Fig. 2: The interdecadal variations in the impact of the June NWPSH on the circulation.
From: The interdecadal variations of cross-month correlation feature of the NWPSH

a–c The regressions of the June NWPSH index onto the 850hPa geopotential height field (unit: \({\rm{gpm}}\)) for June, July, and August in 1979–2005. The purple box denotes the region for defining the NWPSH index. d–f are similar to (a–c), but for 2006-2024. Dots indicate significance at the 95% confidence level.