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Dust storms have a great many environmental implications in the world's dry lands where they are particularly common. Four main classes of dust event are identified and defined: dust storms, dust haze, blowing dust and dust devils. The geography of dust storms is analysed in each of eight major world regions: Africa, the Middle East, South-west Asia, Europe and the USSR, China, Australia, North America and Latin America. Terrestrially observed meteorological data and data from remote sensing platforms are employed to identify the major source areas in each region, their seasonality, diurnal patterns of activity and trajectories of long-range transport. Among the important controls on the frequency distribution of dust storm activity are the meteorological conditions that generate dust-raising winds, and a number of meteorological systems commonly cause dust storms in all global regions. These include low pressure fronts with intense baroclinal gradients, pressure gradient winds between moving or stationary air masses, katabatic winds and convectional cells. The nature of the surface upon which deflation occurs is also important; typical dust-producing geomorpholological units include alluvial spreads, lacustrine deposits, desert depressions, loess deposits and reactivated fossil dunes. Dust storm activity is prone to considerable variation. The seasonal characteristics are explicable with reference to the meteorological systems generating dust, the state of ground cover, particularly vegetation, and the effects of seasonal rainfall. Substantial variations also occur from year to year, and land use and climatic variations can substantially affect their occurrence.

The structure of macrobenthic communities was investigated in carbonate and transitional carbonate-terrigenous sediments of the Southern Gulf of Mexico (Campeche Bank). The aim was to assess the influence of natural disturbance represented by winter storms and river runoff and the putative influence of oil-related activities using a regional approach. At a scale of > 100 km community composition of benthic macroinfauna was characterised as distinct assemblages within the carbonate and transitional sedimentary provinces controlled by natural disturbance. The carbonate assemblage was numerous and diverse influenced by a heterogeneous substratum. Winter storms had a severe impact with mortality probably resulting from abrasion and passive transport causing low values of number of taxa, abundance, biomass and diversity measurements. Conversely, on the transitional shelf a sequence of disturbance from river runoff and winter storms resulted in a general impoverished community due to fine sedimentation and sediment instability. Immediately after the rainy season, values of biological measures were low, but the severity of disturbance was contingent with depth. At a scale of 10s km within the transitional shelf, the combined effect from natural and anthropogenic disturbance caused extremely low values of biological measures within the so called oil exclusion zone. Despite the lack of adequate controls the effects of oil related activities were identified as severe reductions in macroinfauna densities and biomass resulting in a very simple community. Large spatial variability at this scale masks the temporal variation observed in other areas of the Campeche Bank and the relationship between biological measures and indicators of oil activities (Barium, Nickel and oil-hydrocarbons). Finally the increased variability resulting from the influence of oil activities interrupts the natural gradient of macroinfauna patterns across the shelf.

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No description available.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1988. / Vita. Abstract. Includes bibliographical references (leaves 170-171). Also available via the Internet.

Thesis (M.S. in Meteorology)--Naval Postgraduate School, March 2009. / Thesis Advisor(s): Nuss, Wendell A. "March 2009." Description based on title screen as viewed on April 23, 2009. Author(s) subject terms: Potential Vorticity, Severe Weather, Supercell, Weather Research and Forecasting Model, Advanced WRF. Includes bibliographical references (p. 43-47). Also available in print.

Thesis (M.S. in Meteorology)--Naval Postgraduate School, March 2009. / Thesis Advisor(s): Nuss, Wendell. "March 2009." Description based on title screen as viewed on April 23, 2009. Author(s) subject terms: Severe Weather, Conditional Instability, Potential Instability, Discriminate Analysis, Theta-e, Lapse Rate, Ridge Axis Formula Includes bibliographical references (p. 89-91). Also available in print.

Thesis (M.S.)--Florida State University, 2004. / Advisor: Dr. Paul Ruscher, Florida State University, College of Arts and Sciences, Dept. of Meteorology. Title and description from dissertation home page (viewed Jan. 13, 2005). Includes bibliographical references.

Thesis (M.S.) in Forestry--University of Maine, 2001. / Includes vita. Includes bibliographical references (leaves 120-125).