||Pacific Ocean Influence Upon California Rainfall.
Pyk, Charles B. ;
Bjerkne, Jacob ;
||California Univ., Los Angeles. Water Resources Center.
||UCAL-WRC-W-254; OWRR-A-021-CAL; 06115,; A-021-CAL(3)
( Rainfall ;
Correlation techniques ;
Air masses ;
Jet streams(Meteorology) ;
Spring season ;
Pacific Ocean ;
||Some EPA libraries have a fiche copy filed under the call number shown.
The climatic patterns of precipitation in the western United States and Baja California were examined in considerable detail. Of particular concern are the three prominent seasonal precipitation maxima: the winter maximum which occurs in all coastal and most interior sections, the summer maximum in the interior deserts of the southwestern United States and in Baja California, and the late spring maximum in the interior of the Pacific Northwest United States. The winter precipitation maximum is associated with extratropical cyclones of the north Pacific Ocean; and in the mean this maximum progresses generally southward along the west coast of the United States with time, occurring in early December in northwestern Washington and in mid-February in portions of coastal southern California. This southward progression appears to be related to the general southward displacement of the mean upper tropospheric jet stream and the associated north Pacific storm track during the late fall and winter. The warm-season rainfall maxima which are observed in the interior portions of the western United States and Baja California appear to result primarily from convective activity occurring within warm, unstable air masses. (WRSIC abstract)