東京都心における高温日の湿度の経年変化  [in Japanese] Long-term Humidity Changes on Hot Days in the Central Part of Tokyo  [in Japanese]

東京都心(大手町)における相対湿度と水蒸気圧の40年間(1961〜2000年)の経年変化を日最高気温の段階別に調べた.その結果,日最高気温が33〜36℃の日には,それより気温の低い日に比べ,午後(15時)の相対湿度の経年変化率に数%/(40年),水蒸気圧には0.5〜1hPa/(40年)の正偏差すなわち相対的な上昇傾向が認められた.この上昇傾向は,冷房による水蒸気排出の影響である可能性が示唆された。

Long-term trends of relative humidity and vapor pressure in the central part of Tokyo were evaluated from forty years' data, which were stratified with daily maximum temperature. It was found that the changing rates of relative humidity and vapor pressure for days with maximum temperature of 33-36℃ showed a positive anomaly of a few percent and 0.5-1 hPa per 40 years, respectively, in comparison to those for days with lower temperature. This fact suggests the effect of water vapor emission from cooling towers on urban humidity.