Sensitivity of Reference Evapotranspiration to Global Warming in the Caspian Region, North of Iran

摘要: The goal of this study was to estimate the sensitivity reference evapotranspiration (ET 0) changes in meteorological parameters Caspian region. Long-term data (1961-2008) were obtained from three synoptic stations. region primarily classified into climatic zones, based on De Martonne climate classification. Penman–Monteith equation applied calculate ET 0 and studied terms air temperature, solar radiation, wind speed vapor pressure within a possible range ±20% normal long-term parameters. results indicated that could be classes: Mediterranean, humid, extremely humid. During last half century, and, particular, temperature has changed dramatically increased as result change. suggests an increase by 20% (approximately 3.3 oC) will demand 16%. Changes (20%) represented highest inverse effect annual throughout (-19% -30% other climates). Mediterranean humid climates showed 2 5% total 0, respectively, response change speed. It is quite essential for managers take consideration expected owing global warming while planning development artificial natural ecosystems