JpGU-AGU Joint Meeting 2020

講演情報

[E] ポスター発表

セッション記号 A (大気水圏科学) » A-OS 海洋科学・海洋環境

[A-OS23] Atlantic climate variability, and its global impacts and predictability

コンビーナ:Ingo Richter(JAMSTEC Japan Agency for Marine-Earth Science and Technology)、時長 宏樹(九州大学応用力学研究所)、Andrea Taschetto(University of New South Wales)、Noel S Keenlyside(Geophysical Institute Bergen)

[AOS23-P04] The extraordinary Atlantic Nino of 2019/2020

*Ingo Richter1 (1.JAMSTEC Japan Agency for Marine-Earth Science and Technology)

キーワード:equatorial Atlantic, Atlantic Nino, global warming

From December 2019 onward there was an increase in equatorial Atlantic sea-surface temperatures (SST), with anomalous warming in the eastern part of the basin. While such interannual warm events (also known as Atlantic Ninos) are a common occurrence in the region, the 2019/2020 event stands out for two reasons: 1) It is the warmest event to occur in at least two decades, thereby punctuating a period of relatively low variability in the equatorial Atlantic. 2) Its timing was unusual, as Atlantic Niños almost exclusively develop in boreal spring and peak in summer.
Here we analyze SST, surface winds, surface heat fluxes, and sea-surface height to explain the unusual development of the 2019/2020 event. Preliminary results suggest that it was primarily driven by surface heat fluxes rather than by ocean dynamics. We further attempt to put this event into the context of previous studies that have argued for a decrease of equatorial Atlantic variability in recent decades.