The Caspian Sea is shrinking. Here’s why

Next week, when world leaders gather in the Azerbaijani capital, Baku, for the 2024 UN Climate Change Conference (COP29), they’ll find themselves next door to an ecological disaster in the making.

Baku lies on the shores of the Caspian Sea, which, despite its name, is actually an inland water body often described as the world’s largest lake – for now.

The Caspian Sea is shrinking due to many of the same issues facing the entire planet: the climate crisis, excessive water use for agriculture, and pollution from nuclear waste, industry and poor urban planning.

But in the case of the Caspian, solutions are hard to come by.

While it has a history dating back millennia of rising and falling, it’s currently about 29 meters below sea level and falling steadily by 7 centimeters each year.

Satellite imagery over the years has shown an alarming growth of arid land in bays and along coastlines of the five countries that surround it: Russia, Azerbaijan, Iran, Turkmenistan and Kazakhstan.

That situation will only get worse – especially if fate of the nearby Aral Sea is anything to go by.

According to two studies published in 2020 and 2021, Caspian water levels are set to fall by nine to 18 meters by the end of the century.

The 2020 study also raise concerns around the potential degradation of coastal ecosystems and wetlands that are currently protected, as well as the impact of pollutants and surplus nutrients from the rivers that feed into the Caspian.

These could create dead zones similar to those found in the world’s oceans, which could affect biodiversity hotspots in both shallow and deeper parts of the lake.

“As the livelihoods and food security of millions of people depend on the Caspian Sea, a loss of these ecosystem services will have drastic socioeconomic consequences and may trigger local and regional conflicts – in an ethnically diverse region that is already rife with tensions,” the paper states.

Why is the Caspian Sea shrinking?

The climate crisis, mainly. Higher temperatures means more water is lost in evaporation than is being replenished through precipitation, which varies from 75 to 1,200 millimeters, depending on the region.

Ironically, the Caspian basin also sits on significant oil and natural gas deposits.

These fossil fuels may be an important source of income for countries like Azerbaijan, Turkmenistan and Kazakhstan, but the greenhouse gases they emit are only exacerbating the lake’s troubles.

The other culprit is reduced flow from the rivers that feed into the Caspian. Russia’s Volga River provides 80 percent of the water entering the lake, but its dozens of dams and reservoirs are siphoning off more water than is sustainable for hydroelectric power and agricultural irrigation.

And yet, Russia is continuing to build dams on the Volga, with 18 still under development, according to Vali Kaleji, an expert on Central Asia and Caucasian Studies at the University of Tehran, in a recent report by CNN.

Western sanctions, he writes in an article, have drastically reduced Russia’s food imports, forcing it to instead grow more food – and thus use more water – in the region.

In fact, discharge along the many rivers in the Caspian Sea catchment area is regulated by 14,000 dams “built for agricultural irrigation, domestic, and industrial purposes over the last 90 years,” says the 2021 study.

The water that does make it into the basin is heavily polluted with sewage and nutrients from agriculture.

People and planet pay the price

Local communities living along the basin’s coastline are facing the impacts of a slowly shrinking lake, says Azamat Sarsenbayev, an environmental activist from the port city of Aktau in southwestern Kazakhstan.

Life in the region, known as Mangystau, “is directly related to the Caspian Sea,” he says.

“The city of Aktau provides villages with drinking water through desalination plants, and the region even receives electricity using water from the Sea, which cools the turbines of power plants.”

On the shore where people used to swim just 10 years ago, a once picturesque seafront has been degraded to a stony desert – and with it, draining precious tourist dollars from the local economy.

The pollution and desiccation of the Caspian is also having an impact on its unique wildlife.

The Caspian seal, for example, is an endemic species whose numbers have plummeted as their essential birthing icefields in the shallow northeastern portion of the lake disappear.

In 2020, aerial surveys by Kazakhstan’s Institute of Hydrobiology and Ecology found a complete absence of seals at one haul-out site, where 25,000 had been counted a decade earlier.

Two years later, alarm bells went off when 2,500 dead seals washed up in Dagestan in Russia’s North Caucasus.

While Russian authorities claimed the seals had died of natural causes, Kazakhstani investigators later concluded that they had likely died of pneumonia caused by pollution.

And just in the past week, at least 289 more seal carcasses have been found on the Caspian shore of southwestern Kazakhstan.

The Caspian seal is now classified as endangered on the International Union for Conservation of Nature (IUCN) Red List. Six species of sturgeon inhabiting the lake, particularly Beluga sturgeon, and Caspian salmon are also on the list.

Can the Caspian Sea be saved?

Unfortunately, there haven’t been any efforts to restore flow to the Caspian, according to Matthias Prange, an Earth systems modeler at the University of Bremen in Germany and lead author of the 2020 paper.

“On the contrary,” he points out. “There are plans from Iran to take more water from the Caspian Sea, desalinate it and use it for households and agriculture in the arid hinterland.”

Sarsenbayev points out that Kazakhstan has created its first-ever research institute for the Caspian Sea, which he says will reduce the country’s reliance on Russian scientists.

“This will allow our specialists to draw their conclusions about the state of the Sea,” he says.

But like many of its neighbors, Kazakhstan is also a major producer of fossil fuels and the world’s ninth-largest coal producer. It recently announced plans to increase oil production by 17 percent by 2029.

Over in Azerbaijan, the U.K.-based Blue Marine Foundation teamed up with a local environmental group and successfully had a marine protected area (MPA) designated near the mouth of the Kura River, a tributary of the Caspian Sea, in 2018.

This MPA includes a country-wide ban on gill-nets in rivers, which should reduce poaching and the accidental by-catch of migratory fish.

Anti-poaching teams also patrol the delta waters, equipped with boats, equipment and even guns, says Rory Moore, head of conservation at the Foundation. “They mean business,” he says.

So far, however, the measures have yet to result in a rise in sturgeon populations, he concedes.

“Sturgeon take a very long time to come back,” Moore explains, “so from the moment you are reintroducing them back into the sea, it might take 12 years for them to reach maturity and come back to the rivers.”

With conservation work on the sturgeon having begun only about five years ago, he says, “we might not see the results for another four or five years.”

So, will hosting COP29 make a difference to the plight of the Caspian?

For Moore, it does present an opportunity “as a fundraising and awareness-raising platform to get some money for conservation into the region.”

But even as it gears up to host the biggest climate event of 2024, Azerbaijan is set to ramp up fossil fuel production over the next decade.

“The Azerbaijanis can see the Caspian retreat before their eyes,” says Frank Wesselingh, a geosciences researcher at Utrecht University and co-author of the 2020 paper.

“I hope it will help to build the appreciation of climate impact in society, but I have not seen real promising signs so far.”