Why the Caspian Depression Is Arid

The Caspian Depression (between Caucasus and Urals) is arid due to:

• Rain shadow – Caucasus Mountains block moisture from Black Sea.
• Continental interior – Far from oceans, limited moisture inflow.
• Distance from tropics – Isolated from primary humidity sources.
• Subsiding air – Atmospheric circulation causes drying, warming descent.

Annual precipitation <250 mm; high evaporation creates salt flats and deserts (Karakum, Kyzylkum).