Seen from space: Schuchertdal dust storm, East Greenland

This is really very unusual -- on Sept 29th 2018,  NASA staff picked up this strange phenomenon on satellite imagery -- a gigantic dust-storm in East Greenland, caused by very strong north-westerly winds blowing across the dry and dusty sediments of the lower Schuchert Valley.  You can see that some dust is also blowing across the Landtungen peninsula  from the extensive delta at the mouth of Gurreholmsdal.

The Schuchert Valley holds what is probably the biggest sandur in Greenland, fed by the meltwater streams from no less than seven glaciers.  When we were in this area in 1962 it was so ferocious that it was uncrossable in its lower reaches- even at night when flow rates were somewhat reduced.

There is a vast expanse of exposed sands and gravels in the area, and the braided streams that deposit them are so mobile that vegetation has no chance of establishing itself.  And the climate can get very hot and dry during the summer and autumn -- this is the only place where I have ever experienced heatstroke........



The wider context.  This is what the satellite imagery normally looks like in late summer.....



Schuchert Flod sandur -- here the sandur is about 4 km wide.  It's incredibly difficult and dangerous to cross.  In the summer there are so many channels with waist-deep cloudy water (with boulders rolling on the bed) that ropes and back-up are essential.  You may get across some channels, but once you are out in the middle, you are very vulnerable -- water levels can rise very quickly with unexpected melt events upstream -- and if you are exhausted and stranded on  a "dry patch" this is not a good place to be.  One of our expedition members was knocked off his feet and carried downstream for almost 100m before he could be rescued.



Schuchert Flod sandur (low-level aerial photo of a very small area) with considerable meltwater flow in the main channels.