Geoscience Reference
In-Depth Information
Chapter 1
Introduction
Peter Knippertz and Jan-Berend W. Stuut
Abstract
Mineral dust is a key player in the Earth system with important impacts
on the global energy and carbon cycles, acting on timescales of minutes to millennia.
Megatons of dust are lifted each year into the atmosphere by strong near-surface
winds over the world's arid regions. Such winds can be generated by short-lived
small-scale dust devils, cold outflow from thunderstorms up to continental-scale
dust storms. The tiny dust particles can be lifted to great heights and transported
thousands of kilometres across the globe. Once airborne, dust affects radiation
and clouds and thereby also precipitation. Dust also alters chemical processes
in the atmosphere and deteriorates air quality and visibility for aviation. Dust is
removed from the atmosphere by gravitational settling, turbulence or precipitation.
Deposition on plants, snow and ice changes the amount of reflected solar radiation.
Iron and other nutrients contained in dust fertilise both terrestrial and marine ecosys-
tems. Dust deposits in glaciers, soils and ocean or lake sediments constitute an
important archive of past environmental changes. For the first time, this topic gives a
detailed account of the state of the art in the fascinating, highly interdisciplinary and
dynamically evolving area of dust research including results from field campaigns,
