Budget Analysis on the Sea Effect Snow Observed along the Japan Sea Coastal Area

Abstract

Basing on the aerological observations by smaller scale network which were set up in January of 1963, 1964 and 1965 in Hokuriku district, the Japan Sea coastal area of central Japan, the heat and moisture budgets were compared among these three years. The flux divergence of vapor assumes nearly the same values for three winters, whereas the amount of precipitation changes very much from year to year. Although the difference in the evaporation from the sea surface and that in the convective transfer are estimated to be of considerable amount, the precipitation is principally related to the net transport of condensed water either from or to the surrounding region.
The vapor import in 6 hours is compared with 6 hourly precipitation within the region. Better relation is found in the precipitation onto the downstream side stations. It is shown that the sensible heat increment is nearly twice as much as the latent heat decrement if they are computed by mean flow flux divergence. This circumstance is observed well in the cloud layer regardless to the scale of network. The surplus of the heat energy must be transported by convective activity. It is suggested that, when heavier snowfall is observed, the convective activity is so predominant that the more heat energy than that supplied from the sea surface is transported into the cloud layer.