Oceanographic Observations North Pacific Ocean Station November and Pacific Standard Monitoring Sections P3, P4, P5, and P6, July 1966-June 1974. Terminial Report.

摘要

Observed and interpolated temperature and salinity data with computed sigma-t values are reviewed for all oceanographic stations occupied by U.S. Coast Guard cutters at Ocean Station NOVEMBER (30 deg 00 N, 140 deg 00 W) and Pacific Standard Monitoring Sections P3, P4, P5, and P6 from July 1966 through June 1974. The analysis of OS NOVEMBER for these eight years compares favorably with seasonal analyses made previously. The water properties show certain seasonal trends with near-surface density appearing to be primarily controlled by temperature. The mixed layer demonstrates an annual growth and decay dependent on changes in atmospheric conditions. The depth of this layer varies from 150 m in March to 10 m in September. Temperatures have an annual periodicity; salinity has a semi-annual periodicity. There is great year-to-year variability in the seasonal layer. Anomalous decreases in temperature were usually accompanied by decreases in salinity. Vertical sections of temperature and salinity for Standard Sections P3, P4, P5, and P6 are examined to determine the seasonal variations of the boundaries between the Pacific Central Water, the Pacific transition zone, and the California Current. These water masses and the limits of their boundaries are identified by the characteristic rising of isotherms and isopycnals, T vs S relationships, and intense horizontal salinity gradients.