摘要
利用彭曼公式计算 80年代以来黄河上游流域蒸散量 ,分析了该地区蒸散量、日照时数、气温、空气饱和差等气候因子的变化趋势 ,并着重研究了诸因子对蒸散量的影响。研究发现 ,黄河上游流域蒸散量呈逐年增大趋势 ,并以每年 3.2 5 mm的速度递增 ;而作为主要影响因子的日照时数则以每年 3.6小时的速度增加 ;气温同样表现出逐年升高的趋势 ,其气候倾向率为 0 .4℃ /1 0年 ;空气饱和差也以每年 0 .0 2的速度递增 ;因此 ,可以认为 ,黄河上游流域日照时数、气温及饱和差的增加 ,加剧了草地蒸散量的增大 。
Penman formula was used to calculate the evapotranspiration in the upper valley of the Huanghe river since 1980.The variation tendency of some climatic factors,such as evapotranspiration,sunshine duration,air temperature,air saturation deficit and etc,were analysed.The dry climate impact on the evapotranspiration in the area was focused in the study.The results show that the evapotranspiration is increasing annually with the speed of 3 25 mm in the area;while the sunshine duration which is considered as main impact factor,is increasing with 3 6 hour/year;air temperature is appearing the increasing tendency,and its climatic tendency is 0 4℃/10 years;air saturation deficit is increasing with 0 02/year.Therefore,It is suggested that the evapotranspiration is greatly increasing as increment of sunshine duration,air temperature and air saturation deficit in the area.But the increment of evapotranspiration and decrement of precipitation amount impact directly on the decrement of flow curve and expanding of grassland′s desertization in the upper valley of the Huanghe river.
出处
《气象》
CSCD
北大核心
2000年第2期6-10,共5页
Meteorological Monthly
关键词
黄河上游
彭曼公式
蒸散量
影响因子
dry climate the upper valley of Huanghe Penman formula evapotranspiration
