Why in the news?

• A rare burst of winter rains has triggered the “desierto florido” phenomenon in Chile’s Atacama Desert, turning one of Earth’s driest landscapes into sweeping carpets of fuchsia wildflowers visible from space.

Atacama Desert

• Location:
  • Lies along the Pacific coast of South America, mainly in northern Chile.
  • Extends into southern Peru.
  • Lies between the Andes Mountains (east) and Chilean Coast Range (west).
• Causes of Formation:
  • Cold Humboldt (Peru) Current: Flows northward along the coast, cooling the air and preventing evaporation → leads to temperature inversion and suppressed rainfall.
  • Rain Shadow Effect of the Andes: Moist air from the Amazon Basin rises and cools over the Andes, resulting in precipitation on the eastern slopes, while dry descending air is left on the western side (Atacama).
  • Subtropical High Pressure Belt (STHP): The descending limb of the Hadley Cell (~30°S) creates stable, dry atmospheric conditions.
  • Cold Offshore Winds & Inversion Layer: Prevent upward convection, causing fog (“camanchaca”) but no rainfall.