The sustained decline in the level of the Caspian Sea observed in recent years is having a serious impact on coastal areas, infrastructure facilities, shipping, and ecosystems.

This was stated in an interview with AZERTAC by Said Safarov, Head of the Laboratory of Caspian Sea Geography at the Institute of Geography of the Ministry of Science and Education, Doctor of Geographical Sciences.

The scientist noted that the Caspian Sea, the world’s largest enclosed body of water, has no direct connection with the world’s oceans, which means that its level changes under the influence of various natural and anthropogenic factors.

“Throughout history, both sharp declines and rises in the sea level have been observed. Since 2006, however, the level of the Caspian Sea has been declining continuously, and compared with 2005, the decrease has already exceeded 2.5 meters. During different geological periods, tectonic processes played the main role in changes in the Caspian Sea level. Over the past several thousand years, however, climatic and hydrological factors have had a greater influence. At present, changes in the Caspian Sea level are determined by its water balance. The inflow consists mainly of water brought by rivers and precipitation falling on the surface, while the outflow consists of evaporation from the surface and water flowing into the Kara-Bogaz-Gol Bay.”

According to Said Safarov, river discharge has played a particularly important role in fluctuations in the Caspian Sea level over the past several thousand years, with the Volga River being especially significant.

“Since the 1950s, numerous large reservoirs have been constructed in the Volga River basin, with a combined surface area of more than 36,000 square kilometers. Since the 1980s, evaporation from the surface of these reservoirs has increased sharply due to rising temperatures. At the same time, higher temperatures have also increased demand for water. Growing demand for water in industry, agriculture, and households has also affected the formation of river discharge.”

The scientist also stated that it would be incorrect to claim that a decrease in precipitation in the Volga basin is the main reason for the decline in river discharge. According to him, studies show that there has been no statistically significant change in the amount of precipitation in the Volga basin over the past 30–35 years.

He also noted that the sources of pollution in the Caspian Sea have previously been studied extensively.

“Within the framework of a European project, pollutants entering the Caspian Sea through rivers, drainage systems, and sewage networks were studied, and the results were published in a report. Currently, the Institute of Geography is conducting research into the factors affecting fluctuations in the Caspian Sea level, changes occurring in coastal areas, and monitoring of the sea. Field studies have been conducted in the southern regions of Azerbaijan, particularly in the territories of Astara, Lankaran, and Masalli districts. The main objective of these studies was to accurately determine how far the sea has retreated in different areas as a result of the decline in its level.

“These changes can be identified using satellite imagery and various measurement methods. However, to achieve greater accuracy in our research, we used GPS equipment capable of centimeter-level measurements. We rented this device for one day and, during our field studies, were able to measure how far the coastline had retreated in different areas as the sea level declined. These measurements enabled us to obtain more accurate results.”

According to him, both a sharp decline and a rise in the Caspian Sea level affect coastal infrastructure. These changes also have significant consequences for the ecosystem.

Addressing problems in the shipping sector, the scientist cited Baku Bay and the Dubendi area as examples. He noted that the shallowing of the sea is creating difficulties for large vessels approaching the shore, and regular dredging operations are required to address the problem. This, in turn, requires additional financial and technical resources.

“It is important to study the consequences of changes in the Caspian Sea level in a broader and more systematic manner. Scientists from various countries around the world are currently studying the dynamics of the decline in the Caspian Sea level, its causes, and the consequences it may have in the future.

“The main issue is not the preparation of a map. With modern scientific and technological capabilities, it is possible to map changes along the Caspian coastline using satellite imagery. The key issue is to determine the actual impact of these changes on the country’s infrastructure, environment, maritime shipping, and offshore hydrocarbon fields. Our research is focused precisely on these areas.”

He added that determining how the Caspian Sea level may change over the next 10–20 years and assessing the potential consequences in advance are of great importance from both scientific and practical perspectives.