevant at the seasonal scale in regions where, for instance, rainfalls are highly seasonal and/or P and potential ET (PET) are seasonally out of phase. Focusing on the 2003-2010 period, we explore, first, where on Earth this decoupling is likely to occur from a climate perspective by assessing the magnitude and duration of the expected seasonal land water transfers. These climate-based predictions are then compared with independent evidence derived from ecological remote sensing observations (seasonal vegetation activity patterns), hydrological satellite retrievals (seasonal water storage patterns) and terrain characteristics datasets, in order to analyze how land surface processes alter the ?potential? seasonal hydrologic buffer provided by the local climatic conditions, in terms of both volume and residence time. This analysis helps outlining the expected seasonal response of the land water cycle in the frame of likely climate and land use changes.