Temporal and spatial patterns of sea level in inland basins: Recent events in the Aral Sea

Abstract

We demonstrate in this paper that satellite altimeter data resolve the drop in the Aral Sea level during 1993–2000 of about 0.6 m per year resulting in a change of surface area from 35000 to 22000 km2 and volume from 270 to 130 km3. The sudden drop in the sea level of the Northern basin on 04.21.1999 resulting from dam break‐up is also clearly resolved. The temporal and spatial variability of sea level reveals response patterns which are characteristic for friction dominated shallow sea dynamics. The combination of salinity and sea‐level data enables to identify the major events of environmental transition, which are associated with the temporal variability in the total salt content: (1) a peak in 1993–1994, and (2) an increasing trend in the last decade. These events are indicative of an increase in the discharge of ground water, but could also reveal overestimated salinity estimates from recent observations.