The monthly sensible heat flux calculation data of 74 conventional meteorological stations in Northwestern China, the monthly precipitation data of 155 conventional meteorological stations in the northwest of China, and the monthly average reanalysis data of NCEP/NCAR from 1961 to 2015 were selected. Mathematical statistical analysis methods such as empirical orthogonal function decomposition (EOF), linear regression analysis, and singular value decomposition (SVD) were used to analyze relationship between the anomalous temporal and spatial evolution characteristics of precipitation in midsummer (July-August) in the eastern part of Northwest China and the surface sensible heat anomalies in the early spring (March-April) of the Northwestern China. The results show that:(1) The precipitation in the eastern part of Northwestern China decreases from southeast to northwest with an overall decadal decline. The most obvious areas for reduction are northern Ningxia and central and southern Inner Mongolia. Its spatial anomaly is mainly characterized by a consistent increase (decrease) in the whole region and a "-+-" change in the northwest-southeast direction. (2) When the surface sensible heat flux is relatively strong (weak) in the early spring in Northwestern China, in midsummer (July-August), the height field over the southern part of Baikal Lake and northern China during midsummer is abnormally high (low), the water vapor divergence (convergence) in Northwestern China is strengthened, and the precipitation in the Ningxia Plain in the northwestern part of the northwest is abnormally low (above average); while in the southwest of Shaanxi, the convergence (diverging) of water vapor is strengthened, which is (not) conducive to the occurrence of precipitation in this region.
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