Chronicle of the Aral Sea and the Sub-Aral region

Geomorphological evidence for the Late Holocene evolution and the Holocene lake level maximum of the Aral Sea

“…Results of the GIS analysis confirm what Kes (1995) already recognised: the present basin topography rules out the Holocene lake level maximum of 73 m proposed by Boomer et al (2000). Whereas Kes (1995), or her primary sources, still assume that a higher lake level than 70 m would trigger overflow into the Caspian Sea, analyses using the digital elevation model SRTM-3 give a critical value of 64 to 65 m, which is also confirmed by topographic maps.…”

“…Pinkhasov (2003) accepts a maximum Holocene lake level of 73 m in his maps, although he sets it at a much younger date (3 to 4 ka BP). By contrast, both Kes (1995) and Létolle and Mainguet (1997) question a maximum lake level of 73 m.…”

“…Whereas Kes (1995), or her primary sources, still assume that a higher lake level than 70 m would trigger overflow into the Caspian Sea, analyses using the digital elevation model SRTM-3 give a critical value of 64 to 65 m, which is also confirmed by topographic maps. Above this level the basin starts to overflow, which, in turn, prevents the lake level from rising further.…”

“…Additional information is provided by Kes (1995) and Mainguet (1996, 1997). The palaeogeographical summary by Boomer et al (2000) lists various transgressions and regressions with intermittent phases of stability.…”

A High-resolution diatom-inferred palaeoconductivity and lake level record of the Aral Sea for the Last 1600 yr

“…Conditions in the montane regions themselves must also be considered, where climatic conditions control the rate at which melting glaciers and snowfields feed the Amu Darya and Syr Darya. Importantly, severe regressions may not only be linked to overall moisture availability across the region and the subsequent flow rate of the Amu Darya but also to the river's direction of flow, which since the late Pleistocene has altered (Kes, 1995;Boomer et al, 2000) due, in the main, to two possible factors: (i) the natural build-up of sediment within its bed, which may alternately divert the river away from and towards the Aral Sea and (ii) human activity, particularly irrigation and military conflicts that have previously diverted discharge away from the lake (Letolle and Mainguet, 1997;Letolle, 2002).…”