Description

Kalima (or Calima) is a weather phenomena characterised by a suspension of dust or sand particles in the air, typically originating from the Sahara Desert. It is a hot, dry, and hazy wind that blows from the south or southeast, often reaching the Canary Islands.

Dust storms carrying dust across the Atlantic Ocean from the Sahara, as seen from space February 2001. [Source: Wikicommons. Author: NASA/Goddard Space Flight Center.]

Causes

Extreme diurnal heating leads to instability in the lowest level of the atmosphere over the Sahara, warming and drying the air near the surface and cooling while humidifying the air near the top of the layer through convective mixing. Kalima occurs when strong winds, associated with the high pressure system over the Sahara, transport dust and sand across the Atlantic.