Wikindx Resources

Communication incl. Poster: BibTeX citation key:  Grippa
Grippa, M., Kergoat, L., Frappart, F., Araud, Q., Boone, A., De Rosnay, P., Lemoine, J.-M. & ALMIP Working Group. 2009. Evaluation of land water storage changes over West Africa estimated by GRACE and by land surface models. Work presented at Third International AMMA Conference, July 20—24, at Ouagadougou, Burkina Faso.
Added by: roussot 2009-10-19 21:03:00
 B  
Categories: Environment and Climate Monitoring, Land surface processes, Land surface-atmosphere feedback, Water cycle
Creators: ALMIP Working Group, Araud, Boone, Frappart, Grippa, Kergoat, Lemoine, De Rosnay
Publisher: African Monsoon Multidisciplinary Analyses (Ouagadougou, Burkina Faso)
Collection: Third International AMMA Conference

Number of views:  1019
Popularity index:  53.8%
Maturity index:  published

 
Abstract
Land water storage plays a fundamental role on water budget particularly in regions where the coupling between land surface and the atmosphere is important such as West Africa. Also water availability in the root zone is fundamental for monitoring and modelling vegetation development. However, measurements of the land water storage are scarcely available at regional -global scale, particularly in endorheic regions such most part of the Sahel.
The GRACE satellite mission provides an accurate measure of the gravity field variations from which terrestrial water storage variations can be derived. However, its retrieval is not straightforward and different methods are employed resulting in different water storage estimates. On the other hand, water storage can be estimated by land surface modelling but significantly different results can be reached by using different models.
The first objective of this work is to evaluate the land water storage estimations by GRACE and by an ensemble of land surface models (in the framework of the AMMA Land Surface Intercomparison Project, ALMIP). Despite the not negligible differences within the different GRACE solutions and within the different results by the ALMIP models, the analysis of the seasonal evolution of water storage over West Africa shows a good agreement between satellite and models estimates. Moreover, the satellite data reproduce the modeled interannual variability over the Sahel during the study time period (2002-2007).
The second objective of this work is to use the available information on water storage to better understand the water balance variability and its impact on the West African ecosystems. In particular, we analyze the relationship between the water storage dynamics and the vegetation development estimated by the remote sensing observations (NDVI), and we discuss its implication for modeling the vegetation phenology at regional scale.
Added by: roussot