Fig. 4: Future changes in the Madden-Julian Oscillation (MJO) circulation structure and background mean states.

Composites of the mass-weighted integral of the 1000–850-hPa 20–70-day moisture convergence (shading, units: mm day⁻¹) and the 850-hPa winds (vectors, units: m s⁻¹) associated with the MJO events in (a) historical (1979–2014) and b SSP5-8.5 (2064–2099) scenarios based on the MME12. c The difference between the two scenarios, with shading and vectors showing the values with the sign agreed by ≥ 66% of the models. The box region west of the MJO centroid (denoted by a blue dot) refers to the region where the Rossby westerlies (RW) are averaged, while the east of it indicates the region where the Kelvin easterlies (KE) are averaged. d–f Similar to panels a–c, but for the background 3-month running mean 1000–500-hPa MSE (units: 10⁸J m⁻²). The tropical Indian Ocean (20°S–10°N, 50°–110°E) and western-central Pacific Ocean (20°S–10°N, 110°E–150°W) where the MJO convective activity prevailing are outlined in black, with the value showing the regional mean.