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B. Bauer-Marschallinger, W. Dorigo, W. Wagner:
"How Oceanic Oscillations Drive Soil Moisture Dynamics in the Southern Hemisphere: An Analysis of the 35-Year-long ESA-CCI Soil Moisture Record";
Poster: The Climate Symposium 2014, Darmstadt, Germany; 2014-10-13 - 2014-10-17.

Global warming is expected to accelerate the global hydrological cycle. Precipitation distributions are likely to change, with intensification of both dry and wet conditions leading to an increased risk of aridity and droughts and more extreme rainfall events and floods.
The southern hemisphere is especially vulnerable to amplified dynamics of terrestrial moisture supply. The latter is strongly connected to oceanic and atmospheric oscillations (climate modes) such as the El Nino-Southern Oscillation (ENSO), the Indian Ocean Dipole (IOD) and the Southern Annular Mode (SAM). Recent research found evidences for climate mode - induced dry and wet spells due to alteration of precipitation patterns and terrestrial evapotranspiration. In this domain, surface soil moisture (SSM) is a valuable observation as it integrates terrestrial climatic and hydrologic conditions.
Here, we use a global 35-yr dataset of remotely sensed SSM to examine the hydrological variations in South America, Africa and Australia for the period 1978-2013. On this data, we apply complex empirical orthogonal function (CEOF) analyses to extract independent SSM signals in form of paired spatial and temporal functions, which are then subject to analysis of how they relate to climate modes. Extracted climate mode - induced signals are foreseen to improve long-term trend analysis of SSM and bear potential for intraseasonal prediction.