Arctic marine heatwaves forced by greenhouse gases and triggered by abrupt sea-ice melt

Abstract Since 2007, unprecedented marine heatwave events are occurring over the Arctic Ocean. Here we identify the fraction of the likelihood of Arctic marine heatwaves magnitude that is attributable to greenhouse gas forcing. Results reveal that Arctic marine heatwaves are primarily triggered by a...

Full description

Bibliographic Details
Main Authors: Armineh Barkhordarian, David M. Nielsen, Dirk Olonscheck, Johanna Baehr
Format: Article
Language:English
Published: Nature Portfolio 2024-02-01
Series:Communications Earth & Environment
Online Access:https://doi.org/10.1038/s43247-024-01215-y
_version_ 1827326049992572928
author Armineh Barkhordarian
David M. Nielsen
Dirk Olonscheck
Johanna Baehr
author_facet Armineh Barkhordarian
David M. Nielsen
Dirk Olonscheck
Johanna Baehr
author_sort Armineh Barkhordarian
collection DOAJ
description Abstract Since 2007, unprecedented marine heatwave events are occurring over the Arctic Ocean. Here we identify the fraction of the likelihood of Arctic marine heatwaves magnitude that is attributable to greenhouse gas forcing. Results reveal that Arctic marine heatwaves are primarily triggered by an abrupt sea-ice retreat, which coincides with the maximum downward radiative fluxes. Up to 82% of the sea surface temperature variability over the shallow Arctic marginal seas, where marine heatwaves are prone to occur, can be explained by net accumulation of seasonal surface heat flux in the ocean. Event attribution analysis demonstrates that the 103-day long 2020 event – the most intense (4 ∘C) recorded so far in the Arctic – would be exceptionally unlikely in the absence of greenhouse gas forcing in terms of both intensity and duration. Our further results imply that if greenhouse gas emissions continue to rise, along with the expansion of first-year ice extent, moderate marine heatwaves in the Arctic will very likely persistently reoccur.
first_indexed 2024-03-07T14:39:02Z
format Article
id doaj.art-aad3f4b2edaa4bb68f0296a10fcd8c05
institution Directory Open Access Journal
issn 2662-4435
language English
last_indexed 2024-03-07T14:39:02Z
publishDate 2024-02-01
publisher Nature Portfolio
record_format Article
series Communications Earth & Environment
spelling doaj.art-aad3f4b2edaa4bb68f0296a10fcd8c052024-03-05T20:27:50ZengNature PortfolioCommunications Earth & Environment2662-44352024-02-015111110.1038/s43247-024-01215-yArctic marine heatwaves forced by greenhouse gases and triggered by abrupt sea-ice meltArmineh Barkhordarian0David M. Nielsen1Dirk Olonscheck2Johanna Baehr3Institute of Oceanography, Center for Earth System Research and Sustainability (CEN), Universität HamburgInstitute of Oceanography, Center for Earth System Research and Sustainability (CEN), Universität HamburgMax Planck Institute for MeteorologyInstitute of Oceanography, Center for Earth System Research and Sustainability (CEN), Universität HamburgAbstract Since 2007, unprecedented marine heatwave events are occurring over the Arctic Ocean. Here we identify the fraction of the likelihood of Arctic marine heatwaves magnitude that is attributable to greenhouse gas forcing. Results reveal that Arctic marine heatwaves are primarily triggered by an abrupt sea-ice retreat, which coincides with the maximum downward radiative fluxes. Up to 82% of the sea surface temperature variability over the shallow Arctic marginal seas, where marine heatwaves are prone to occur, can be explained by net accumulation of seasonal surface heat flux in the ocean. Event attribution analysis demonstrates that the 103-day long 2020 event – the most intense (4 ∘C) recorded so far in the Arctic – would be exceptionally unlikely in the absence of greenhouse gas forcing in terms of both intensity and duration. Our further results imply that if greenhouse gas emissions continue to rise, along with the expansion of first-year ice extent, moderate marine heatwaves in the Arctic will very likely persistently reoccur.https://doi.org/10.1038/s43247-024-01215-y
spellingShingle Armineh Barkhordarian
David M. Nielsen
Dirk Olonscheck
Johanna Baehr
Arctic marine heatwaves forced by greenhouse gases and triggered by abrupt sea-ice melt
Communications Earth & Environment
title Arctic marine heatwaves forced by greenhouse gases and triggered by abrupt sea-ice melt
title_full Arctic marine heatwaves forced by greenhouse gases and triggered by abrupt sea-ice melt
title_fullStr Arctic marine heatwaves forced by greenhouse gases and triggered by abrupt sea-ice melt
title_full_unstemmed Arctic marine heatwaves forced by greenhouse gases and triggered by abrupt sea-ice melt
title_short Arctic marine heatwaves forced by greenhouse gases and triggered by abrupt sea-ice melt
title_sort arctic marine heatwaves forced by greenhouse gases and triggered by abrupt sea ice melt
url https://doi.org/10.1038/s43247-024-01215-y
work_keys_str_mv AT arminehbarkhordarian arcticmarineheatwavesforcedbygreenhousegasesandtriggeredbyabruptseaicemelt
AT davidmnielsen arcticmarineheatwavesforcedbygreenhousegasesandtriggeredbyabruptseaicemelt
AT dirkolonscheck arcticmarineheatwavesforcedbygreenhousegasesandtriggeredbyabruptseaicemelt
AT johannabaehr arcticmarineheatwavesforcedbygreenhousegasesandtriggeredbyabruptseaicemelt