Why the Increasing Trend of Summer Rainfall over North China Has Halted since the Mid-1990s

Figure 8

(a) Same as Figure 5 but for 200 hPa zonal winds (contours, unit: m/s) and temperature (shading, unit: °C). The difference of temperature in blue box with black dots is statistically significant at the 95% confidence level according to Student’s t-test. The difference of zonal winds with black cross is statistically significant at the 95% confidence level according to Student’s t-test. (b) 200 hPa zonal winds (unit: m/s) in JA of 1979–1996 mean (black contours) and 1997–2016 mean (white contours). The shading is the climatic mean of 200 hPa zonal winds during 1979–2016. The black box shows North China. The green box shows the region of Lake Baikal.

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