How Has the Recent Climate Change Affected the Spatiotemporal Variation of Reference Evapotranspiration in a Climate Transitional Zone of Eastern China?

Reference evapotranspiration (ET0) is essential for agricultural production and crop water management. The recent climate change affecting the spatiotemporal variation of ET0 in eastern China continues to still be less understood. For this purpose, latest observed data from 77 meteorological stations Anhui province were utilized determine variations by use Penman–Monteith FAO 56 (PMF-56) model. Furthermore, Theil–Sen estimator Mann–Kendall (M–K) test adopted analyze trends factors. Moreover, differential method was employed explore sensitivity factors contributions trends. Results show that decreased significantly before 1990, then increased slowly. commonly higher north lower south. most sensitive relative humidity (RH), except summer. However, summer, net radiation (Rn) factor. During 1961–1990, Rn leading factor annually, during growing season while wind speed (u2) played a role others. All provide negative trends, which ultimately lead decreasing 1991–2019, changed mean temperature (Ta) season, spring Overall, u2 cannot offset positive Ta RH, slow upward dramatic drop amount contributes changes Region III also worth noting.