Impacts of Climatic Change on Reference Crop Evapotranspiration across Different Climatic Zones of Ningxia at Multi-Time Scales from 1957 to 2018

Table 2

Trend analyses of climate factors with Mann–Kendall test and climate tendency rate.

Climate region	Climate factor	Climate tendency rate			Climate factors average value			Change point
		1957∼1990	1991∼2018	1957∼2018	1957∼1990	1991∼2018	1957∼2018
NX (whole)	Tmean (°C)	0.094	0.451	0.34	7.16	8.33	7.69	1993
	Tmax (°C)	−0.044	0.446	0.31	21.66	22.82	22.18	1995
	Tmin (°C)	0.385	0.548	0.51	−6.05	−4.41	−5.31	1989
	RH (%)	0.121	−1.598	−0.42	56.82	55.59	56.27	1992
	SD (h)	0.039	−0.094	−0.03	7.55	7.44	7.50	1994
	U2 (m/s)	−0.108	−0.365	−0.10	2.63	2.43	2.54	1988
NYR	Tmean (°C)	0.145	0.531	0.38	7.92	9.19	8.49	1992
	Tmax (°C)	−0.051	0.643	0.36	22.28	23.55	22.85	1994
	Tmin (°C)	0.454	0.57	0.54	−5.47	−3.75	−4.70	1989
	RH (%)	0.036	−2.446	−0.81	55.70	53.25	54.59	1996
	SD (h)	0.032	−0.096	−0.05	7.98	7.76	7.88	1995
	U2 (m/s)	−0.057	−0.551	−0.08	2.47	2.36	2.42	1991
CAZ	Tmean (°C)	0.193	0.263	0.31	7.83	8.92	8.32	1992
	Tmax (°C)	−0.063	0.288	0.24	22.93	23.90	23.37	1995
	Tmin (°C)	0.665	0.135	0.48	−5.48	−3.99	−4.81	1988
	RH (%)	−0.444	0.071	−0.06	51.42	51.45	51.43	1989
	SD (h)	0.017	−0.011	−0.04	7.95	7.81	7.88	1989
	U2 (m/s)	−0.157	−0.278	−0.11	2.93	2.71	2.83	1994
SMA	Tmean (°C)	0.029	0.558	0.32	5.73	6.87	6.24	1990
	Tmax (°C)	−0.019	0.407	0.33	19.79	21.00	20.34	1992
	Tmin (°C)	0.013	0.939	0.49	−7.19	−5.51	−6.43	1991
	RH (%)	0.774	−2.42	−0.4	63.34	62.08	62.77	1990
	SD (h)	0.1	−0.175	−0.4	6.73	6.76	6.75	1988
	U2 (m/s)	−0.109	−0.267	−0.11	2.48	2.21	2.36	1987