Why northern cities are far more polluted than southern cities?
Geography is one of the reasons for northern cities being far more polluted than southern. Cities like Delhi, Varanasi lie within Indo-Gangetic Plain, a region landlocked and boxed in by Himalayas. This bowl-shaped terrain traps pollutants, preventing them from dispersing. The situation worsens in winter due to weather phenomenon called winter inversion where denser air settles near ground.