Dust off the Coast of Western Africa

(Click on image for larger view.)

A massive plume of thick dust blew off the west coast of Africa on April 29, 2012, as the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite captured this natural-color image. Dust extended from Mali to Cape Verde. Aside from some cloudbanks, skies over western Mauritania were relatively clear.

Sand seas sprawl over large parts of Mauritania and Mali, and provide plentiful material for dust storms. Unusually dry conditions in Mali might have worsened the potential for dust storms by drying marsh sediments. Mali experiences a three-month rainy season from June to August. On April 13, 2012, the United Nations reported that the 2011 rainy season only brought rain for one month, setting the stage for drought the following year.

In this image, a band of pale color appears southeast of the dust plume off the Senegal coast. This is not dust but sunglint—the reflection of sunlight off the ocean surface and into the satellite sensor.

References:
United Nations Integrated Regional Information Networks. (2012, April 13) Mali: Beyond the drought – “Families will disappear.” AllAfrica.com. Accessed May 1, 2012.
NASA image by Jeff Schmaltz, LANCE MODIS Rapid Response. Caption by Michon Scott.

Instrument:
Terra - MODIS - NASA