Duration of Surface Wind Speeds.
COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH
Pagination or Media Count:
In this study of surface winds, statistical data on the probability of certain speeds occurring during specific consecutive time periods are presented. The nine stations selected for study were chosen on a basis of period of record and distribution throughout the United States. Analysis of mean monthly values Table III shows that, except for sheltered locations like Riverside and Sacramento, California, winds of 7-16 knots and of or to 12 hours duration occur more often than higher or lower wind speeds of similar duration. Occurrences of calm periods 7 hours in duration were notably high at Riverside, and Bedford. Fairfield and Great Falls report the highest frequency of winds of 1 hour duration and 16 knots. Locations considerably distant from each other, for example Bedford, Mt. Clemens and Fort Worth, provided similar mean and probable highest monthly occurrence values Table III and IV. This is true despite the fact that the topography, synoptic meteorology patterns, air masses and local wind controlling effects at these stations differ. In addition, general agreement was found in the particular seasons in which these events were observed. At some sites possible causes for a particular wind environment are indicated from the data. For example, the few instances of calm at Jacksonville are in contrast to the many found at Riverside. This difference is probably due to the dissimilarity in exposure which affects factors like the persistent and intensity of land and sea breezes at the two stations. Using the data given in Table IV an investigation was conducted on the seasonal occurrence of all wind speeds of or 2 hours duration.