NIWA climate scientist Dr James Renwick explains what's unique about the Antarctic/Southern Ocean climate system, the forces that influence it, and how it's changing.
He explains the influences of the Southern Annular Mode, El Niño Southern Oscillation (ENSO), ozone hole and global warming on the position of strong westerly winds in the Southern Hemisphere. These phenomena have a major impact on New Zealand's climate. Over the last 30 to 40 years, interactions between them have pushed the main belt of strong westerly winds towards Antarctica.