Periodic fluctuation of reference evapotranspiration during the past five decades: Does Evaporation Paradox really exist in China?

Abstract

Evidence that the pan evaporation or reference evapotranspiration (ET0) as the indicator of atmospheric evaporation capability have decreased along with the continuous increase in temperature over the past decades (coined as “evaporation paradox”) has been reported worldwide. Here, we provide a nationwide investigation of spatiotemporal change of ET0 using meteorological data from 602 stations with the updated data (1961–2011). In addition, we explore the trigger mechanism by quantitative assessment on the contribution of climatic factors to ET0 change based on a differential equation method. In despite of different shift points regionally, our results suggest that the ET0 generally present decadal variations rather than monotonic response to climate change reported in previous studies. The significant decrease in net radiation dominate the decrease in ET0 before early 1990s in southern regions, while observed near-surface wind speed is the primary contributor to the variations of ET0 for the rest regions during the same periods. The enhancements of atmospheric evaporation capability after early 1990s are driven primarily by recent relative humidity limitation in China. From a continental scale view, as highly correlating with to Pacific Decadal Oscillation, the shift behaviors of ET0 is likely an episodic phenomenon of the ocean-atmosphere interaction in earth.

Hydrological projections of future climate change over the source region of Yellow River and Yangtze River in the Tibetan Plateau: A comprehensive assessment by coupling RegCM4 and VIC model

“…Exceeding the increasing trends in other part of northern hemisphere in the same latitude zones, the air temperature in TP has showed a warming of around 0.16 °C/decade since 1950s (Liu & Chen, ). Different from other regions with insignificant changing trends, the precipitation increased for most parts of the TP from 1960s (B. Wang, Bao, Hoskins, Wu, & Liu, ; Z. X. Xu, Gong, & Li, ), whereas the reference evapotranspiration in the TP based on updated data generally presents decadal variations rather than monotonic response to climate change reported in early studies (W. G. Wang, Shao, et al, ; W. G. Wang, Xing, et al, ; Xing et al, ). Meanwhile, frost and ice days in the eastern and central of the TP have significantly decreased from 1961 to 2005 (You, Kang, Aguilar, & Yan, ).…”

“…Wang, Bao, Hoskins, Wu, & Liu, 2008; Z. X. Xu, Gong, & Li, 2008), whereas the reference evapotranspiration in the TP based on updated data generally presents decadal variations rather than monotonic response to climate change reported in early studies (W. G. Xing et al, 2016). Meanwhile, frost and ice days in the eastern and central of the TP have significantly decreased from 1961 to 2005 (You, Kang, Aguilar, & Yan, 2008).…”

Climate Change, the Evaporation Paradox, and Their Effects on Streamflow in Lijiang Watershed

“…2002), who thought the reason was the sunlight decrease due to the increase in cloud coverage [11][12]. Stanhill et al (2001) also thought the reason was the sunlight decrease while due to the increase in aerosol concentration [32].…”

“…The contrast between temperature increase and potential evapotranspiration decrease is called the "evaporation paradox" [11].…”

Untitled

“…Liu & Zhang 14 indicated that in the driest Northwest region of China, ET 0 decreased from 1960 to 1993 at the rate of 2.34 mm/year and increased thereafter up to 2010 at the rate of 4.80 mm/year. Xing et al 15 reported decadal variations in the ET 0 . Gao et al 16 reported a decreasing trend in ET 0 at 46.7% of the weather station sites and an increasing trend in ET 0 at 53.3% of the sites for the period of 1960 to 2012 in the arid and semiarid area of the West Liao River basin of China.…”