Fig. 4: Spatial contributions of decadal oceanic variability to HWCIS and HWCIA.
From: Decadal oceanic variability amplified recent heatwave in the Northern Hemisphere
a Explained variance (R2) of decadal HWCIS in the Northern Hemisphere based on regression with decadal oceanic variability. c 2013–2021 linear trend in the time series of the decadal oceanic variability-induced HWCIS. b, d Same as a and c but for HWCIA. The time series of the decadal oceanic variability-induced HWCIS and HWCIA were calculated as the regression of the decadal components of HWCIS and HWCIA at each grid on the time series in Fig. 3a and Fig. S6 for 1942–2021. Significant regression coefficients at the 95% confidence level (two-sided P < 0.05), assessed with a random-phase resampling test55, are marked with dots.
