Dust storms generally call to mind places like the Sahara Desert or the Gobi Desert, but dust storms occur at high latitudes as well. One such storm left streamers over the Gulf of Alaska in mid-November 2010.
The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite captured this natural-color image on November 17, 2010. Thin plumes of beige dust blow off the Alaskan coast toward the south-southwest. Farther to the south, lines of clouds mimic the shape and direction of the dust plumes, and even cast shadows on them. The dust plumes and clouds were likely shaped by the same winds.
Malaspina is just one of many glaciers fringing the Alaskan coastline. As glaciers grind over rocks, they pulverize some of the rock into glacial flour. Melt water percolating through glaciers often deposits glacial flour in mud plains. When the plains dry out, winds sometimes carry dust particles aloft.
Articolo di Nasa Earth Observatory del 19 novembre 2010
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