Caspian Sea 2011

2010

evident in 2001. On average, the seasonal sea level variability did not exceed 25 cm during the period 1992-2003 (Lebedev 2005). While there is general scientific agreement on the cause of such fluctuations, there is no agree- ment as to the extent climate change affects such events. At present, only limited assessments of the implications of climate change are available. Meanwhile, computer modeled estimates carried out in littoral states vary considerably - some pre- dicting a drop of as much as 4.5 m while others forecast a rise of as much as 6.4 m. Even given maximum water inflows into the Cas- pian Sea, it seems very unlikely the sea level will exceed the marks of -25 m during the short to me- dium term (Panin 2006). Applying different computer modules, based on an estimate of a doubling of carbon dioxide con- centrations, Kazakh researchers concluded that with an annual water consumption (from rivers) of 40 km 3 : the Caspian Sea may rise by 4.7 m ac- cording to the CCC model, by 6.4 m according to the UKMO model, and by 1.0 m according to the GFDL model (Kudekov 2006).

However, modeling analysis must to be han- dled with caution. In the past, forecasts have resulted in expectations of a catastrophic sea level decrease and the planning of mitigation projects. Such forecasts have been contradicted by events: a considerable rise in sea levels (by almost 3 m since 1977) has caused significant damage (UNEP, 1995). Renssen as well as Elguindi and Giorgi use the model based on the A1b anthropogenic emission scenario and predict a 4.5 m sea level decrease in the 21st century (Renssen et al, 2007; Elguindi and Giorgi, 2007). They say that potentially dev- astating consequences for the economy and en- vironment of the region are likely to be caused by climate change and increased evaporation loss from the basin (particularly over the sea) — ex- ceeding cold season precipitation in the area. And if fluctuations in sea level are in the range of elevations of - 25 to - 29 m, coastal areas are likely to suffer serious environmental conse- quences, curtailing economic activity. The Caspian littoral states are understand- ably concerned about the financial and human costs of fluctuations in sea level. In June 1992,

Changing Caspian

Metres below sea level

-24.8 -25.2

2006

-25

Variation in sea level observed by instruments

-26

Average surface level

-27

-27.9

Forecasts calculated by

-28.0

-28

R. K. Kilge B. L. Malinin

Geography Institute of National Science Academy of Azerbaijan and Baku Science University hydrometeorology department

-29

FORECASTS

I. A. Shiklomanov

1840

1860

1880

1900

1920

1940

1960

1980

2000

2020 2040 2050

Source: Panin, G., N., Transboundary Diagnostic Analysis. Climate Change and Vulnerability Assessment Report for the Caspian Basin, 2007.

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