Introduction - Mineral Dust: A Key Player in the Earth System - page 9

This evolution was a strong motivation to compile this topic, which aims to give a
detailed account of the state of the art in the highly interdisciplinary and dynamically
evolving area of dust research. This topic is meant to allow researchers working
directly on mineral dust and closely related topics to quickly obtain an overview
of the full range of roles that dust plays in the Earth system. It is mainly aimed
at an expert audience (postgraduate to senior researcher level). Parts of this topic,
however, could also be used for specialised teaching activities, such as summer
schools, training courses for operational forecasters in regions prone to dust storms
or modules specialising on aerosol science or climate reconstructions. This topic
covers aspects of dust research reaching from timescales of minutes (e.g. dust devils,
cloud processes, radiation) to millennia (e.g. loess formation, dust in subaquatic
sediment archives) including theoretical concepts, observations and results from
computer modelling and operational forecasts.
Given the breadth and quick evolution of dust research, it would have been
challenging for a single author or a small team of authors to cover enough ground
for an exhaustive treatment of the topic, making it almost unavoidable that this
volume has become an edited topic. This approach has the clear and important
advantage of allowing the direct involvement of a larger number of leading experts
of dust research to cover specific aspects in much detail. The most significant
disadvantage is that of a greater variety in style, depth and approach between the
individual chapters. Naturally, some chapters are therefore closer to full-blown
scientific reviews and others more similar to classical textbook writings. However,
the editors have worked closely with the authors to reduce overlap between chapters,
improve the overall narrative and to remove inconsistencies in terms of terminology
and mathematical symbols used, but some such instances may have remained. It
is hoped that the increase of scientific rigour and breadth brought about by the
approach of an edited topic far outweighs such minor flaws.
This topic is structured into four main parts: Part I: Characteristics of natural
dust particles (Chaps. 2 , 3 , 4 ) details the chemical and physical properties of dust
and how those can evolve from the sources through processing in the atmosphere.
In Chap. 2 , Dirk Scheuvens and Konrad Kandler give a detailed account of the
mineral and chemical composition of natural dust together with information on
typical shapes and size distributions, thereby providing a foundation for subsequent
chapters. The following chapter by Daniel Muhs et al. provides information on
geographical and geomorphological aspects of global dust sources in current times,
but also describes situations in past climates. The discussion of the mineralogical
characteristics of sources provides a direct link to Chap. 2 . The specification
of source areas and their characteristics is a great challenge for the numerical
modelling of dust emission as discussed in Chap. 9 . Finally, Chap. 4 by Alex
Baker et al. reports about how the freshly emitted dust particles, as discussed in
Chaps. 2 and 3 , can be processed in the atmosphere, for example, through chemical
reactions with other aerosol particles or liquids or through physical processes in
clouds. These changes cause a so-called ageing of dust particles, creating coatings
with, for example, sulphate and nitrate or aggregation of particles.