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Large-scale agricultural activities can intensify atmospheric–terrestrial interactions, of which precipitation recycling plays a critical role. During 1982–2018, irrigated area has dramatically expanded in Northwest China (NWC). In this study, a regional precipitation recycling model—the Brubaker model was used to investigate the precipitation recycling ratio (PRR) and recycled precipitation (RP). Evapotranspiration (ET) estimated by the atmospheric–terrestrial water balance method (A–T) was employed to investigate precipitation recycling. Statistically, there was a turning point in 2002 for the rate in irrigated area increase, from 0.07 × 106 ha/year before 2002–0.217 × 106 ha/year after 2002. There were significant shifts in ET , PRR, and RP in NWC, using the turning point of irrigated area expansion as the line of demarcation. The contribution of the change in irrigated area to PRR increased from 18.3% (1982–2002) to 22.9% (2003–2018) in NWC. Prior to 2002, enhanced RP offset the increased ET by 72.9%. After 2002, the positive effect of irrigated area expansion on precipitation recycling disappeared in NWC. Due to the different climate and irrigation practices at the province level, the variations in irrigated area and their contributions to PRR were examined in three provinces, Xinjiang, Gansu, and Shaanxi. Results based on the Brubaker model and Budyko framework indicate that in Xinjiang and Gansu, the contribution of the irrigated area change after the turning point to PRR were 24.5% and -95.6%, respectively, and there is no potential for continued expansion of irrigated area. In Shaanxi, however, there is potential for continued expansion of irrigated area. The methodology for quantifying the impact of irrigated area change on PRR provides reliable references for the sustainable use of cultivated land and the protection of agricultural water resources. • Enhanced recycled precipitation offset ET increase induced by irrigated area expansion before 2002 in Northwest China. • Irrigated area in Northwest China exceeded the threshold and had the opposite effect on precipitation recycling ratio after 2002. • There is potential for continued expansion of the irrigated area in Shaanxi. [ABSTRACT FROM AUTHOR]

Irrigation is a prerequisite for the sustainable development of agricultural production. With the existing of water resources shortage and climate change, it is of great importance to explore the variation of crop irrigation water requirement (IWR) in the Yellow River Basin (YRB). Based on 1974–2017 meteorological dataset from 96 stations, we analyzed the spatio-temporal variation characteristics of meteorological factors and crop IWR during the growing seasons of four main crops including spring wheat, winter wheat, spring maize and summer maize, respectively. Furthermore, we explored the dominant meteorological factors of the crop IWR variation. The results indicated that daily mean temperature (T) had a significant upward trend, while the effective precipitation (P eff) did not change significantly during the growing season of each crop in the past 44 years. Crop IWR had increasing trend with 9.9 mm/decade, 4.3 mm/decade, 6.4 mm/decade for spring wheat, winter wheat, spring maize respectively, while a slight decreasing trend with − 1.7 mm/decade for summer maize. It is noted that extremely significant increase in crop IWR were mostly located in Ningxia, southern Gansu and eastern Qinghai. Moreover, P eff , net radiation (R n) and relative humidity (RH) were identified as the dominant meteorological factors influencing variations of IWR for all crops. In the context of significant increase in T and uncertain future precipitation patterns, IWR for spring wheat, winter wheat and spring maize in the YRB has shown an upward trend which is not favorable to the sustainable development of water resources. It is urgent to take effective water-saving measures to hedge the adverse impact of climate change on agriculture. These findings can provide scientific basis for rational allocation of agricultural water resources in the YRB. • Irrigation water requirements of main crops in the Yellow River Basin were quantitatively evaluated. • The spatio-temporal variation of meteorological factors during the crop growing seasons was investigated. • The spatial distribution and changing trend of crop irrigation water requirements were characterized. • The dominant meteorological factors of crop irrigation water requirements variation were found out. • It is urgent to take effective water-saving measures to hedge the adverse impact of climate change on agriculture. [ABSTRACT FROM AUTHOR]