2026-03-30 東京大学
火山噴火に対する翌夏の水循環の応答
ドットは統計的に有意な領域を表す。四角は南アジアおよび北東アジアの領域を表す。
＜関連情報＞
- https://www.t.u-tokyo.ac.jp/press/pr2026-03-30-002
- https://www.nature.com/articles/s41467-026-70710-x
熱帯火山活動が地球規模の遠隔相関を介してアジア全域のモンスーン干ばつを引き起こす Tropical volcanism triggers pan-Asian monsoon droughts via circumglobal teleconnection
Wenzheng Nie,Jun Xia,Kanon Kino,Dunxian She & Taikan Oki
Nature Communications Published:30 March 2026
DOI:https://doi.org/10.1038/s41467-026-70710-x
Abstract
Explosive tropical volcanic eruptions can trigger widespread hydroclimate anomalies across Eurasia, yet the underlying dynamical pathways remain poorly understood. Here we show that large tropical eruptions consistently induce concurrent summer droughts over South Asia and northern East Asia during the past millennium, as revealed by proxy records and climate model simulations. Volcanically induced suppression of monsoon convection over South Asia reduces diabatic heating, exciting a Rossby wave response resembling the negative phase of the circumglobal teleconnection (CGT). This upper-tropospheric anomaly, robust across tropical ocean states, promotes northerly winds and strong subsidence that suppress rainfall over northern East Asia. The CGT-like teleconnection is robustly reproduced across tree-ring-based CGT reconstructions, last-millennium climate simulations, and idealized modeling experiments. Our findings identify a previously underappreciated volcanic–CGT–drought linkage, offering insights into the predictability of continental-scale climate anomalies under external forcing.
