A Model for Orographic Precipitation in the North-Central Great Basin
1979; American Meteorological Society; Volume: 107; Issue: 11 Linguagem: Inglês
10.1175/1520-0493(1979)107 2.0.co;2
ISSN1520-0493
Autores Tópico(s)Meteorological Phenomena and Simulations
ResumoThe orographic effect, measured as the ratio of mountain to valley precipitation at 72 pairs of stations in the north-central Great Basin, was tested against 29 relief, location and synoptic parameters. Parameters found significant were then subjected to stepwise multiple regression to develop equations explaining the spatial variation of precipitation for each calendar month, two synoptic seasons and the year. The monthly and seasonal equations explained 52–83% of spatial variance and the annual equation 65%. They showed that the ratio increased with station elevation difference and in winter with proximity to the Pacific Ocean; significant relationships also occurred with station pair orientation, and in summer with ocean direction and Pacific storm rainfall. Best results were obtained either for pairs with long-term records or those with both stations topographically close together. An equation using mean monthly Great Basin wind speed and Pacific storm rainfall explained 88% of the annual variation in the Basin mean monthly orographic ratio.
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