Characteristics of the Potential Temperature Distribution Along Mountain Slopes Experiencing Cross-Mountain Air Currents in the Winter Season

In winter, northwesterly winds in the vicinity of Japan are predominant in the winter pressure distribution pattern that characterizes the climate of the environs of Japan, and on the Kanto Plain cross-mountain air currents frequently occur in winter because the winds pass over the Joshin’etsu mountainous region. A detailed analysis of the cross-mountain air currents is important to understanding the climate in the northwestern inland region of the Kanto Plain on the leeward side. In addition, little research has been conducted on the role of the gap flow in regard to the winter cross-mountain air currents. To address this shortage, advanced meteorological observation was carried out along the channel traversing the Joshin’etsu mountainous region, and that data was used to research the characteristics of the surface atmosphere along the mountain slopes when winter cross-mountain air currents blow. As a result, in the case in which cross-mountain air currents were not blowing, the potential temperature along the mountain slope tended to rise with altitude, in both the Sea of Japan side and Pacific Ocean side. However, in the case in which cross-mountain air currents were blowing, the potential temperature distribution was nearly uniform on the slope of the leeward, Pacific Ocean side, regardless of elevation. The case in which cross-mountain air currents were blowing had characteristics similar to foehn. This also suggests an impact by gap winds that pass through the Uonogawa-Tonegawa channel

〈報文〉超音波風速温度計と熱電対温度計による潜熱輸送量の簡単な評価方法

A simple method to estimate the vertical latent heat flux by a sonic anemometer-thermometer together with a fine thermometer is presented.An experimental result comparing with the lysimeter\u27s result is proved to be useful for the estimation of the vertical latent heat flux

〈報文〉フラット・アレイ型ソーダーについて

The outline of a Flat Array Type Doppler Sodar is discussed and the field test observations with the comparison of the sonic anemometer on the 30m tower are shown