Wind regimes and aeolian transport in the Great Basin, U.S.A

In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: a b s t r a c t a r t i c l e i n f o The modern Great Basin of the interior western United States is characterized by surface winds with considerable spatial and temporal variabilities. Wind records from the second half of the 20th century for 12 Great Basin localities, analyzed with standard aeolian-sediment transport methods developed elsewhere in the world, reflect this complexity. The drift potential (DP) for aeolian deposits is generally moderate (DP 200– 400) in the western Great Basin and weak (DP b 200) in the central Great Basin where winds are predominantly west-southwesterly. DP is relatively high (DP N 300) at the eastern edge of the Great Basin where the dominant prevailing wind direction is south-southwesterly. Both DP and resultant drift direction (RDD) are consistent with synoptic meteorological observations of the evolution of cold fronts in the Great Basin. Meteorological observations show that effective winds to produce dunes are most commonly the result of late winter–early spring cyclogenesis. There has been considerable temporal variability of DP in the latter half of the 20th century. Most of the Great Basin has experienced decreasing wind strength since 1973, consistent with recent studies of wind strength in North America and elsewhere. Dune morphology matches both localized RDD and temporal variations in DP reasonably well in the Great Basin. The results demonstrate that local topography can have an important influence on wind directionality, thus providing a cautionary note on the interpretation of dune morphology in the paleoclimatic and stratigraphic record. Aeolian sediment transport is important for the evolution of modern desert landscapes as well as the formation of sedimentary deposits in the geologic record. Aeolian transport and the formation of sand dunes is a function of the availability of transportable sediment, the net evaporation–precipitation of a given region, and the magnitude and variability of surface wind fields (e. Interpretation of the climatic control of modern aeolian deposits thus has a direct relationship to the paleoclimatic interpretation of ancient aeolian sedimentary sequences. Surface wind regimes and their associated aeolian deposits have significant spatial and temporal variabilities (e.g., McKee, 1979). While numerous studies have related specific aeolian …