Geomorphology of the Chihuahuan Desert based on potential dust emissions

TitleGeomorphology of the Chihuahuan Desert based on potential dust emissions
Publication TypeJournal Article
Year of Publication2011
AuthorsBaddock MC, Gill TE, Bullard JE, Acosta D, Rivera NIRivera
JournalJournal of Maps
Pagination249-259
Accession NumberJRN00566
KeywordsChihuahuan Desert, dust emissions, ephemeral lakes, geomorphology, playas
Abstract

The Chihuahuan Desert of central northern Mexico and southern Arizona, New Mexico and Texas, USA,
is a regionally significant dust ’hot-spot’ in North America. Typical of other such hot-spots, this desert
consists of a mosaic of geomorphological settings, each of which has a varying propensity for dust emission.
Recently, a classification system of dust emission potential based on surface geomorphic characteristics
that establishes a common framework for describing the land surface has been proposed. The
classification is readily applicable to different dust source regions and designed to facilitate comparison
of the relative potential dust contributions and emissivity of varying geomorphological environments in
such regions. The map here (1:3,500,000) was compiled by applying the new classification to a base map of polygons
from existing soil and landform maps that were produced by national government agencies. Within the
study area, 11 of the 17 possible geomorphic classes were present, the most extensive being unarmoured,
unincised high relief alluvial surfaces, which covered 43% of the area. As an example of how empirical dust source point data can be used with the classification, the satelliteobserved
origins of dust plumes for 26 major wind erosion events from 2001 to 2009 were overlain on the
map. Despite a total area of only 4%, ephemeral lakes were the source of 48% of the observed plumes.
This map and the relationships derived from it provide the basis for developing equivalent maps in other
dusty regions, and mark a step toward improving the representation and documentation of the strength
of dust sources in numerical mineral aerosol models.

DOI10.4113/jom.2011.1178