We conduct trends and change point analysis for the area-averaged ET0 in the resulted eight sub-regions by the means of the segmented regression model (shown in Fig. 2 and Table 1). The overall impression from the temporal patterns in ET0 series is that shift trends can be evidently found in all eight sub-regions, although the turning years and the number of change points are regionally different. The decreasing-increasing (DI) patterns (with one joint point) are detected in EC, SE and SW regions with joint points happening at about 1992, 1992 and 1995, respectively. The zigzag increasing-decreasing-increasing (IDI) patterns (with two joint points) are depicted in TP (1973 and 1993) and NW (1977 and 1995) regions. With three joint points, approximating to periodic variation, more complex zigzag increasing-decreasing-increasing-decreasing (IDID) patterns are identified in NC (1973, 1991 and 2000) and NE (1978, 1993 and 2003) regions. It should be noted that although only two points of 1992 and 2002 are found in NP region, the overall changing pattern of decreasing-increasing-decreasing for ET0 are similar to NC and NE regions, especially for the recent two decades. Interestingly, irrespective of complex shift trends reflected by different number of joint points and turning modes, multidecadal changing features in ET0 are characterized by an evident spatial clustering partition. This clustering partition can roughly indicates that DI patterns mainly occur in southern region in China with a humid climate, whereas IDI mostly emerge in western Plateau regions with a cold and drought climate and IDID mainly appear in north and northeast regions with a cold climate. We also investigate the trends for the 602 stations during the segmented periods according to the corresponding regional change points. Taking EC region for example, as shown in Fig. 3, annual ET0 at all stations decrease during 1961–1991 by 0–8 mm yr−1 (over 23% stations by 4–8 mm yr−1), of which over 80% stations are statistically significant at 95% confidence level (p < 0.05). As for as the second segmented period, from 1992–2011, more than 65% stations (over 30% stations by 4–12 mm yr−1) are dominated by increasing trends in ET0 despite that only 35% stations are statistically significant at 95% confidence level (p < 0.05). Such extremely distinct spatial patterns in ET0 during the adjacent segmented period are also identified in other homogeneous regions (shown in Figure S2–S8), giving us confidence in detecting multidecadal changes in ET0 with shift trends in China.