Antarctic extremes are important for regional climate change. The change of extreme indices show the period variation and regional variation with the outputs from CMIP6, and the warming of minimum temperature is faster than for the maximum temperature. The analysis of Antarctic extremes may be conducive to better understanding the distinct Antarctic climate.

Multifractal analysis, as a Chaos theory application, is a helpful tool for studying climatic variability and detecting changes in annual temperature and precipitation cycles. This paper studies the variability and trends in Northern Patagonia, Argentina, for 1981–2019. The results indicate a severe temperature rise in one sector of the Patagonian Andes mountain range and an alarming decrease in the rainfall regime in semiarid and arid sectors.

Our analysis of atmospheric data for the late austral winter season (June–September) reveals the existence of a new type of synoptic-scale atmospheric cyclones in the south-east tropical Indian Ocean (SETIO) comprising westerly wind events along the equator, suppressing equatorial upwelling, and north-westerly winds off Sumatra’s west coast, suppressing cold-water upwelling. Our analysis shows that the absence of cyclones concurs with the development of strong coastal upwelling off Sumatra, indicates that the absence or presence of cyclones is a driver of IOD variability.

In the Pacific, many communities are experiencing more frequent coastal flooding in the absence of heavy rainfall or strong winds. We quantify the observed and projected changes in such events, finding that threshold exceedances have increased in recent years at all locations, and daily exceedances may occur as early as 2080 according to high emissions scenario SSP5–8.5. Our results highlight the changing nature of coastal flood risk in the Pacific, with extreme weather becoming increasingly unnecessary for flooding to occur.

The Australian Bureau of Meteorology has upgraded its forecast capability for seasonal and multi-week timescales. The upgraded ACCESS-S system (version 2) introduces a new data assimilation functionality which is shown to increase the forecast accuracy of Australian climate and the El Niño–Southern Oscillation. ACCESS-S2 is now operational and providing climate outlooks to the general public.