Time filter

Source Type

Cretaux J.-F.,French National Center for Space Studies | Letolle R.,University Pierre and Marie Curie | Kouraev A.,University Of Toulouse Ups Omp Pca | Kouraev A.,State Oceanography Institute St Petersburg Branch
Handbook of Environmental Chemistry | Year: 2010

The Aral Sea has drastically shrunk over the past 50 years, largely due to water withdrawal from the Amudarya and Syrdarya rivers for land irrigation. If one were to look back over the Holocene,1 the paleolimnology of the Aral Sea is however already marked by the occurrence of several phases of regression and transgression. They resulted partly from climate change, for tectonic reasons, and over the last 2,000 years anthropogenic actions also played a role. After a short review of the paleohistory of the Aral Sea, we will focus on a description of the causes and magnitude of episodes of historical (last 100 years) Aral Sea level variability. The Aral Sea has been marked since the middle of the last century by a process of desiccation due to increase of water intake from the Amudarya and Syrdarya rivers for agricultural purposes. This led to the separation of the Aral Sea into two (in 1986–1987) and then four (in 2009) water bodies. Measurements of Aral Sea water level and surface and water balance were carried out by both in situ gauges and remote-sensing satellite data. This allows for a better understanding of the seasonal, interannual, and decadal trend in Aral Sea water storage variations. © Springer‐Verlag Berlin Heidelberg 2010.

Meyssignac B.,University Of Toulouse Ups Omp Pca | Meyssignac B.,French National Center for Space Studies | Lemoine J.M.,University Of Toulouse Ups Omp Pca | Lemoine J.M.,French National Center for Space Studies | And 7 more authors.
Geophysical Research Letters | Year: 2013

Several recent studies have shown evidences for large water transfers in the climate system at interannual to decadal time scales, in particular during El Niño-Southern Oscillation events. In this study, we investigate further these water transfers and their signature in the gravity field. We analyze variations of the low-degree spherical harmonics C2,0 (Earth's oblateness), C2,2, and S2,2 (eccentricity at the Earth's equator) from satellite laser ranging data during the 19 year period 1993-2012. We also estimate the water mass transfers in the climate system using satellite altimetry corrected for the steric effect, atmospheric reanalysis, and land hydrology models. We find a large signal in the water mass redistribution during the 1997/1998 El Niño which is consistent with an increase of the ocean mass in the tropical Pacific, a decrease of water storage in the Amazon Basin, and an increase of water storage in the Congo Basin. © 2013. American Geophysical Union. All Rights Reserved.

Discover hidden collaborations