Increasing Heat Pile‐Up Events in the Southeast Indian Ocean Linked to Multi‐Year La Niña Conditions

Abstract The southeast Indian Ocean (SEIO) has witnessed amplifying variability in the 0–700 m heat content during the past decades. More heat pile‐up (HPU) events have been observed than before, leading to increased occurrence of marine heatwaves and threats to local marine ecosystems. Here, we sho...

Full description

Saved in:
Bibliographic Details
Main Authors: Yuanlong Li, Jing Duan, Yilong Lyu, Rui Li, Zhanxian Cui, Fan Wang
Format: Article
Language:English
Published: Wiley 2025-07-01
Series:Geophysical Research Letters
Subjects:
Online Access:https://doi.org/10.1029/2025GL116678
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850075319412719616
author Yuanlong Li
Jing Duan
Yilong Lyu
Rui Li
Zhanxian Cui
Fan Wang
author_facet Yuanlong Li
Jing Duan
Yilong Lyu
Rui Li
Zhanxian Cui
Fan Wang
author_sort Yuanlong Li
collection DOAJ
description Abstract The southeast Indian Ocean (SEIO) has witnessed amplifying variability in the 0–700 m heat content during the past decades. More heat pile‐up (HPU) events have been observed than before, leading to increased occurrence of marine heatwaves and threats to local marine ecosystems. Here, we show that most of these HPU events cooccur with multi‐year La Niña (MLN) conditions, and Pacific‐origin downwelling baroclinic waves play a key role in establishing the upper‐layer convergence of the SEIO. However, model experiments and budget analysis for the recent 2020–2023 event reveal that the extra heat in the SEIO is fueled mostly by the heat redistribution over the Indian Ocean, rather than by the Pacific via the Indonesian Throughflow (ITF). Climate models project more HPU events in the SEIO in future, partly associated with the increasing MLN events in a warming climate.
format Article
id doaj-art-beb09a4b1eb148b086273b9b8e918d96
institution DOAJ
issn 0094-8276
1944-8007
language English
publishDate 2025-07-01
publisher Wiley
record_format Article
series Geophysical Research Letters
spelling doaj-art-beb09a4b1eb148b086273b9b8e918d962025-08-20T02:46:20ZengWileyGeophysical Research Letters0094-82761944-80072025-07-015214n/an/a10.1029/2025GL116678Increasing Heat Pile‐Up Events in the Southeast Indian Ocean Linked to Multi‐Year La Niña ConditionsYuanlong Li0Jing Duan1Yilong Lyu2Rui Li3Zhanxian Cui4Fan Wang5Key Laboratory of Ocean Observation and Forecasting and Key Laboratory of Ocean Circulation and Waves Institute of Oceanology Chinese Academy of Sciences Qingdao ChinaKey Laboratory of Ocean Observation and Forecasting and Key Laboratory of Ocean Circulation and Waves Institute of Oceanology Chinese Academy of Sciences Qingdao ChinaKey Laboratory of Ocean Observation and Forecasting and Key Laboratory of Ocean Circulation and Waves Institute of Oceanology Chinese Academy of Sciences Qingdao ChinaKey Laboratory of Ocean Observation and Forecasting and Key Laboratory of Ocean Circulation and Waves Institute of Oceanology Chinese Academy of Sciences Qingdao ChinaKey Laboratory of Ocean Observation and Forecasting and Key Laboratory of Ocean Circulation and Waves Institute of Oceanology Chinese Academy of Sciences Qingdao ChinaKey Laboratory of Ocean Observation and Forecasting and Key Laboratory of Ocean Circulation and Waves Institute of Oceanology Chinese Academy of Sciences Qingdao ChinaAbstract The southeast Indian Ocean (SEIO) has witnessed amplifying variability in the 0–700 m heat content during the past decades. More heat pile‐up (HPU) events have been observed than before, leading to increased occurrence of marine heatwaves and threats to local marine ecosystems. Here, we show that most of these HPU events cooccur with multi‐year La Niña (MLN) conditions, and Pacific‐origin downwelling baroclinic waves play a key role in establishing the upper‐layer convergence of the SEIO. However, model experiments and budget analysis for the recent 2020–2023 event reveal that the extra heat in the SEIO is fueled mostly by the heat redistribution over the Indian Ocean, rather than by the Pacific via the Indonesian Throughflow (ITF). Climate models project more HPU events in the SEIO in future, partly associated with the increasing MLN events in a warming climate.https://doi.org/10.1029/2025GL116678ocean heat contentsoutheast Indian OceanLa Niñaclimate change
spellingShingle Yuanlong Li
Jing Duan
Yilong Lyu
Rui Li
Zhanxian Cui
Fan Wang
Increasing Heat Pile‐Up Events in the Southeast Indian Ocean Linked to Multi‐Year La Niña Conditions
Geophysical Research Letters
ocean heat content
southeast Indian Ocean
La Niña
climate change
title Increasing Heat Pile‐Up Events in the Southeast Indian Ocean Linked to Multi‐Year La Niña Conditions
title_full Increasing Heat Pile‐Up Events in the Southeast Indian Ocean Linked to Multi‐Year La Niña Conditions
title_fullStr Increasing Heat Pile‐Up Events in the Southeast Indian Ocean Linked to Multi‐Year La Niña Conditions
title_full_unstemmed Increasing Heat Pile‐Up Events in the Southeast Indian Ocean Linked to Multi‐Year La Niña Conditions
title_short Increasing Heat Pile‐Up Events in the Southeast Indian Ocean Linked to Multi‐Year La Niña Conditions
title_sort increasing heat pile up events in the southeast indian ocean linked to multi year la nina conditions
topic ocean heat content
southeast Indian Ocean
La Niña
climate change
url https://doi.org/10.1029/2025GL116678
work_keys_str_mv AT yuanlongli increasingheatpileupeventsinthesoutheastindianoceanlinkedtomultiyearlaninaconditions
AT jingduan increasingheatpileupeventsinthesoutheastindianoceanlinkedtomultiyearlaninaconditions
AT yilonglyu increasingheatpileupeventsinthesoutheastindianoceanlinkedtomultiyearlaninaconditions
AT ruili increasingheatpileupeventsinthesoutheastindianoceanlinkedtomultiyearlaninaconditions
AT zhanxiancui increasingheatpileupeventsinthesoutheastindianoceanlinkedtomultiyearlaninaconditions
AT fanwang increasingheatpileupeventsinthesoutheastindianoceanlinkedtomultiyearlaninaconditions