Global environmental problems and the Caspian

In November 2024 Baku hosted the UN climate conference COP29. In those same years, people living on the Caspian coast could see with their own eyes that the sea was retreating. Environmental problems are global, but everyone feels their effects in their own town.

Climate change

Greenhouse gases in the atmosphere (carbon dioxide, methane, water vapour) trap part of the heat leaving the Earth. As we burn coal, oil and gas and cut down forests, CO₂ builds up: before the industrial era its level was about 280 ppm (parts per million), and now it is over 420 ppm. As a result the Earth is warming: according to the World Meteorological Organization, 2024 was the warmest year on record — about 1.55 °C warmer than the average of the late 19th century. The 2015 Paris Agreement aims to keep warming well below 2 °C and to try to limit it to 1.5 °C.

The effects of warming can already be seen: since 1901 sea level has risen by about 20 cm, mountain glaciers are melting, and heatwaves, droughts and downpours are becoming more frequent. There are two ways to respond: mitigation — cutting greenhouse gas emissions (renewable energy, saving energy) — and adaptation — preparing for the changing climate (sea walls, drought-resistant crops).

Forests, deserts and water

Forests cover about a third of the land. In recent years about 10 million hectares of forest have been cleared worldwide each year — more than the area of Azerbaijan. The main cause is turning forest into pasture and cropland (cattle, soy, palm oil); the biggest losses are in the Amazon, the Congo Basin and Southeast Asia. Because of new planting and natural regrowth, the net loss is smaller.

Desertification is the loss of soil productivity in dry lands. Its causes are overgrazing, poor irrigation (which makes soils salty), clearing trees and bushes, and droughts. In the Kura-Araz Lowland, too, part of the irrigated land suffers from salinisation. In Africa's Sahel belt, land has been restored since 2007 through the Great Green Wall initiative. The Aral Sea is the saddest example: it was once the fourth-largest lake in the world, but from the 1960s the Amu Darya and Syr Darya rivers were diverted to irrigate cotton fields, and the sea lost most of its water and split into several parts.

About 2 billion people in the world live without safely managed drinking water. Agriculture accounts for about 70% of freshwater withdrawals, so efficient irrigation (such as drip irrigation) is essential. Pollution is another serious problem: the World Health Organization estimates that air pollution is linked to about 7 million premature deaths every year, and plastic waste collects in rivers and oceans.

The level of the Caspian Sea

The Caspian is a closed basin with no link to the ocean, so its level depends on its water balance: when more water arrives from rivers and precipitation than leaves by evaporation, the level rises; when less arrives, it falls. About 80% of the river water comes from the Volga. In the 20th century the level fell by about 3 m between 1929 and 1977, then rose by about 2.5 m until 1995. Since the mid-1990s it has been falling again — by about 2 m in total, and especially fast in the 2020s. Scientists explain this mainly by the warming climate (more evaporation) and by less water arriving from rivers, above all the Volga.

The falling level is a problem for ports and shipping (channels must be dredged), for sturgeon spawning grounds and for the endangered Caspian seal, which lives nowhere else. Human interference can be risky too: in 1980 the Kara-Bogaz-Gol bay was cut off by a dam to “save” water; the bay almost dried up, and the dam was removed in 1992.