Research Abstracts 1992-1993: Report No. 93-05

Barbour, P.L. and S. N. Walker, "The Influence of Synoptic Circulation Patterns on Surface Wind Characteristics," OSU Wind Research Cooperative, WRC Report No. 93-05, October 30, 1993, 149 pp., $37.25

A climatology of circulation pattern types for the Pacific Northwest (WRC 93-04) is used to examine the relationship between different types of circulation patterns and surface wind characteristics at several sites in the region.  Wing statistics are compiled and examined for each circulation pattern category during each month.  Detailed discussions of the characteristics for January and July are presented.  results show that at most sites, a good relationship exists between the surface wind properties and the type of circulation pattern present.  The circulation pattern climatology is shown to be a useful tool for identifying and examining the important meteorological properties at perspective wind sites.

The circulation pattern climatology is also used to assess the potential effects of a shift observed in climatological and environmental parameters around 1976. Changes in most of the significant circulation pattern types were observed between the periods 1960-1975 and 1976-1989 for nearly every month with a decrease in some categories reaching nearly 10.0%. Frequency weighted mean wind speeds are computed and used to assess the influence of these changes. Results show that for the three sites examined, the annual mean wind speed for the period between 1976 and 1989 was lower than the mean for the period between 1960 and 1989.