Abstract
A cold air flow which is called a “Land Breeze” often appears within Ishikari Bay in winter seasons. The flow goes down from the cold mountain area to creep into the com-paratively warm surrounding atmosphere. It is known that Sapporo has a heavy snowfall when a cold flow generates to develop snow cloud within Ishikari Bay. The present study attempts to analize the stretch and the vertical shape of a cold air flow by using the one dimensional two layer model. Stability for the cold air layer is also discussed.
As a result, it is found that the stable frequency domain becomes wider when the inner Froud number becomes greater and the ground slope becomes smaller. And by considering the thermal effect, a stretch length and a vertical shape of the cold air layer could be derived; they agreed qualitatively with the observed data obtained with Doppler Radar.
