Mysterious Dust Transport over the Atlantic Ocean

Staub_Atlantik_gr NASA Earth Observatory
Dust from the Sahara (bottom) is frequently blown towards America (top). The long-range transport of coarse dust has been underestimated so far. (Image: NASA Earth Observatory)

Where do „giant“ dust particles over the remote ocean come from? Buoys have now detected them over water thousands of kilometres away from the west coast of Africa. With up to half a millimeter in diameter, these particles have been regarded as too large and heavy to stay in the air for so long. Scientists from KIT's Institute of Meteorology and Climate Research and the Royal Netherlands Institute for Sea Research are investigating this mysterious observation. So far, these particles have not been considered in climate models – comprehensive computer programs that estimate future development of the climate under certain conditions. Is this justified? We have evidence now that giant particles are in fact transported far away from the Sahara and influence the radiation budget of the atmosphere, clouds and the oceanic carbon cycle. In the new paper in Science Advances the researchers discuss possible explanations through turbulence, transport in thunderstorms and lifting in electric fields. Yet open questions remain that need to be addressed now to minimize model uncertainties.

Further information:
“The mysterious long-range transport of giant mineral dust particles”, Michèlle van der Does, Peter Knippertz, Philipp Zschenderlein, R. Giles Harrison, Jan-Berend W. Stuut.

[Working group: Atmospheric Dynamics]