Reference Evapotranspiration Changes: Sensitivities to and Contributions of Meteorological Factors in the Heihe River Basin of Northwestern China (1961–2014)

Table 2

Means of seasonal and annual and their trends in the three subregions during 1961–2014.

Region		Annual	Spring	Summer	Autumn	Winter
Upper region	Mean (mm yr^−1)
	Trend (mm⋅10 yr^−2)	6.61	2.41	1.33	1.19	1.54
Middle region	Mean (mm yr^−1)
	Trend (mm⋅10 yr^−2)
Lower region	Mean (mm yr^−1)
	Trend (mm⋅10 yr^−2)

Note: means the significance level of 0.1.