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Identify Dust Sources - Past, Present, Future

Many past and existing dust sources are already well known for the Southwest U.S., including dry lake (playa) surfaces and their margins, ephemeral drainage areas, poorly vegetated alluvial fans, agricultural fields, military bases, and growing urban and rural areas.

But there is still much to learn from each kind of setting about antecedent conditions for dust emission, production and availability of fine-grained sediment, dust compositions and pathogen contents, absolute and relative contributions to dust flux, and transport paths from different sources that depend in part on sediment characteristics and surrounding landscape.

We are examining how modern processes in playas and alluvial drainages might influence the generation of dust. Are dust emissions related to large runoff events? Does the frequency of dust events from certain types of sources link to the frequency of desert thunderstorms or seasonal storms? Can runoff events be used as a parameter to help predict future dust storms? Alluvial and hydrologic data from selected playas in the Mojave Desert will be integrated with the monitoring of dust events to address these questions.

We are identifying sources that are active during large regional windstorms using satellite images as well as aircraft-mounted digital cameras and ground-based observations. A current focus is to understand dust production from playa (dry lake) surfaces.

Another activity, launched in 2006, is the development of The Inventory of North American Dust Sources, a database of dust sources based on observed dust events and storms to be used by the community of dust researchers to further understanding dust emission from American drylands.