Fig. 1: Increasing heatwave trends over the midlatitudes and Europe.
From: Accelerated western European heatwave trends linked to more-persistent double jets over Eurasia

a Decadal trends in heatwave frequency (days/decade) and b heatwave cumulative intensity (°C/decade) for July-August 1979–2020. c Probability density distributions of decadal trends of heatwave frequency of all land grid points for Europe (in dark red, as the region included in the dashed box of (a, b): 35–70°N and 10oW-50°E) and the midlatitudes (20–70°N) excluding Europe (in blue) and d probability density distributions of decadal trends of heatwave cumulative intensity. The mean trend for each distribution is shown with dashed vertical lines and provided on the top right of the panels. The continuous vertical lines correspond to 0 (i.e. no trend). The two distributions were compared for each case with a Kolmogorov-Smirnov test (p values shown on the center-right).