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| Titel |
Geodynamical processes in the channel connecting the two lobes of the Large Aral Sea |
| VerfasserIn |
E. Roget, P. Zavialov, V. Khan, M. A. Muñiz |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1027-5606
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| Digitales Dokument |
URL |
| Erschienen |
In: Hydrology and Earth System Sciences ; 13, no. 11 ; Nr. 13, no. 11 (2009-11-26), S.2265-2271 |
| Datensatznummer |
250012063
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| Publikation (Nr.) |
 copernicus.org/hess-13-2265-2009.pdf |
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| Zusammenfassung |
| Reasons for the existence of the channel connecting the two lobes of the
present Large Aral Sea are discussed. In situ measurements in 2005 show that
differences between the measured depths and those contained in the available
digital bathymetry of the lake are considerably different at the channel
(7.5±0.9 m, at nine measurement stations along it) and at the northern
part of the eastern lobe (1.6±0.3 m, at six stations from the western
to the eastern shore). Differences in the misfits observed in the two zones
are discussed and thought to be a consequence of the variation of the
transversal area of the channel as it enters the eastern lobe, which would
affect the flow velocity and thus the strength of the erosion process at the
bottom. Field data together with satellite images have been used to modify
an original digital bathymetry of the lake and have been implemented into a
3-D hydrodynamical model. A numerical simulation shows that a wind of 12 m/s
blowing from the east (112°) generates velocities of up to 45 cm/s in
the channel, allowing denser water from the eastern lobe (salinity: 132 g/kg)
to flow about 38 km towards the fresher western lobe (salinity: 98 g/kg)
in one day. The effect of the inflow on the vertical structure of the
western lobe is also illustrated. Although nowadays the channel will be soon
a thing of the past, in a more general context, the Aral Sea is presented as
an example showing that geomorphologic and geophysical processes, along with
hydrological and atmospheric processes, must be taken into account for
short-term predictions. |
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