As a child, Iranian environmental journalist Maryam spent most of her time on the shores of the Caspian Sea. From her coastal home in the northern city of Rudsar, she observed how water levels would fluctuate, so much so that in the 1990s, flooding along parts of Iran’s northern coastline left some of her relatives homeless.
All this shape-shifting seemed normal, yet on a recent visit to the area after years away, the body of water was suddenly very unfamiliar.
“I kept walking past the shore, but the water only reached my knees,” said Mariam, whose real name DW chose not to reveal for security reasons. “For someone who grew up on this beach, it was terrifying.”
What he experienced on that trip was nothing unusual. The Caspian Sea, the world’s largest inland body of water bounded by Iran, Russia, Azerbaijan, Turkmenistan and Kazakhstan, is shrinking rapidly.
Although the salinity of the Caspian Sea has fluctuated in the past, scientists say the current decline in water levels, which began in the 1990s, is unlikely to be reversed. Predictions point to even greater retreat this century, with some models indicating a potential decline of up to 21 meters (about 70 feet).
“To put it in perspective, for example, a fall of 18 meters would be greater than the height of a six-storey building,” said Simon Goodman, an evolutionary biologist at the University of Leeds, UK. “That level of degradation would have significant impacts on ecosystems as well as human health, well-being and economic activity.”
Why is the Caspian Sea receding?
Several factors are motivating the retreat. Many rivers flow into the Caspian, but about 80% of its fresh water comes from the north into Russia via the Volga. For decades, the amount of water coming has been affected by dams, irrigation and other forms of water management — particularly in the Volga River basin — but Goodman said the situation ahead is more complex.
“Projections for the rest of this century suggest that the climate change component of ongoing declines will be much stronger,” he said.
Rising global temperatures linked to planet-warming emissions from the burning of oil, gas and coal are increasing evaporation from ocean surfaces. With low levels of precipitation and runoff in the Volga basin, more water is leaving the Caspian than is entering it.
Fish stocks decline, port blocked
And Goodman said, that’s a problem. “The impacts will apply to the entire Caspian Sea,” he said, adding that some are already visible. This is especially true in the northern region of the vast lake bordering Russia and Kazakhstan.
“Many ports around the Caspian require significant dredging to maintain shipping access,” he said, adding that such issues are “likely to intensify within the next five to 10 years.”
The fishing community is also under pressure. Goodman pointed out that in the shallow northern basin, continued declines could make fishing increasingly unviable. And if the level drops by 10 meters, large parts of the northern basin could dry up completely, losing about a third of the ocean’s surface area.
This process is already underway in some places. A spot in the northeastern Caspian, once used by thousands of seals to molt in the spring, is now dry land. “We are already losing ecologically important habitat due to sea level decline,” Goodman said.
Its impact is also visible on the Iranian coastline in the south. With wetlands under pressure, fish stocks have declined and the markets that Mariam remembers were large and vibrant are now a shadow of their former self. And he has seen other undeniable changes.
“The coastline we saw as children is very different from what we see today,” he said. He said a café that once stood at the water’s edge now extended several meters inland.
Could the Caspian be facing an Aral-style crisis?
Goodman said there are already early signs of the Caspian moving toward the Aral Sea, about 1,000 kilometers (600 miles) east.
Once one of the world’s largest inland water bodies – located between Kazakhstan and Uzbekistan – the watershed has largely dried up. In addition to destroying livelihoods and ecosystems, the disappearing lake has had serious consequences for human health, including toxic dust storms.
“We’re already at the beginning of that process,” Goodman said.
If the Northern Caspian dried up, the consequences would go far beyond water loss. Large areas of exposed ocean floor can alter regional climate and release significant amounts of dust into the air, some of which may contain pollutants.
Policy action is not in line with environmental change
Because the Caspian spans five countries, meaningful management will require coordination.
Goodman said that although “governments seem to be beginning to develop collaborative frameworks,” it is still in the early stages.
He said long-term adaptation will require continued investment in scientific research and strategies that address both ecological and economic dimensions. And it should happen quickly.
“The pace of policy must match the pace of environmental change,” Goodman said.
Edited by: Tamsin Walker