Fig. 5: Future Madden-Julian Oscillation (MJO) acceleration driven by the stronger effect of warming-induced atmospheric stabilization than moisture destabilization.
From: Shifts in MJO behavior enhance predictability of subseasonal precipitation whiplashes
Scatter plots showing the relationship of the mean MJO propagation speed (\({C}_{{MJO}}\), units: m s−1) against (a) the coupled Rossby-Kelvin (R-K) ratio (unitless) and b the regional mean-state moist gravity wave (GW) speed (\({C}_{1},\) units: m s−1) averaged over 10°S–10°N, 50°–150°E based on 28 CMIP6 models. The regression is estimated using Sen’s slope. The equation and the Kendall rank correlation coefficient are shown on the bottom left. c A bar plot showing the effects of static stability (SS) and moisture destabilization (MD) on the future change of moist GW speed (\(\Delta {C}_{1}\)) (units: m s−1) averaged in 10°S–10°N, 50°–150°E during the SSP5-8.5 (2064–2099) scenario, compared to the historical run (1979–2014). The quantities are computed based on the background 3-month running mean fields (see Methods), with the central month being the month of day 0 of each MJO event. The MME12 mean value and the percentage change with respect to the historical regional mean \({C}_{1}\) (41.35 m s−1) are shown, with the uncertainties representing the inter-model spread from the 25th to 75th percentile of the values output by the 12 good models.
