Caspian Region: preventing the impending environmental disaster

Over the preceding decades, the Caspian Sea (the biggest landlocked water body on our planet) faced a series of environmental problems, and human economic activities constitute the major contributing factor, in particular, it is contamination in the course of exploration/production/transportation of hydrocarbons, industrial waste exposure, and discharge of untreated household effluents, etc. Along with the concerns about steady decline of the environmental health of this unique natural site, the academic community is seriously concerned with the on-going lowering of the Caspian Sea water level bearing additional risks both for the marine ecosystem and for the economies of the Caspian countries. Experts and academia from Russia, Azerbaijan, Kazakhstan, Iran and Turkmenistan will be discussing the shallowing of the Caspian Sea and other related issues at the forthcoming 29^th conference of parties of the UN Framework Convention on Climate Change (ÑÎÐ29) in Baku.

Zone of peace, neighborliness and cooperation

In the last century, the Caspian Sea, which geographers often call  «the biggest lake on Earth» was practically the internal sea of the Soviet Union – only 13.8% of it belonged to Iran. Then, the USSR and Iran defined the legal status of the Caspian Sea with the agreements signed in Leningrad and Rasht, as well as Gulistan and Turkmenchay Treaties, the Soviet-Iranian Treaty of Friendship and the Treaty of Commerce and Navigation. After disintegration of the Soviet Union, new international law entities appeared on the global political map: the Russian Federation, Azerbaijan, Turkmenistan and Kazakhstan leading to the need for developing the new legal status of the Caspian Sea.

Eventually, «the Caspian Five» spent 20 years negotiating to achieve the consensus about using this unique water body. On 12 August 2018, in the course of the 5^th Caspian Forum in Aktau five coastal countries signed the Convention on the Legal Status of the Caspian Sea. This became an important historical milestone, because being an inland water body without a natural exit to the World Ocean the Caspian Sea is not regulated by international Law of the Sea conventions.

The Convention on the Legal Status of the Caspian Sea defines the priorities for cooperation in various spheres of the coastal activities and is designed to assure maintaining the integrity and sustainable development of the Caspian Region. Its main principle is the use of the Caspian Sea for peaceful purposes turning it into the zone of peace, neighborliness, friendship and cooperation.

The Caspian Basin is the important strategic region with colossal economic, energy and transportation potential.

Huge oil and gas reserves are concentrated here. The hydrocarbon reserves of the Caspian Sea are estimated at the level of 18 bn tons of reference fuel, the proven reserves – up to 4 bn tons. This is the second position after the Persian Gulf [1].

The Caspian Region has big geo-strategic value as it plays the role of important transit/transportation/logistical hub in the Eurasian area. Currently, this region is key for such multimodal international transportation corridors (ITCs) as North-South and East-West.

Due to its isolation from the World Ocean, the Caspian Sea features special climatic conditions and salinity gradients, a unique ecosystem was formed here in the course of many millions of years. Natural resources of the Caspian Region include over 500 species of plants and 854 species of fish, of which about 30 species are of commercial value: beluga sturgeon, starred sturgeon (sevruga), sterlet sturgeon, common sturgeon (circa 90% of global sturgeon reserves), pike perch, etc. Overall, about 400 species are endemics. As of today, many species of the Caspian Sea are endangered due to excessive use, deterioration of their habitats, contamination and climate change. In the Northern part of the Caspian Sea the shallow waters abound with shell-fish, crustaceans, fish and birds. Seals are feeding their babies on the winter ice normally emerging only in this section of the water body. And all of them are dependent on the normal level of water [2].

However, the problem is in dramatic shallowing of the Caspian Sea during the recent 20 years. The situation in the Russian and Kazakhstan sectors of the Caspian Sea (the Northern part) is especially critical. The Russian academic community gives raise to alarm noticing that over the recent couple of decades the sea surface decreased by more than 23 thou sq. m. According to the Institute of Water Problems with the Russian Academy of Sciences (RAS), if the current situation persists, the Northern part of the Caspian Sea will disappear. According to the Ministry of Environment and Natural Resources of Kazakhstan, starting from 2006, the sea surface decreased by more than 31 thou sq. m. In Magistau Region of Kazakhstan, in the summer of 2023, the local emergency situation was announced due to dramatic shallowing of the Caspian Sea. For Kazakhstan, the Caspian Sea is an important source of potable water. The only desalination plant in the country is based on the coast by the Aktau port, it processes 25 thou cubic meters of saline water per day.

Natural «breath» of the Caspian Sea

The first scientific observations of the Caspian Sea level fluctuations started in 1837. Since then, there were three dramatic changes of the sea level. Between 1837 and 1930, the level dropped approximately by 1 meter, between 1930 and 1977 – by 3 meters, and between 1978 and 1995 it raised by 2.5 meters. Then the sea again started its dereliction. According to Vasily Sokolov, the Deputy Head of the Federal Agency for Fishery, since mid-1990s the Caspian Sea level dropped by more than 2 meters.

According to Meteo Journal, only since 2011, the level of the Caspian Sea dropped by 1.74 meters. And this decline was especially dramatic during the recent three years. In 2021, by 20 cm, in 2022 – by 27 cm, and by 29 cm in 2023 [3].

Specialist said that such a significant and dramatic shallowing of the Caspian Sea can be viewed as a critical situation, especially if in future this process maintains its intensity. In 2017, the academic journal Geophysical Research Letters wrote that Russia may lose its section of the Caspian Sea in 75 years already: the aquatic area will simply wither away. The group of authors of this publication from the USA, Russia and Azerbaijan linked this pessimistic forecast with the current pace of the global warming. There are also serious concerns in Kazakhstan about the Caspian Sea can follow the way of the Aral Sea, which withered away completely practically in front of our eyes.

At the same time, there are experts who do not see any reasons to believe that the Caspian Sea will disappear. They say, that the sea is subject to periodic multi-year annual and seasonal fluctuations because it is a landlocked water basin. Several thousand years ago, the level of the Caspian Sea could be different from the current level by ten and more meters. Scientists call it a natural process, the so-called «Caspian breath», when every 200-300 years water comes back again. Thus, according to the Institute of Geography with the National Academy of Sciences of Azerbaijan, over the last 4,000 years, the Caspian Sea level went down every 250 years, and then went up again over about the same period.

Why is the Caspian Sea shallowing?

Numerous factors different in their nature affect the level of the Caspian Sea. Valery Malinin, Doctor of Geography, professor of the Russian State Hydrometeorological University groups these factors into four big groups: cosmic and geophysical factors, geological and geo-dynamic processes, hydrometeorological processes and anthropogenic factors (human impact) [4].

Given the big variety of factors affecting the Caspian Sea level, many in the academic community believe that shallowing of the biggest landlocked water body on Earth is mainly underpinned by the water balance parameters changing under the influence of the human-induced climate change. The elements of the water balance of the Caspian Sea are in-flowing rivers, the levels of precipitation and evaporation.

For example, during the period between 2006 and 2022, the precipitation in the aquatic area of the Caspian Sea was very low – its amount decreased from 120 down to 42 km³. At the same time, the evaporation grew due to the temperature growth. According to the American Geophysical Union (AGU), starting from 1979, the average temperature at the Caspian Sea surface was growing approximately 1 degree Celsius per annum.

In the opinion of Vladimir Ushivtsev, the leading research associate of the Southern R&D Center of RAS, Candidate of Biological Sciences, shallowing of the Caspian Sea results from decrease of the average annual precipitation in the Volga Basin, which is underpinned by the change of cyclone’s direction. In its turn, such change is caused by global climate change. According to his estimates, 20 years ago cyclones from the Atlantic Ocean always went across the central part of Russia and discharged their waters into the catch basin of the Volga River, flowing from there into the Caspian Sea, which had its own evaporation balance and water input. Now these cyclones have moved to the North and precipitate around Moscow and Saint Petersburg, such feeding the Arctic Ocean [5].

At the same time, we can observe a steady multi-year trend of decreasing the river runoffs to the Caspian Sea. Overall, there are 130 rivers flowing into the Caspian Sea. They include Volga, Urals, Terek, Kura, Darvagchay, Rubas and others. The Volga River is the main waterway accounting for over 80% of the river runoffs to the Caspian Sea. Its drainage basin constitutes 1,360 thou sq. km. Overall, 2,600 rivers flow into the Volga River and its water reservoirs, the main tributaries and the Kama River and the Oka River. Every year, the Volga River brings approximately 250 km³ of water to the Caspian Sea.

Low water levels have been observed in the Volga River over the recent decades. According to Meteo Journal, its discharge in 2021 was 29.9 km³ below the long-time average annual, in 2022 – 25.93 km³ below, and in 2023 –30.43 km³ below.

Experts say that global warming covering the entire Northern Hemisphere is the main reason for such low water level of one of the biggest rivers of Russia. According to Said Safarov, the Head of Section of the Institute of Geography with the National Academy of Sciences of Azerbaijan, the water discharge of the Volga River lost 492.2 km³ over the period from 1977 to 2020 due to the climate change. If we divide this volume by the surface area of the Caspian Sea (371,000 km³), we will get 1.33 meters – exactly the layer of water that the Sea lost due to the climate impact on this river.

In addition to natural factors, human-induced load also contributes to the decrease of the Volga River discharge. It is known that during the Soviet period nine water reservoirs were built on the Volga River: Verkhnevolzhskoye, Ivankovskoye, Uglichskoye, Rybinskoye, Gorkovskaoye, Cheboksarskoye, Saratovskoye, Volgogradskoye, as well as Kuibyshevskoye – one the biggest reservoirs in the world; they are filled with water mainly for irrigation purposes and for water supplies to the adjacent territories.

At the same time, Vladimir Shevchenko, acting Director of the Institute of Oceanology named after P.P. Shirshov, believes that shallowing of the Caspian Sea is associated not only with the cascade of water reservoirs on the Volga River, but with cyclic changes in general, because such dramatic changes of the sea level took place before the reservoirs were built. On the other hand, even when the reservoirs were already in place, the level of the Caspian Sea was growing between 1977 and 1985 [6].

Another factor of the water level drop in the Caspian Sea is the fact that it is adjacent to Kara Bogaz Gol (in Turkic languages «kara» means black, «bogas» – throat/bay, «gol» – lake) in the Western part of Turkmenistan, which is 4.5 below the sea level [7]. Kara Bogaz Gol is a vast shallow lagune connected with the Caspian Sea through a narrow 9-meter channel with 800 m width and 3-4 m depth. Constant flow from the Caspian Sea is observed in the channel with the speed of 50-100 cm/sec. The lagune is a giant evaporator, its surface, water volume and depth may change significantly depending on the water balance and level of the Caspian Sea.

Shallowing aftermath

Shallowing of the Caspian Sea definitely has a huge negative impact on its ecosystem and on the coastal environment. Further decrease of the sea level may turn out to be a real environmental disaster and disappearance of the population of various species of animals and birds. In particular, Caspian seals are currently at risk, and their number is decreasing dramatically. Thus, between 1990 and 2012, their population dropped from 1.2 mln down to 274 thou specimen. Mass mortality of ringed seals is also periodically observed on the Caspian coast.

This is associated with the fact that low precipitation and high evaporation decreased the thickness and seasonal duration of the ice sheet, which is key for the seals’ reproduction. Hence, they are forced to change their usual habitats, which again adversely affects their birth rates. In addition, new habitats may be contaminated by hydrocarbons production leading to accumulation of toxic products in the organisms of marine animals leading to them losing their resistance to diseases and environmental stress.

Russian scientists are concerned with the water level dropping in the Volga River estuary due to shallowing of the Caspian Sea, and hence – to aquatic plants build-up. This will lead to decrease of the flowage of the main river arms, impede fish from reaching the spawning areas and eventually losing these spawning areas completely [8]. Vasily Sokolov, the Deputy Head of the RF Federal Agency for Fishery, believes that if the issue with regulating the Volga River discharge is not resolved in the near future, there will be problems not only with the Caspian seals’ population, but also with meaningful commercial fish resources (such as sprat and anchovy, for example).

About 300 kt of fish are harvested in the Caspian Sea annually making 30% of the total fish harvest in Russian inland water bodies. Sprat/anchovy account for up to 200 kt. In monetary terms, the Caspian fish resources are estimated at USD 6 bn.

According to Vali Kaleji, and Iranian researcher, if the Northern part of the Caspian Sea with its rich fauna withers, it will have serious environmental impact. It may also constitute a threat for the protected territories and wetlands, such as the Volga River estuary, the Horgan Bay (the biggest in the Caspian Sea) the Miankaleh lagune on the South-East coast of Iran. Shallowing and withering of wetlands may lead to formation of dust masses and impact the weather in the coastal areas [9].

The drop of the Caspian Sea level has negative implications for well-being of the local population, for their social and economic lifestyle patterns, as well as on the ecosystems, which are economically important for people. The environmental changes may lead to migration and decrease of population in the coastal cities and villages around the Caspian Sea. As of today, the total population of the areas surrounding the Caspian Sea is 15 mln people.

The drop of the water level is critical for fisheries, and dramatic change of the coastal profile impedes transit and navigation in the Caspian Basin. Shallowing of the Caspian Sea may result in the sea ports’ infrastructure losing its functionality, especially alongside the coasts of Kazakhstan and Russia [10].

For example, the Aktau port in Kazakhstan was totally upgraded in 1999. Since then, the drop of the sea level at the births there was over 2.5 m. It leads to the situation when oil tankers of 12 kt deadweight going to Makhachkala can accept only up to 7 kt (60% of their carrying capacity); the oil tankers of 12 kt deadweight going to Baku can accept only up to 10 kt.

A similar situation is observed in Kuryk port. Starting from 2016, the water level here dropped by almost one meter and a half. The administration started preparatory activities for dredging operations in the port water area and in the approach channel.

Shallowing of the Caspian Sea also impact the operations of the Russian ports in Astrakhan Region. In December 2022, President Vladimir Putin instructed the RF Government to organize dredging operations in the Volga-Caspian Canal to assure optimal lane for vessels with 4.5 m submersion in the context of developing the North-South International Transportation Corridor (ITC) [11]. According to Alexander Karavayev, the CISS expert, the unprecedented number of dredging vessels were engaged – over 28 vessels including barges and 12 dredgers of various types. By the end of 2023, the majority of the objectives was achieved. Navigation improved along with the carrying capacity of ships going to the ports of Astrakhan and Olya. Turkmenistan and Iran did not suffer that much from the Caspian Sea shallowing, and the situation is relatively stable in Azerbaijan.

Discouraging forecasts

Recently, several German and Dutch researchers created a projection model predicting the change of the Caspian Sea level until the end of this century [12]. They claim that starting from 1990s, the Caspian Sea level has been dropping several centimeters annually. They emphasized that the level of such landlocked water bodies as the Caspian Sea is normally defined by the very delicate balance between precipitation and discharge on one hand, and evaporation from the sea surface – on the other. They explain the Caspian case by intense evaporation and loss of seawater ice during the winter period. According to Western researchers, these processes are related with the general increase of the dryness index in the Mediterranean and Central Asian region.

According to the presented forecasts, by 2100 the Caspian Sea level will drop by 9 meters in the best case and by 18 meters in the worst case. On top of that, the sea surface area will decrease by 23-34%. Eventually, the big shelf of the Northern Caspian Sea, the Turkmen shelf in the South-West, as well as all the coastal areas of the middle and Southern Caspian Sea will become the terrestrial land. Kara Bogaz Gol will wither.

In addition to the catastrophic consequences for flora and fauna of the Caspian Sea Basin, all this will have an extremely adverse effect on the everyday life of millions of people, and the region will enter the times of political tension. The «Caspian Five» countries will have to develop and adopt new borders and fishing rights treaties.

However, Chingiz Ismailov, the Doctor of Geography and professor of the Baku State University, is quite skeptical about the forecasts of the European researchers about the Caspian Sea level drop, he believes they are not underpinned by serious facts [13]. In his opinion, the existing projections of the Caspian Sea level fluctuations need to be challenged, as various assumptions are made by specialists not being based on the actual data analysis, and adequate database is required for the long-term forecast of the sea level fluctuations. According to Chingiz Ismailov, those who are sitting at their computers far away from the region and including one or several indicators into their models cannot be making long-term forecasts. The Azerbaijanian researcher believes that Caspian studies should be the competence of scientists from the Caspian countries, because they have access to the database accumulated over many decades and have all the opportunities for field research.

COP29 will be looking for solutions to Caspian problems

The factors of the Caspian Sea shallowing and other environmental problems of this unique natural site will be discussed at the forthcoming global climate summit in Baku. In 2024, in the context of preparations to ÑÎÐ29 Azerbaijan organized a number of events dedicated to environmental problems of the Caspian Sea with participation of prominent scientists and researchers from the Caspian countries and from other regions of the world.

The issue of the Caspian Sea level drop is periodically on the agenda of the «Caspian Five» meetings. Thus, at the 6th Caspian summit in Ashkhabad in June 2022, Ilham Aliyev, the President of Azerbaijan, focused the attention of his colleagues on the dramatic decrease of the Caspian Sea surface area and called for establishing an expert panel comprising the representatives of all the coastal countries to establish the cause-and-effect links of the on-going processes and to develop recommendations on how to change the negative trends. This panel was established and already had two meetings – first in Teheran, and then in Baku.

Presidents of Russia and Azerbaijan Vladimir Putin and Ilham Aliyev discussed the Caspian Sea shallowing during their meeting in Moscow this summer.

Early in October Baku and Moscow announced creating a dedicated thinktank on the Caspian Sea shallowing. It comprised specialists from various R&D centers. Sergey Anoprienko, the Deputy Minister for Natural Resources of the Russian Federation, and his Azerbaijanian colleague Rauf Gadzhiyev were appointed the co-chairs of the group. The thinktank is expected to develop a roadmap including the research of the causes of the Caspian Sea shallowing, short-term and long-term forecasts, monitoring measures and mitigation strategies.

Kazakhstan intends to open a dedicated R&D center before the end of 2024 to focus on environmental problems of the Caspian Sea, including shallowing, causes of mass fish and seals mortality, preservation of the Caspian seals and fish population in the aquatic and coastal areas. This center will operate in close cooperation with its peers from other Caspian countries.

In October 1992, the heads of the Caspian states met in Teheran to discuss the possibility of establishing the Caspian Economic Cooperation Organization. The meeting reviewed the outlook for such structures as Caspian Inter-State Oil Company, Caspian Inter-State Bank for Economic Cooperation, Caspian Development Bank, Center for Caspian Economic and Political Studies, R&D Center for the Caspian Sea bioresources. These initiatives were not implemented, and one of the reasons for that was the unregulated legal status of the Caspian Sea. 

It should be noted that the Caspian countries are undertaking individual and collective efforts to protect and preserve the Caspian Sea. By 2006, Russia, Kazakhstan, Turkmenistan, Azerbaijan and Iran ratified the Framework Convention for Protection of the Marine Environment of the Caspian Sea (the Teheran Convention), which became the first legally binding document signed by all the Caspian countries targeted to assure environmental safety of this unique water body [14].

The Convention is the common basis for defining the key requirements and the institutional mechanism for protecting the marine environment of the Caspian Sea. Specific obligations of the Caspian countries are defined and controlled by the Convention protocols. As of now, the «Caspian Five» adopted four protocols to the Teheran Convention in the following areas, which are of major concern:

• Protocol on Contamination Sources;
• Protocol on Major Oil Spills Response;
• Protocol on Cross-Border Environmental Impact Assessment;
• Protocol on Preservation of Biodiversity.

Some of these protocols are already ratified by all five Caspian countries, and some – by some countries. Currently the Teheran Convention Parties are negotiating the Protocol on Data Monitoring, Assessment and Exchange.

Conclusion

To summarize it is worth noting that the Caspian Sea is critical for each country of the «Caspian Five» – from the standpoint of either bioresources, hydrocarbons reserves and transport communications. Turning this region into the zone of peace, neighborliness and cooperation is in the interests of all of the Parties. All the problems here are similarly important and relevant, and it means that its protection should be the common cause. It is necessary to undertake even more active efforts in finding solutions to cope with the existing challenges in the aquatic and coastal areas of the Caspian Sea, to assure effective measures to prevent the è impending environmental disaster.