Reference evapotranspiration (ETref) plays a vital role on climatological and hydrological researches, where spatial and temporal variations are a key indicator for climate change condition and water resources allocation (Jhajharia et al. 2009; Li et al. 2016; Sentelhas et al. 2010). The study on spatial and temporal changes of ETref has drawn much attention in recent decades to the regional-scale hydro-climatic change worldwide because of its nexus in the water resource management and terrestrial ecosystems (Burn and Hesch 2007; Shan et al. 2015; Tabari et al. 2012; Zhang et al. 2016). Additionally, ETref is not only helping for estimating agricultural water requirements, but also making irrigation planning and management (Gao et al. 2016a).
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1998; Liu and Zhang 2013). According to the Penman-Monteith method, most of the meteorological parameters are affecting by ETref including air temperature, wind speed, relative humidity and solar radiation. These four meteorological parameters contribute to the change in ETref which are elaborately assessed in this study. In addition, various attribution analysis techniques have been applied to determine the contribution of meteorological parameters on ETref changes. The most widely used technique is sensitivity coefficient analysis which has been employed to measure the probable change of ETref in response to an observed change of meteorological parameters (McCuen 1974; Wang et al. 2015). However, this method does not consider the evaporative process but it only shows the relative contributions of meteorological parameters on ETref changes. Roderick et al. (2007) pioneered a technique for attributing the change of evaporative demand through a full mathematical based formulation of pan evaporation. This mathematical approach has been commonly used to attribute the relative change in pan evaporation (Liu and McVicar 2012; Wang et al. 2015) but is occasionally used for ETref changes analysis. For instance, Li et al. (2016); Liu and Zhang (2013) used this technique appropriately for an attribution …show more content…
(2016) showed the inverse relationship between increasing temperature and decreasing evaporation in southwest China existed an evaporation paradox and the decreases contribution of wind speed to the changes of ETref offset the increases contribution of mean temperature. Wang et al. (2015) concluded that the contributions of net radiation, wind speed, actual vapor pressure are the major driving factors for the decrease in ETref for the three-river source region of China. Hence, further evaluation is essential to exhibit the relationship between meteorological parameters which attributes to changes in ETref in the Jiangsu Province, China based on attribution analysis of changes in ETref with a fully physical method which will be discussed in details in this
1998; Liu and Zhang 2013). According to the Penman-Monteith method, most of the meteorological parameters are affecting by ETref including air temperature, wind speed, relative humidity and solar radiation. These four meteorological parameters contribute to the change in ETref which are elaborately assessed in this study. In addition, various attribution analysis techniques have been applied to determine the contribution of meteorological parameters on ETref changes. The most widely used technique is sensitivity coefficient analysis which has been employed to measure the probable change of ETref in response to an observed change of meteorological parameters (McCuen 1974; Wang et al. 2015). However, this method does not consider the evaporative process but it only shows the relative contributions of meteorological parameters on ETref changes. Roderick et al. (2007) pioneered a technique for attributing the change of evaporative demand through a full mathematical based formulation of pan evaporation. This mathematical approach has been commonly used to attribute the relative change in pan evaporation (Liu and McVicar 2012; Wang et al. 2015) but is occasionally used for ETref changes analysis. For instance, Li et al. (2016); Liu and Zhang (2013) used this technique appropriately for an attribution …show more content…
(2016) showed the inverse relationship between increasing temperature and decreasing evaporation in southwest China existed an evaporation paradox and the decreases contribution of wind speed to the changes of ETref offset the increases contribution of mean temperature. Wang et al. (2015) concluded that the contributions of net radiation, wind speed, actual vapor pressure are the major driving factors for the decrease in ETref for the three-river source region of China. Hence, further evaluation is essential to exhibit the relationship between meteorological parameters which attributes to changes in ETref in the Jiangsu Province, China based on attribution analysis of changes in ETref with a fully physical method which will be discussed in details in this