Geology and El Niño in the desert:

Understanding windstorms that may follow El Niño storms

"Sandstorms" are one of the more evocative portraits of destructive desert processes. Powerful wind storms can blow dust and sand many miles, moving sand dunes across roads and making the air difficult to breathe. Most sand and dust is blown from a limited number of sites

• Sand blows from places where rivers deposit new sand deposits or where older deposits are disturbed by removing vegetation
• Dust blows from dry lake beds and disturbed sites.

El Niño storms may cause heightened river activity, which would create new sand deposits where the rivers die out in 'sinks'. One such site is at the east end of Afton Canyon, at the Mojave River sinks. USGS and Desert Research Institute plan to place meteorological monitoring stations and dust traps near this sink to study the effects of new river

links:

Understanding desert dust: Where does it come from and where does it go?

Desert geology and resources: On line USGS descriptive pamphlet with lots of information on sand dunes

For further information, contact David Miller

http://geology.wr.usgs.gov/wgmt/elnino/deserten/eolian.html, 30 November 1999, Contact: El Niño Web Team