Increased El Niño-Southern Oscillation variability under greenhouse warming and the impact on Antarctic ice sheet melt and Southern Ocean warming

• Main Author: Cai, W.
• Format: Conference Object
• Language: English
• Published: 2023
• Subjects: Antarctic; Southern Ocean; Antarc*; Ice Sheet; Sea ice
• Online Access: https://gfzpublic.gfz-potsdam.de/pubman/item/item_5018910

Sea surface temperature (SST) variability of El Niño-Southern Oscillation (ENSO) underpins its global impact. Future change of ENSO SST variability is a long-standing science issue. In its sixth assessment, the Intergovernmental Panel on Climate Change reports no systematic change in ENSO and IOD SST under any emission scenarios considered. However, comparison in a century-long period between the 20th and 21st century shows a robust increase in ENSO and IOD SST variability in some plausible scenarios, with substantial impacts. For example, the increase in ENSO SST variability leads to a reduced Southern Ocean midlatitude warming, an accelerated warming in Antarctic shelf ocean, but a slowed Antarctic sea ice reduction. An increase in ENSO variability leading to a slower intensification of circum-Antarctic warm upwelling is responsible for these impacts.