The level of water in the Caspian Sea has decreased by more than two meters in the last 15 years, the head of Iran National Cartographic Center said.
“The Caspian Sea’s water level has reached -29 meters (relative to that of the Baltic Sea). The Baltic Sea statistic is used as a reference point to measure fluctuations in Caspian water level,” Ali Javidaneh was also reported as saying by Mehr news agency.
Due to the decline of water level, a considerable retreat of the sea and increase in the coastal area have occurred in the northern coasts of Iran.
This problem has caused a significant increase in the area of the beach along more than 850 km of the coastline.
Global warming is one of the major factors that has a direct effect on the rate of evaporation and loss of water from the surface of the Caspian Sea and the evaporation has not been balanced by either river discharge or precipitation.
The Volga River (Europe’s largest in terms of discharge that runs through Russia) is the largest tributary of Caspian Sea and provides 85% of its water (260 billion cubic meters a year). However, its water inflow to the sea has also decreased.
Other tributaries, which account for the balance of the inflow of water (about 60 bcm) are the Koura River that flows through the Caucasus Mountains, Ural River that passes through Russia and Iranian rivers, namely Atrak, Haraz and Sefidroud.
If the current trend of the water reduction process continues, it is expected that further retreat of the sea happen in the future.
Moreover, mega structures being developed by the Caspian Sea littoral states (Iran, Russia, Azerbaijan, Kazakhstan and Turkmenistan) on the tributaries of the sea will substantially reduce water inflow into the sea in the long run.
Close to 200 dams and other huge structures [floodgates and levees] are being built on rivers that feed the sea and would take a toll on the world’s largest lake upon completion.
The Caspian Sea is a closed water body and the largest of its kind in the world. It experienced a massive drop in water level in the late 1970s but normalized in 1991. However, the water level has been gradually dropping since then.
--- Territorial Waters
According to reports, declining Caspian Sea levels have also exacerbated the loss of territorial waters in Iran.
Satellite-based studies have shown that the level of Iran’s territorial waters is less than the global average and declining gradually.
A country's territorial waters are parts of the sea close to its coast, which are recognized by international agreement to be under its control.
In addition to irreparable ecological harm, the lowering water levels in Caspian Sea have led to the shrinkage of territorial waters.
The situation cries for action, but possibilities are limited. Rising global CO2 levels, the main driver of climate conditions causing the Caspian crisis, can only be dealt with global agreements.
In Soviet times, large-scale water diversions from Siberian rivers were proposed to deal with the shrinking Aral Sea to the east. But such large works – in the case of the Caspian Sea – come with huge ecological and geopolitical risks.
Nevertheless, action is necessary to safeguard the Caspian Sea’s unique biodiversity and the livelihood of the people who live around it.
