Some of the following scenarios are hypothetical in nature but should still be taken with merit as they reflect the possible future events and issues.
Return of the Dust Bowl times?
“The dust storms are a harbinger of a broader phenomenon, researchers say, as global warming translates into less precipitation and a population boom intensifies the activities that are disturbing the dust in the first place. Jayne Belnap, a research ecologist at the U.S. Geological Survey who has studied the issue, predicts that by midcentury, the fragility of the region’s soil “will be equal to that of the Dust Bowl days,”” (Eilperin, 2009).
Global warming could exacerbate the problem
“Under global warming, increased drought is projected for the southwest US, Middle East, and the expanding Sahel. All of these deserts are known dust sources for winter and spring deposition to mountain snow cover in the Rocky Mountains, Central Asia, and the Alps, respectively” (Painter et al., 2007).
“Future drying in desert regions and projected expansion and intensification of use of arid and semi-arid lands could cause regional dust emission to increase in frequency and magnitude. Therefore, earlier snowmelt and its effects on mountain water resources and glacial extent is a likely scenario in many of the world’s mountain ranges under enhanced dust deposition” (Painter et al., 2007).
“By 2050, increased temperature alone is expected to decrease average soil moisture conditions in the southwestern US to levels below those experienced during the most severe droughts of this century, including the Dust Bowl years. Such declines in soil moisture will probably result in a reduction in the protective vegetative cover, a slower recovery from disturbance, and an increase in dust emission from exposed soil. Lower soil moisture will also mean drier fuels that burn more readily – wildfires in the western US are projected to increase substantially in both frequency and intensity, which will also increase exposed soils and the hydrophobicity of those soils, thus amplifying dust emissions” (Field et al., 2009).
Human activity “fueling the fire”
“An increase in human settlement/use of these landscapes will be accompanied by a further loss in the protective covering of plants, plant litter, and physical and biological soil crusts, thereby amplifying dust emissions from the disturbed surfaces. Offroad recreational activity in southern California has risen from virtually zero in 1960 to almost 10 million user-days in 2006. If users drive 32 km per day, this specific activity alone, in this relatively small region, can generate as much as 2.7 metric tons of dust per year. The now-exploding exploration and development of energy resources (including wind and solar) in dryland regions are also of concern. All of these activities will result in the loss of vegetation and soil surface protectors (eg scraping away vegetation for solar farms and oil pads), increased offroad vehicle traffic, pipelines, transmission lines, and greatly increased traffic on existing and newly established dirt roads” (Field et al., 2009).
“In summary, greater dust emissions, including more frequent and larger dust storms, are likely to occur from dryland regions as temperatures increase and more dryland areas are trampled, cleared of vegetation, plowed, and/or converted from perennial to annual plants” (Field et al., 2009).
Hurdles to overcome
“The overarching challenge for ecologists and other environmental scientists, land managers, and policy makers will be to work together to manage vulnerable areas in ways that reduce excess dust production to the fullest extent possible” (Field et al., 2009).
Innovative storm prediction techniques
“Researchers based at the University of Pittsburgh have developed a method for predicting dust and sandstorms that uses infrared satellite images to determine when conditions are ripe for the destructive phenomena, a technique that could be implemented globally and that the research team used to forecast a 2008 New Mexico dust storm — the area’s largest in decades — two days beforehand.
Thermal and visible images of New Mexico’s White Sands Dune Field captured by NASA’s Earth-orbiting ASTER (Advanced Spaceborne Thermal Emission and Reflectance Radiometer) instrument reliably indicated when soil moisture levels were low enough to result in a dust storm, the team recently reported in the Journal of Geophysical Research Earth Surface. Lead author Stephen Scheidt, a research associate in Pitt’s Department of Geology and Planetary Science; Michael Ramsey, a Pitt associate professor of geology and planetary science and member of NASA’s ASTER science team; and Nicholas Lancaster of Nevada’s Desert Research Institute further determined that this approach could be expanded into a worldwide system to monitor areas prone to dust storms or to track drought in regions threatened by desertification” (ScienceDaily, 2010).
Publications to look out for
Painter, T. H., J. Deems, A. Hamlet, J. Belnap, and C. C. Landry, Decreased yield from the Colorado River Basin under dust-accelerated snowmelt, Science, in review.
Lawrence, C.L., Neff, J.C., and Farmer, G.L. (In Preparation) The influence of aeolian accretion on the geochemistry of high elevation soils of the southern Rocky Mountains, USA.
Lawrence, C.L., Neff, J.C., and Farmer, G.L. (Submitted) The relative contribution of aeolian dust and locally derived parent materials to high elevation soils of the southern Rocky Mountains, USA. Journal of Geophysical Research – Earth Surface.