Temporal Changes of Salinity, Temperature, and Dissolved Oxygen Content of the Water at Station "P" in the Northeast Pacific Ocean, and Some of Their Determining Factors
Oceanographic data collected at Ocean Weather Station "P" (Lat. 50°N, Long. 145°W) during the 2 years between August 1956 and July 1958 are presented to show the principal features of the variations of salinity, temperature, and dissolved oxygen content of the water at the station. Probable factors influencing the water properties are discussed and explanations are given to account for these variations. Only those causing changes in the upper zone are discussed in detail.There is good agreement between the observed changes of salinity in the upper zone and changes attributable to the effect of precipitation minus evaporation for the period summer through winter, 1956. However there is generally poor agreement for the rest of the period. The main factor influencing temperature in this zone is heat transfer at the air–sea boundary. Changes of dissolved oxygen content in this zone are governed primarily by changes of solubility of oxygen in water.Horizontal transport of water in the locality influences the properties at the station appreciably. The general increase of salinity, temperature, and dissolved oxygen content that occurred during summer 1957 through summer 1958, is attributed to the northward transport of water. Transport, both from the region of the "dome" located northwest of the station, and from the west, also appears to influence the properties of water at the station during autumn and winter. Intense vertical mixing during autumn and winter affects the structure of water in the upper zone by redistributing the properties.