Observations of thermal microstructure in the Kuroshio off of Southern Honshu and Shikoku

  • Harold Solomon
Original

Abstract

Direct observations of thermal microstructure within the main stream of the Kuroshio show that within the region of the most steeply sloping isotherms, from about 180 to 360 m depth near the current axis, considerable microstructure is present, and the laminae tend to be approximately aligned along the sloping isothermal surfaces rather than horizontally. Away from the axis, the slopes of the isotherms are considerably less so that the tendency for alignment along isotherms, if present, is not noticeable. Laminae rarely if ever extend for as much as 6 miles in the cross-current direction. Lateral temperature variations within individual laminae are small; to the extent that they do occur there is no apparent tendency for density to be conserved.

Some of the temperature features seem to correspond to small local maxima in the vertical salinity profile. More experimental evidence and better understanding of STD spiking (from causes other than the time-constant mismatch, which is clearly not the cause here) is required before it can be concluded that these local maxima are real. If real, they would provide evidence that local vertical mixing alone cannot produce the thermal microstructure in this region. The main conclusion, however, is that STD salinity measurements are not very reliable at the present time.

Keywords

Microstructure Temperature Variation Experimental Evidence Local Maximum Direct Observation 

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Copyright information

© The Oceanographical Society of Japan 1974

Authors and Affiliations

  • Harold Solomon
    • 1
  1. 1.Department of Environmental SciencesTel Aviv UniversityRamat AvivIsrael

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