Présentations Colloques

Oral Presentation
5.02
Session 5.02: Groundwater and global change
Tales Carvalho Resende, Longuevergne Laurent
Assessing the impact of climate variability in large aquifers
NASA's Gravity Recovery and Climate Experiment (GRACE) - first satellite mission able to monitor total water storage changes (including groundwater) remotely – has provided new insights of the dynamics of large aquifers (>100 000kmC) since 2002. However, given that the dynamics of groundwater are not solely a function of temporal patterns in pumping but also a function of internannual to multidecadal climate variability, a longer observation time than the one GRACE analyses currently permit is required to separate the respective impacts of anthropogenic activities (land use changes, abstraction) and climate on water resources. Thus, there is a need to extend storage information provided by GRACE to the “past” to better evaluate the current and future evolution of groundwater resources.****This study aims at paving the way to better water management decisions and policies in large aquifers by “reconstructing” past groundwater storage changes as a cornerstone to provide a first quantitative evaluation of the potential effects of anthropogenic activities and climatic oscillations cycles such as the El Niño Southern Oscillation (ENSO) (2–7 year cycle), Pacific Decadal Oscillation (PDO) (10–25 year cycle), and Atlantic Multidecadal Oscillation (AMO) (50–70 year cycle) on large aquifers (area > 100 000 kmC) located in arid semi-arid and temperate regions. Validation is carried out by comparing obtained modeled results with GRACE groundwater storage changes, and ground-based measurements.****This study is part of the UNESCO International Hydrological Programme (IHP) research project on groundwater and climate change (GRAPHIC).
France