How the Caspian Sea Shrinks Under Climate Change Pressure

Between Europe and Asia lies the Caspian Sea, and it is shrinking. The lake suffers the impacts of climate change, resulting in widespread devastation to its biodiversity and the communities surrounding it.

The Shrinking Lake

With an estimated coverage of 386,400 square kilometers, the Caspian Sea is considered the largest inland body of water globally. It is situated in both Europe and Asia, and bordered by Kazakhstan, Russia, Azerbaijan, Iran, and Turkmenistan.

However, the lake is shrinking. A study using satellite altimetry measurements finds that between 1996 and 2021, the water level declined at an approximate rate of 1.5 meters/26 years. The decline particularly intensified from 2006 onward, with a 1.4 meters/16 years rate, or approximately 9 centimeters/year. If this rate continues, the water level is expected to drop by approximately 7 meters by the end of the 21st century.

Other studies have also examined this water level fluctuation with various results and projections. Despite the varying results, many researchers have attributed the decline in water levels to decreased precipitation and increased evaporation resulting from climate change. Heavy pollution from the oil and gas extraction activities and industrial waste also poses a significant threat.

Impacts on Biodiversity and Communities

The Caspian basin hosts a unique ecological system. There are over 400 endemic species, including six species of sturgeon and the Caspian seal, as well as various migratory birds. For surrounding communities, the lake also serves as a source of livelihoods, supporting commercial fisheries, shipping and transport, as well as agriculture and industry. Additionally, the Caspian Sea helps regulate temperature and air quality in the area.

Therefore, the shrinking lake will have significant repercussions for biodiversity and the surrounding communities. Research led by the University of Leeds finds that declining water levels will significantly reduce the breeding habitat for Caspian seals, which are already listed as Endangered by the IUCN. The decline can also lead to the loss of coastal lagoons and reed beds, which are breeding grounds for sturgeon and other fish species.

Furthermore, the research’s findings indicate that settlements, ports, and industrial facilities will be abandoned in the following years as the water becomes more shallow, especially in the northern Caspian, which means loss of livelihoods. Additionally, the exposed dry seabed is likely to release dust containing industrial contaminants and salt, which can pose a threat to human health, as seen in the Aral Sea.

Safeguarding the Caspian Sea

Climate change has brought unprecedented issues globally, causing the Earth’s ecosystems and our society to crumble under its pressure. Immediate action is required to address these issues and prevent further collapse.

The deterioration of the Caspian Sea necessitates immediate action grounded in collaboration and research. The five countries surrounding the lake signed the Tehran Convention in 2003, which was subsequently ratified in 2006, establishing the requirements and mechanisms for environmental protection of the lake. This highlights the importance of regional cooperation and transboundary collaboration in safeguarding ecosystems and livelihoods. Furthermore, efforts to understand the lake’s water level changes must also continue through robust monitoring activities and research.

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