Environment of Azerbaijan
The Caspian Sea is the largest lake on Earth by both area and volume, with a surface area of 371,000 square kilometres (143,244 mi²) and a volume of 78,200 cubic kilometres (18,761 mi³). It is a landlocked endorheic body of water and lies between Asia and Europe. It has a maximum depth of about . It is called a sea because when the Romans discovered it they tasted the water and found it to be salty. It has a salinity of approximately 1.2 percent, about a third the salinity of sea water.
Caspian lowland desert
The ecoregion is approximately contained within the Caspian Depression, and sunken geological region feeding in to the Caspian, the surface of which is itself at below worldwide sea level. The northern section is almost 900 km wide, and stretches up to 300 km inland across Russia and Kazakhstan. The sector along the southeast coast of the Caspian is mostly in Turkmenistan. Elevations throughout the ecoregion range between -28 and +100 meters. The dry areas were once underwater, but as the sea has slowly receded the dry areas have revealed a landscape of sand dunes, ridges, salt domes, salt pans ('shors'), and clay deserts ('takyrs'). 
The climate of the ecoregion is represented by that in the Volga delta, in the Astrakhan Nature Reserve, where the climate is cool semi-arid (Köppen climate classification BSk). This climate is characterized by high variation in temperature, both daily and seasonally; with low precipitation. Average annual precipitation in the Caspian lowlands is 198 mm. Average temperature in January is , and in July is