Scientists, in a study published in a scientific journal, concluded that the drying up of the Caspian Sea, the world's largest enclosed body of water, is entirely due to human-caused factors.
The study, published in the journal "Earth's Future," warned of serious environmental and economic consequences if the current situation continues.
The study showed that water flow into the Caspian Sea has declined sharply over the past three decades, even though rainfall in the Volga River basin, the sea's main source of water, has increased slightly. Conversely, rising temperatures in the region have led to increased evaporation rates, but this phenomenon accounts for only about 40 percent of the recorded water loss.
The researchers pointed out that the largest part of the shrinkage is related to human activity, as the Volga River has been subjected over decades to extensive changes including the construction of dams and reservoirs, irrigation projects, industrial uses and river navigation, which have radically changed the hydrological characteristics of the basin.
The study added that part of the water that used to reach the Caspian Sea is now being diverted in the upper reaches of the river, noting that the Volga-Don canal, despite its economic and geopolitical importance, contributes to the depletion of the sea's water resources.
According to the study's data, the Caspian Sea's water level has dropped by about two meters since the mid-1990s, from 26 meters below sea level to 28 meters, while its area has shrunk by about 24,000 square kilometers, equivalent to 5.5 percent of its total area, with a loss of about 630 cubic kilometers of water.
The shallow northern part of the Caspian Sea is the most affected, despite its great environmental importance as a major habitat for fisheries, wetlands, bird migration routes and sturgeon breeding grounds, which provide the bulk of the world’s black caviar production.
Researchers warned that the enclosed nature of the Caspian Sea prevents it from compensating for its losses on its own, at a time when political differences between the five countries bordering it are hindering the establishment of a binding system for environmental monitoring and data exchange, despite agreements signed between them, including the Convention on the Legal Status of the Caspian Sea concluded in 2018 in the city of Aktau.
Scientists pointed out that the Caspian Sea has not yet reached the stage reached by the Aral Sea, which witnessed a widespread environmental collapse, but the warning signs have become more evident, calling for the establishment of a transparent system for managing water resources, which requires riparian states to disclose the quantities of water withdrawn from rivers feeding the sea for agricultural and industrial purposes.
