Statistical Investigation of the Surface Temperature of the Sea off Hatinohe (I)

Abstract

Many authors dealt with the investigations of the sea surface temperature, for the purpose of obtaining the relation between the cool summer in North Japan and the cool temperature of the sea surface. In this paper, by investigating the data of the routine oceanographical observations made in the last three (or two) years, Sept. 1936-Aug. 1939 (1938), the author obtained some statistical results as follows.
1. In summer season, May-Sept., at the coastal A station there are generally found warmer temperatures than those at stations five (B) and ten miles (C) off the coast, while in winter their relationship is reversed, Oct. and April being the period of interchange. An exception to this rule is found with the surface layer in which water is almost warmer off-shore (B and C) than at the coast throughout the year except June.
2. The modes of the annual variation of water temperature, especially that of the phase lag varies with the depth.
3. We could recognize the so-called “Tugaru Warm Current” at B and C stations in summer without respect to salinity.
4. Under the weather types such as so-called “summer type” as well as “high area type”, the water temperature has tendency to rise or is higher than normal temperature at the season and under the type of “low area”, of “line of discontinuity” and of the “Okhotsk high”, the sea temperature has a tendency of gradual descent or is lower than the normal.