ANOMALOUS WINTERTIME PRECIPITATION IN THE WESTERN UNITED STATES AND RELATED METEOROLOGICAL VARIABLES.
Abstract
Significant anomalies of monthly precitation in the western United States are related to (1) anomalies of sea-surface temperatures in the eastern North Pacific Ocean, (2) anomalous flow associated with departures from normal sea-level pressure, and (3) differences in the flux of moisture. Examples are given showing that large-scale anomalies of temperatures of the ocean surface are coherent, making detection from month to month possible; these anomalies greatly influence the circulation of the overlying atmosphere and, in turn, are influenced greatly by the ever-changing atmospheric flow. The underlying ocean controls the development of large cyclones and anti-cyclones that persist for weeks, months, or even seasons by being a main source of moisture and energy. Anomalous geostrophic flow, related to departures from normal monthly sea-level pressure, are shown to be related closely to the distribution of anomalies of precipitation during the winter wet season. Anomalous flow off the land (or parallel to the coast) almost always is associated with a decrease in the amount of precipitation because the supply of moisture available for condensation is greatly diminished by such a trajectory. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1970
- Accession Number
- AD0710242
Entities
People
- Lalovee G. Cobb
Organizations
- Texas A&M University