Statistical Analysis for the Detection of Change Points and the Evaluation of Monthly Mean Temperature Trends of the Moulouya Basin (Morocco)

Table 4

Results of the 3 change point detection methods applied to monthly mean temperature data, January–June, between 1980 and 2020 in the Moulouya watershed.

	January			February			March			April			May			June
	P value	Significance	Date	value	Significance	Date	value	Significance	Date	value	Significance	Date	value	Significance	Date	value	Significance	Date
Pettitt’s test
S1	0.023		1992	0.625	N	—	0.161	N	—	≤0.01		1996	≤0.01		1998	≤0.001		1997
S2	0.156	N	—	0.878	N	—	0.646	N	—	0.013		2007	0.068	N	—	≤0.001		1998
S3	≤0.01		1992	0.207	N	—	0.031		1995	≤0.01		1995	≤0.001		1998	≤0.01		1996
S4	0.048		1992	0.036		2004	0.305	N	—	0.021		1996	≤0.001		1998	≤0.001		1997
S5	0.468	N	—	0.798	N	—	0.550	N	—	≤0.01		2007	≤0.001		2004	≤0.001		1999
S6	0.448	N	—	0.303	N	—	0.287	N	—	≤0.01		2009	≤0.01		1993	≤0.01		1992
S7	0.087	N	—	0.109	N	2006	0.021		1999	≤0.01		1997	0.161	N	—	0.378	N	—
S8	0.010		1994	0.390	N	1993	0.176	N	—	0.014		2004	≤0.01		2004	≤0.01		1998
S9	0.013		1992	0.089	N	1998	0.234	N	—	≤0.01		1996	≤0.001		1998	≤0.001		1997
Buishand’s range test
S1	0.114	N	—	0.439	N	—	0.130	N	—	0.013		1996	≤0.001		1998	≤0.001		1997
S2	0.305	N	—	0.876	N	—	0.725	N	—	≤0.01		2007	0.030		2004	≤0.001		1999
S3	0.015		1992	0.175	N	—	0.020		1995	≤0.01		1995	≤0.001		1998	≤0.01		1996
S4	0.220	N	—	0.020		2004	0.279	N	—	0.065	N	—	≤0.001		1998	≤0.001		1997
S5	0.268	N	—	0.682	N	—	0.448	N	—	≤0.001		2007	≤0.001		2004	≤0.001		1999
S6	0.364	N	—	0.318	N	—	0.349	N	—	≤0.01		2009	0.015		1994	≤0.01		1992
S7	0.044		2009	0.183	N	—	0.028		1999	≤0.01		1997	0.167	N	—	0.192	N	—
S8	0.147	N	—	0.396	N	—	0.200	N	—	0.01		2004	≤0.01		2004	0.011		1998
S9	0.142	N	—	0.012		1998	0.218	N	—	≤0.01		1996	≤0.001		2004	≤0.001		1997
von Neumann ratio test
S1	≤0.001			0.020			0.139	N		0.26	N		0.026			≤0.01
S2	≤0.01			0.566	N		0.135	N		0.256	N		0.271	N		0.075	N
S3	≤0.001			≤0.01			≤0.01			≤0.01			≤0.001			0.195	N
S4	≤0.001			≤0.01			≤0.01			0.278	N		≤0.01			≤0.01
S5	≤0.01			0.738	N		0.223	N		≤0.01			≤0.01			≤0.001
S6	≤0.01			0.098	N		0.450	N		0.026			0.074	N		0.131	N
S7	≤0.01			0.518	N		0.607	N		0.03			0.604	N		0.015
S8	≤0.001			0.494	N		0.151	N		0.07	N		≤0.01			≤0.01
S9	≤0.001			≤0.001			0.164	N		0.02			≤0.001			0.011

N, no significant change point. Significant point of change at 0.1 level. Significant point of change at 0.05 level. Significant change point at 0.01 threshold.