in order to determine the synoptic pattern of heavy and extreme precipitations on the southern coast of the caspian sea, precipitation characteristics of the caspian region were investigated by the use of eight synoptic stations data. considering the percentage thresholds, the days with heavy and extreme precipitations were determined for a 10 year period (1994-2003). since more than 75% of day...

Tides are the main type of sea level variability in the world oceans. However, oceanic tides penetrate weakly, or do not penetrate at all, into enclosed basins such as the Baltic, Black, and Caspian seas. Consequently, only directly forced tides are formed in these basins. Long observation time series (up to 123 years in the Baltic Sea and 38 years in the Black and Caspian seas) at numerous sta...

political geographic changes of the caspian region due to the independence of the states of the soviet :union: in 1991, has created changes in the geopolitical situation. iran and russia's policies in order to maintain and extend their dominance on the region, and the performance of azerbaijan, turkmenistan and kazakhstan in the field of economic progress, to achieve greater independence a...

after the soviet union fragmentation, the attentions of regional and international countries have turned to this region for oil and gas discovery in the caspian basin. after that, this region enjoys more geopolitical importance increasingly. therefore, the main question is:” what factors can influence the new geopolitics of the caspian basin?” it seems that, some issues such as the lack of a...

Remote measurements of different environmental parameters received during last 30 years are used for the synthesis of a Complex Simulation Model (CSM) describing the combined water regimes of the Aral-Caspian System (ACS) including the consideration of aquatic and climatic natural processes. The problem of stabilizing the sea levels of these two water bodies is modelled and a solution obtained ...

the geomorphology is an important branch of natural geography that its goal is promotion of human life, ultimately. the geomorphic processes have considerable impact on human life, and opposing, human activities and behaviors have its impacts on the geomorphologic units and geomorphologic processes, enhancing the above argument. the gilan county, at its geographic position; embraced by two stru...

The micropyle number in the ova of sturgeon species from the South Caspian Sea was investigated. The study was conducted on female broodfishes of three species of sturgeon (Persian sturgeon Acipenser persicus, Stetates sturgeon A. stellatus and great sturgeon Huso huso) included 44 Persian sturgeon, 13 stellate sturgeon and 8 great sturgeon specimens. Fifty eggs were randomly collected from eac...

Sturgeons (Order Acipenseriformes) represent an extremely valuable natural resource that is now facing depletion. In the current study we evaluate if the traditional classification in subspecies of Acipenser gueldenstaedtii, Acipenser stellatus and Huso huso, endemic to Ponto-Caspian region is sustained by molecular analysis and if these represent Evolutionary Significant Units (ESUs) that shou...