ENSO affects the North Atlantic Oscillation 1 year later

• 成果类型: Article
• 署名作者: Scaife, Adam A.; Dunstone, Nick; Hardiman, Steven; Ineson, Sarah; Li, Chaofan; Lu, Riyu; Pang, Bo; Klein-Tank, Albert; Smith, Doug; Van Niekerk, Annelize; Renwick, James; Williams, Ned
• 署名单位: Met Office - UK; Hadley Centre; University of Exeter; Chinese Academy of Sciences; Institute of Atmospheric Physics, CAS; European Centre for Medium-Range Weather Forecasts (ECMWF); Victoria University Wellington; Max Planck Society
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-8946
• DOI: 10.1126/science.adk4671
• 发表日期: 2024-10-04
• 页码: 82-86
• 关键词: atmospheric variability; climate; stratosphere; teleconnections; propagation; mechanisms; IMPACT; MODEL

摘要

We demonstrate a 1-year lagged extratropical response to the El Ni & ntilde;o-Southern Oscillation (ENSO) in observational analyses and climate models. The response maps onto the Arctic Oscillation and is strongest in the North Atlantic, where it resembles the North Atlantic Oscillation (NAO). Unexpectedly, these 1-year lagged teleconnections are at least as strong as the better-known simultaneous winter connections. However, the 1-year lagged response is opposite in sign to the simultaneous response such that 1 year later, El Ni & ntilde;o is followed by a positive NAO, whereas La Ni & ntilde;a is followed by a negative NAO. The lagged response may also interfere with simultaneous ENSO teleconnections. We show here that these effects are unlikely to be caused by residual aliasing of ENSO cycles; rather, slowly migrating atmospheric angular momentum anomalies explain both the sign and the timing of the extratropical response. Our results have implications for understanding ENSO teleconnections, explaining observed extratropical climate variability and interpreting seasonal to interannual climate predictions.