There’s a spot on the shoreline from where Azamat Sarsenbayev used to jump into the brackish, blue-green Caspian Sea. Only a decade later, it now overlooks bare, stony ground stretching toward the horizon.
The water has receded far and fast from the coastal city of Aktau in Kazakhstan, where the eco-activist has lived his whole life. “It is very difficult to watch,” he said.
More than 1,000 miles to the south, near the Iranian city of Rasht, Khashayar Javanmardi is alarmed. The sea here is choked by pollution.
“I cannot swim anymore … the water changed,” said the photographer, who has traveled the Caspian’s southern shore, documenting its decline.
Both men feel intimately connected to the water they grew up alongside. Both are terrified for its future.
Azamat Sarsenbayev
The Caspian Sea is the planet’s largest inland sea and its largest lake, an enormous body of water roughly the size of Montana. Its looping coastline stretches more than 4,000 miles and is shared by five countries: Kazakhstan, Iran, Azerbaijan, Russia and Turkmenistan.
These countries rely on it for fishing, farming, tourism and drinking water, as well as its coveted oil and gas reserves. The Caspian also helps regulate this arid region’s climate, providing rainfall and moisture to Central Asia.
But it’s in trouble.
Damming, over-extraction, pollution and, increasingly, the human-caused climate crisis are driving its decline — with some experts fearing the Caspian Sea is being pushed to the point of no return.
While climate change is raising global sea levels, it’s a different story for landlocked seas and lakes like the Caspian. They rely on a delicate balance between water flowing in from rivers and rainfall and leaving through evaporation. This balance is changing as the world warms, causing many lakes to shrink.
People don’t need to look far to see what the future might hold. The nearby Aral Sea, straddling Kazakhstan and Uzbekistan, was once one of the world’s largest lakes but has all but disappeared, devastated by a combination of human activities and the escalating climate crisis.
An aerial image of the northern part of the Caspian Sea on September 20, 2006
An image of the same location on September 19, 2022. NASA
Over many thousands of years, the Caspian Sea has swung between highs and lows as temperatures fluctuated and ice sheets advanced and retreated. In the past few decades, however, the decline is accelerating.
Human activities play an important role, as countries build reservoirs and dams. The Caspian is fed by 130 rivers, although around 80% of the water comes from just one: the Volga, Europe’s longest river, which winds through central and southern Russia.
Russia has built 40 dams, with 18 more in development, according to Vali Kaleji, an expert on Central Asia and Caucasian Studies at the University of Tehran, reducing the flow of water entering the Caspian Sea.
But climate change is playing an increasingly significant role, increasing evaporation rates and fueling more erratic rainfall.
Caspian Sea water levels have been falling since the mid-1990s, but have sped up since 2005, dropping by about 5 feet, said Matthias Prange, an Earth systems modeler at the University of Bremen in Germany.
As the world warms further, levels are set “to drastically fall,” Prange told CNN. His research predicts declines of 8 to 18 meters (26 to 59 feet) by the end of the century, depending on how quickly the world cuts fossil fuel pollution.
Another study suggests drops of up to 30 meters (98 feet) are possible by 2100. Even under more optimistic global warming scenarios, the shallower, northern part of the Caspian Sea, mostly around Kazakhstan, is set to completely disappear, said Joy Singarayer, a paleoclimatology professor at the University of Reading, and the study’s co-author.
The port city of Aktau, Kazakhstan, located on the Caspian Sea coast on September 1, 2024.
Muhammed Enes Yildirim/Anadolu/Getty Images
The southern coast of the Caspian Sea near Galugah city in Mazandaran province, Iran on November 23, 2020. Water level have dropped significantly over the past decades due to climate change and human activities.
Hossein Beris/Middle East Images/AFP/Getty Images
For Caspian Sea countries, this is a crisis. Fishing grounds would shrink, tourism would decline, and the shipping industry would suffer as vessels struggle to dock in shallow port cities like Aktau, the University of Tehran’s Kaleji said.
There would be geopolitical ramifications too. Five countries competing for diminishing resources could culminate “in a race to extract more water,” Singarayer said. It could also set up new conflicts over oil and gas reserves, if shifting coastlines push countries to make new claims.
The situation is already disastrous for the Caspian Sea’s unique wildlife. It’s home to hundreds of species, including the endangered wild sturgeon, the source of 90% of the world’s caviar.
The sea has been landlocked for at least 2 million years, its extreme isolation resulting in the “emergence of bizarre creatures such as very strange cockles,” explains Wesslingh.
But receding water is depleting oxygen levels in its depths, which “might wipe out the remaining survivors of millions of years of evolution,” it’s “a massive crisis that almost no one knows about.”
A view shows dead Caspian seals washed up on the coast of the Caspian Sea in Makhachkala, Russia, December 6, 2022.
Kazbek Basayev/Reuters
It’s a crisis too for Caspian seals, an endangered marine mammal found nowhere else on Earth. Their pupping sites in the shallower northeastern Caspian Sea are shifting and disappearing, as the animals also struggle against pollution and overfishing.
Aerial surveys show huge reductions of seals, said Assel Baimukanova, a researcher at the Institute of Hydrobiology and Ecology in Kazakhstan.
Scientists counted 25,000 at one haul-out site on the Durnev Islands in the northeast Caspian Sea in 2009. “By the spring of 2020, we did not observe a single individual,” she told CNN.
There are few easy solutions to this crisis. The Caspian Sea is in a region that has experienced a lot of political instability, and is shared between five countries, each of which will experience its decline in different ways.
No one country is to blame, but if they fail to take collective action, there could be a repeat of the Aral Sea disaster, Kaleji said. There is no guarantee the Caspian “will return to a natural and normal cycle,” he added.
Oil rigs on the Caspian Sea in Baku, Azerbaijan on August 8, 2020.
Aziz Karimov/Getty Images
Rising concern about the Caspian’s fate comes at a time of heightened scrutiny on the region.
Next month, global leaders will gather in Azerbaijan’s coastal capital city Baku for COP29, the United Nations’ annual climate summit, where they will discuss climate action in the shadow of the oil rigs dotted across this part of the Caspian Sea.
In August, the country’s President Ilham Aliyev said the Caspian Sea’s decline was “catastrophic” and becoming an ecological disaster — but at the same time the country plans to expand its own production of the fossil fuels that are helping drive it.
Azamat Sarsenbayev
Back in Kazakhstan, Sarsenbayev is trying to draw attention to the Caspian’s plight through beautiful, sweeping footage he posts on Instagram.
If the climate crisis and water over-extraction continue unabated, he fears “the Caspian Sea may face the fate of the Aral Sea.”
In Iran, Javanmardi, continues to photograph the Caspian coastline, documenting the polluted water, shrunken shores and desiccated sea beds, as well revealing the beauty that still exists and the connections people have to the sea.
He wants people to wake up to what’s disappearing.
“This is the biggest lake in the world,” he said, “all people should consider it as something important.”
