Recent Trends in the Recurrence of North Atlantic Atmospheric Circulation Patterns

Figure 3

(a) Four weather regimes of SLP in JJA (negative phase of the NAO, Atlantic Ridge, Scandinavian Blocking, Atlantic Low). The isolines have increments of 2 hPa. (b) Trends in atmospheric persistence for JJA. Vertical colored lines: frequency of dominating weather regime. The color is associated with a weather regime (NAO−: black; AR: red; BLO: green; AT: blue). Gray dotted line: linear trend of regime frequencies. Continuous back lines: frequency of dominating network in the summer. Dashed black lines: linear trend of dominating network frequency.

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