资源环境科技发展态势分析平台

Changes to the Southern Hemisphere (SH) surface westerlies fundamentally control regional patterns of air temperature, storm tracks and precipitation, while also regulating ocean circulation, heat transport and carbon uptake. Wind‐forced ocean perturbation experiments commonly apply idealized poleward wind shifts ranging between 0.5 – 10 degrees of latitude, and wind intensification factors of between 10 – 300%. In addition, changes in winds are often prescribed ad‐hoc as a zonally uniform anomaly and can neglect important seasonal differences. Here we quantify historical and projected SH westerly wind changes based on examination of CMIP5, CMIP6 and reanalysis data. We find a significant reduction in the location bias in CMIP6 and an associated reduction in the projected poleward shift compared to CMIP5. Under a high emission scenario, we find a projected end of 21^st Century ensemble mean wind increase of ∼10% and a poleward shift of ∼0.8° latitude, although there are important seasonal and regional variations.