Book contents
- Frontmatter
- Contents
- Preface
- Acknowledgments
- Part I The dryland environment
- Part II The meteorological background
- Part III The climatic environment of drylands
- 9 Defining aridity: the classification and character of dryland climates
- 10 Desert microclimate
- 11 Precipitation in the drylands
- 12 Hydrologic processes in the drylands
- 13 Desert winds and dust
- Part IV The earth’s drylands
- Part V Life and change in the dryland regions
- Index
- References
13 - Desert winds and dust
from Part III - The climatic environment of drylands
Published online by Cambridge University Press: 05 November 2011
- Frontmatter
- Contents
- Preface
- Acknowledgments
- Part I The dryland environment
- Part II The meteorological background
- Part III The climatic environment of drylands
- 9 Defining aridity: the classification and character of dryland climates
- 10 Desert microclimate
- 11 Precipitation in the drylands
- 12 Hydrologic processes in the drylands
- 13 Desert winds and dust
- Part IV The earth’s drylands
- Part V Life and change in the dryland regions
- Index
- References
Summary
Surface winds
Many deserts are characterized by a steady and intense daytime wind that blows with a noisy roar, and utter stillness of the wind in the desert night. This wind regime is a result of two factors, the aerodynamic smoothness of the barren desert surface and the extreme temperature gradients near the surface.
Surface roughness z0 is small in arid regions, so that wind speeds increase rapidly within the first few meters of the surface. Among the world’s deserts, however, roughness varies by about an order of magnitude. One of the smoothest surfaces is the Bonneville salt flats, an ancient lake bed in Utah (Fig. 13.1). The roughness of a similar dry lake bed in California was measured to be 0.003 (Vehrencamp 1951). Its smoothness is indicated by the land-speed records set there: 622 mph (~1000 km/h) for a rocket-powered vehicle in 1970, and 407 mph (655 km/h) for gasoline engines.
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- Chapter
- Information
- Dryland Climatology , pp. 230 - 254Publisher: Cambridge University PressPrint publication year: 2011