作者: P. Ted Strub , Corinne James
关键词: Wind stress 、 Geology 、 Trough (meteorology) 、 Sea level 、 Spatial ecology 、 Climatology 、 Storm 、 Empirical orthogonal functions 、 Oceanography 、 Spring (hydrology) 、 West coast 、 Earth-Surface Processes 、 Ecology (disciplines) 、 Earth and Planetary Sciences (miscellaneous) 、 Space and Planetary Science 、 Palaeontology 、 Forestry 、 Aquatic science 、 Atmospheric Science 、 Soil science 、 Geochemistry and Petrology 、 Geophysics 、 Water Science and Technology
摘要: We examine large-scale atmospheric behavior around the time of spring and fall transitions in coastal ocean off west coast North America. Records adjusted sea level (ASL), wind stress, pressure (SLP), 500-mbar heights for years 1971–1975 1980–1983 are analyzed. The records cover periods 91 days, centered on dates as determined from data. Empirical orthogonal functions obtained ASL, SLP records. two dominant modes ASL stress similar times both transitions, series these highly correlated with one another. Transitionlike is evident first fall, but transition more pronounced. Principal estimator patterns, formed empirical show spatial patterns which force during transitions. pattern coincides formation a high-pressure system at 45°N 140°W along development low-pressure cell over southwest continental United States. Inspection height composites days surrounding 9 reveals ridging diffluent flow western States transition; following transition, relaxes continent remains duration 45 examined here. characterized by rise particularly north 40°N, change southward to northward stress. involves appearance America 50°N 140°W, representing passage synoptic storms through region. Prior somewhat trough southwestern States; after northeast Pacific nearly zonal.