1
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Li D, DeConto RM, Pollard D, Hu Y. Competing climate feedbacks of ice sheet freshwater discharge in a warming world. Nat Commun 2024; 15:5178. [PMID: 38890359 PMCID: PMC11189430 DOI: 10.1038/s41467-024-49604-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 06/05/2024] [Indexed: 06/20/2024] Open
Abstract
Freshwater discharge from ice sheets induces surface atmospheric cooling and subsurface ocean warming, which are associated with negative and positive feedbacks respectively. However, uncertainties persist regarding these feedbacks' relative strength and combined effect. Here we assess associated feedbacks in a coupled ice sheet-climate model, and show that for the Antarctic Ice Sheet the positive feedback dominates in moderate future warming scenarios and in the early stage of ice sheet retreat, but is overwhelmed by the negative feedback in intensive warming scenarios when the West Antarctic Ice Sheet undergoes catastrophic collapse. The Atlantic Meridional Overturning Circulation is affected by freshwater discharge from both the Greenland and the Antarctic ice sheets and, as an interhemispheric teleconnection bridge, exacerbates the opposing ice sheet's retreat via the Bipolar Seesaw. These results highlight the crucial role of ice sheet-climate interactions via freshwater flux in future ice sheet retreat and associated sea-level rise.
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Affiliation(s)
- Dawei Li
- Key Laboratory of Polar Ecosystem and Climate Change, Ministry of Education, and School of Oceanography, Shanghai Jiao Tong University, Shanghai, 200030, China.
- Shanghai Frontiers Science Center of Polar Science, Shanghai Jiao Tong University, Shanghai, 200030, China.
- Key Laboratory for Polar Science, Polar Research Institute of China, Ministry of Natural Resources, Shanghai, 200136, China.
| | - Robert M DeConto
- Department of Earth, Geographic, and Climate Sciences, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - David Pollard
- Department of Earth, Geographic, and Climate Sciences, University of Massachusetts Amherst, Amherst, MA, 01003, USA
- Earth and Environmental Systems Institute, Pennsylvania State University, University Park, PA, 16802, USA
| | - Yongyun Hu
- Laboratory for Climate and Ocean-Atmosphere Studies, Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, 100871, Beijing, China
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2
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Watanabe M, Kang SM, Collins M, Hwang YT, McGregor S, Stuecker MF. Possible shift in controls of the tropical Pacific surface warming pattern. Nature 2024; 630:315-324. [PMID: 38867130 DOI: 10.1038/s41586-024-07452-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 04/16/2024] [Indexed: 06/14/2024]
Abstract
Changes in the sea surface temperature (SST) pattern in the tropical Pacific modulate radiative feedbacks to greenhouse gas forcing, the pace of global warming and regional climate impacts. Therefore, elucidating the drivers of the pattern is critically important for reducing uncertainties in future projections. However, the causes of observed changes over recent decades, an enhancement of the zonal SST contrast coupled with a strengthening of the Walker circulation, are still debated. Here we focus on the role of external forcing and review existing mechanisms of the forced response categorized as either an energy perspective that adopts global and hemispheric energy budget constraints or a dynamical perspective that examines the atmosphere-ocean coupled processes. We then discuss their collective and relative contributions to the past and future SST pattern changes and propose a narrative that reconciles them. Although definitive evidence is not yet available, our assessment suggests that the zonal SST contrast has been dominated by strengthening mechanisms in the past, but will shift towards being dominated by weakening mechanisms in the future. Finally, we present opportunities to resolve the model-observations discrepancy regarding the recent trends.
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Affiliation(s)
- Masahiro Watanabe
- Atmosphere and Ocean Research Institute, University of Tokyo, Kashiwa, Japan.
| | - Sarah M Kang
- Max Planck Institute for Meteorology, Hamburg, Germany.
| | - Matthew Collins
- Department of Mathematics and Statistics, University of Exeter, Exeter, UK
| | - Yen-Ting Hwang
- Department of Atmospheric Sciences, National Taiwan University, Taipei, Taiwan
| | - Shayne McGregor
- School of Earth, Atmosphere and Environment, Monash University, Melbourne, Victoria, Australia
| | - Malte F Stuecker
- Department of Oceanography & International Pacific Research Center (IPRC), School of Ocean and Earth Science and Technology (SOEST), University of Hawai'i at Mānoa, Honolulu, HI, USA
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3
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Cheng C, Jenkins A, Holland PR, Wang Z, Dong J, Liu C. Ice shelf basal channel shape determines channelized ice-ocean interactions. Nat Commun 2024; 15:2877. [PMID: 38570489 PMCID: PMC10991488 DOI: 10.1038/s41467-024-47351-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 03/25/2024] [Indexed: 04/05/2024] Open
Abstract
Growing evidence has confirmed the critical role played by basal channels beneath Antarctic ice shelves in both ice shelf stability and freshwater input to the surrounding ocean. Here we show, using a 3D ice shelf-ocean boundary current model, that deeper basal channels can lead to a significant amplification in channelized basal melting, meltwater channeling, and warming and salinization of the channel flow. All of these channelized quantities are also modulated by channel width, with the level of modulation determined by channel height. The explicit quantification of channelized basal melting and the meltwater transport in terms of channel cross-sectional shape is potentially beneficial for the evaluation of ice shelf mass balance and meltwater contribution to the nearshore oceanography. Complicated topographically controlled circulations are revealed to be responsible for the unique thermohaline structure inside deep channels. Our study emphasizes the need for improvement in observations of evolving basal channels and the hydrography inside them, as well as adjacent to the ice front where channelized meltwater emerges.
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Affiliation(s)
- Chen Cheng
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519080, China.
| | - Adrian Jenkins
- Department of Geography and Environmental Sciences, Faculty of Engineering and Environment, Northumbria University, Newcastle upon Tyne, NE1 8ST, UK
| | | | - Zhaomin Wang
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519080, China
| | - Jihai Dong
- School of Marine Sciences, Nanjing University of Information Science and Technology, Nanjing, 210044, China
| | - Chengyan Liu
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519080, China
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4
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Fletcher C, Ripple WJ, Newsome T, Barnard P, Beamer K, Behl A, Bowen J, Cooney M, Crist E, Field C, Hiser K, Karl DM, King DA, Mann ME, McGregor DP, Mora C, Oreskes N, Wilson M. Earth at risk: An urgent call to end the age of destruction and forge a just and sustainable future. PNAS NEXUS 2024; 3:pgae106. [PMID: 38566756 PMCID: PMC10986754 DOI: 10.1093/pnasnexus/pgae106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Human development has ushered in an era of converging crises: climate change, ecological destruction, disease, pollution, and socioeconomic inequality. This review synthesizes the breadth of these interwoven emergencies and underscores the urgent need for comprehensive, integrated action. Propelled by imperialism, extractive capitalism, and a surging population, we are speeding past Earth's material limits, destroying critical ecosystems, and triggering irreversible changes in biophysical systems that underpin the Holocene climatic stability which fostered human civilization. The consequences of these actions are disproportionately borne by vulnerable populations, further entrenching global inequities. Marine and terrestrial biomes face critical tipping points, while escalating challenges to food and water access foreshadow a bleak outlook for global security. Against this backdrop of Earth at risk, we call for a global response centered on urgent decarbonization, fostering reciprocity with nature, and implementing regenerative practices in natural resource management. We call for the elimination of detrimental subsidies, promotion of equitable human development, and transformative financial support for lower income nations. A critical paradigm shift must occur that replaces exploitative, wealth-oriented capitalism with an economic model that prioritizes sustainability, resilience, and justice. We advocate a global cultural shift that elevates kinship with nature and communal well-being, underpinned by the recognition of Earth's finite resources and the interconnectedness of its inhabitants. The imperative is clear: to navigate away from this precipice, we must collectively harness political will, economic resources, and societal values to steer toward a future where human progress does not come at the cost of ecological integrity and social equity.
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Affiliation(s)
- Charles Fletcher
- School of Ocean and Earth Science and Technology, University of Hawai‘i at Mānoa, Honolulu, HI 96822, USA
| | - William J Ripple
- Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR 97331, USA
| | - Thomas Newsome
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW 2006, Australia
| | - Phoebe Barnard
- Center for Environmental Politics and School of Interdisciplinary Arts and Sciences, University of Washington, Seattle, WA 98195, USA
- African Climate and Development Initiative and FitzPatrick Institute, University of Cape Town, Cape Town 7700, South Africa
| | - Kamanamaikalani Beamer
- Hui ‘Āina Momona Program, Richardson School of Law, University of Hawai‘i at Mānoa, Honolulu, HI 96822, USA
- Hawai‘inuiākea School of Hawaiian Knowledge, Kamakakūokalani Center for Hawaiian Studies, University of Hawai‘i at Mānoa, Honolulu, HI 96822, USA
| | - Aishwarya Behl
- School of Ocean and Earth Science and Technology, University of Hawai‘i at Mānoa, Honolulu, HI 96822, USA
| | - Jay Bowen
- Institute of American Indian Arts, Santa Fe, NM 87508, USA
- Upper Skagit Tribe, Sedro Woolley, WA 98284, USA
| | - Michael Cooney
- School of Ocean and Earth Science and Technology, Hawai‘i Natural Energy Institute, University of Hawai‘i at Mānoa, Honolulu, HI 96822, USA
| | - Eileen Crist
- Department of Science Technology and Society, Virginia Tech, Blacksburg, VA 24060, USA
| | - Christopher Field
- Doerr School for Sustainability, Stanford Woods Institute for the Environment, Stanford University, Stanford, CA 94305, USA
| | - Krista Hiser
- Department of Languages, Linguistics, and Literature, Kapi‘olani Community College, Honolulu, HI 96816, USA
- Global Council for Science and the Environment, Washington, DC 20006, USA
| | - David M Karl
- Department of Oceanography, School of Ocean and Earth Science and Technology, Honolulu, HI 96822, USA
- Daniel K. Inouye Center for Microbial Oceanography, Research and Education, University of Hawai‘i at Mānoa, Honolulu, HI 96822, USA
| | - David A King
- Department of Chemistry, University of Cambridge, Cambridge CB2 1DQ, UK
| | - Michael E Mann
- Department of Earth and Environmental Science, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Davianna P McGregor
- Department of Ethnic Studies, Center for Oral History, University of Hawai‘i at Mānoa, Honolulu, HI 96822, USA
| | - Camilo Mora
- Department of Geography and Environment, University of Hawai‘i at Mānoa, Honolulu, HI 96822, USA
| | - Naomi Oreskes
- Department of the History of Science, Harvard University, Cambridge, MA 02138, USA
| | - Michael Wilson
- Associate Justice, Hawaii Supreme Court (retired), Honolulu, HI 96813, USA
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5
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Han X, Stewart AL, Chen D, Janout M, Liu X, Wang Z, Gordon AL. Circum-Antarctic bottom water formation mediated by tides and topographic waves. Nat Commun 2024; 15:2049. [PMID: 38448416 PMCID: PMC10918180 DOI: 10.1038/s41467-024-46086-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 02/14/2024] [Indexed: 03/08/2024] Open
Abstract
The downslope plumes of dense shelf water (DSW) are critical for the formation of Antarctic Bottom Water (AABW), and thus to the exchange of heat and carbon between surface and abyssal ocean. Previous studies have shown that tides and overflow-forced topographic Rossby waves (TRWs) may have strong impact on the downslope transport of DSW, but it remains unclear how the combined action of these two processes influence the descent processes of DSW, and of the resulting AABW properties. Here, with a synthesis of historical in situ observations and a set of numerical model experiments, we show that tides and TRWs play comparable roles in AABW formation: they both act to accelerate DSW descent to the abyss, leading to the formation of colder and denser AABW. Yet, tides have little impact on AABW formation unless the continental slope is steep enough to suppress TRW generation. We further characterize the dynamical regimes of dense overflows around the entire Antarctic continent based on the relative importance of TRWs versus tides. These findings highlight the pervasive role of high-frequency processes, which are not well represented in the present climate models, in the formation of AABW, and thus in the global overturning circulation.
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Affiliation(s)
- Xianxian Han
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
- School of Atmospheric Sciences, Sun Yat-sen University, Zhuhai, China
| | - Andrew L Stewart
- Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles, CA, USA
| | - Dake Chen
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China.
- School of Atmospheric Sciences, Sun Yat-sen University, Zhuhai, China.
- State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China.
| | - Markus Janout
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
| | - Xiaohui Liu
- State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China
| | - Zhaomin Wang
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
| | - Arnold L Gordon
- Lamont Doherty Earth Observatory, Columbia University, Palisades, NY, USA
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6
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Liu H, Zheng W, Gao Y, Yang L, Yue F, Huang T, Xie Z. Increased Contribution of Circumpolar Deep Water Upwelling to Methylmercury in the Upper Ocean around Antarctica: Evidence from Mercury Isotopes in the Ornithogenic Sediments. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:2762-2773. [PMID: 38294849 DOI: 10.1021/acs.est.3c06923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
Upwelling plays a pivotal role in supplying methylmercury (MeHg) to the upper oceans, contributing to the bioaccumulation of MeHg in the marine food web. However, the influence of the upwelling of Circumpolar Deep Water (CDW), the most voluminous water mass in the Southern Ocean, on the MeHg cycle in the surrounding oceans and marine biota of Antarctica remains unclear. Here, we study the mercury (Hg) isotopes in an ornithogenic sedimentary profile strongly influenced by penguin activity on Ross Island, Antarctica. Results indicate that penguin guano is the primary source of Hg in the sediments, and the mass-independent isotope fractionation of Hg (represented by Δ199Hg) can provide insights on the source of marine MeHg accumulated by penguin. The Δ199Hg in the sediments shows a significant decrease at ∼1550 CE, which is primarily attributed to the enhanced upwelling of CDW that brought more MeHg with lower Δ199Hg from the deeper seawater to the upper ocean. We estimate that the contribution of MeHg from the deeper seawater may reach more than 38% in order to explain the decline in Δ199Hg at ∼1550 CE. Moreover, we found that the intensified upwelling may have increased the MeHg exposure for marine organisms, highlighting the importance of CDW upwelling on the MeHg cycle in Antarctic coastal ecosystems.
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Affiliation(s)
- Hongwei Liu
- Department of Environmental Science and Engineering, Anhui Key Laboratory of Polar Environment and Global Change, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Wang Zheng
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
- School of Earth and Space Exploration, Arizona State University, Tempe, Arizona 85287, United States
| | - Yuesong Gao
- Department of Environmental Science and Engineering, Anhui Key Laboratory of Polar Environment and Global Change, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Lianjiao Yang
- Department of Environmental Science and Engineering, Anhui Key Laboratory of Polar Environment and Global Change, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Fange Yue
- Department of Environmental Science and Engineering, Anhui Key Laboratory of Polar Environment and Global Change, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Tao Huang
- School of Resources and Environmental Engineering, Anhui University, Hefei, Anhui 230601, China
| | - Zhouqing Xie
- Department of Environmental Science and Engineering, Anhui Key Laboratory of Polar Environment and Global Change, University of Science and Technology of China, Hefei, Anhui 230026, China
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7
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Miller UK, Zappa CJ, Gordon AL, Yoon ST, Stevens C, Lee WS. High Salinity Shelf Water production rates in Terra Nova Bay, Ross Sea from high-resolution salinity observations. Nat Commun 2024; 15:373. [PMID: 38228621 PMCID: PMC10791653 DOI: 10.1038/s41467-023-43880-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Accepted: 11/22/2023] [Indexed: 01/18/2024] Open
Abstract
High Salinity Shelf Water (HSSW) formed in the Ross Sea of Antarctica is a precursor to Antarctic Bottom Water (AABW), a water mass that constitutes the bottom limb of the global overturning circulation. HSSW production rates are poorly constrained, as in-situ observations are scarce. Here, we present high-vertical-and-temporal-resolution salinity time series collected in austral winter 2017 from a mooring in Terra Nova Bay (TNB), one of two major sites of HSSW production in the Ross Sea. We calculate an annual-average HSSW production rate of ~0.4 Sv (106 m3 s-1), which we use to ground truth additional estimates across 2012-2021 made from parametrized net surface heat fluxes. We find sub-seasonal and interannual variability on the order of [Formula: see text] [Formula: see text], with a strong dependence on variability in open-water area that suggests a sensitivity of TNB HSSW production rates to changes in the local wind regime and offshore sea ice pack.
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Affiliation(s)
- Una Kim Miller
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York, USA.
| | - Christopher J Zappa
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York, USA
| | - Arnold L Gordon
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York, USA
| | | | - Craig Stevens
- National Institute of Water and Atmospheric Research, Wellington, New Zealand
- University of Auckland, Auckland, New Zealand
| | - Won Sang Lee
- Korea Polar Research Institute, Incheon, South Korea
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8
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Sutherland WJ, Bennett C, Brotherton PNM, Butchart SHM, Butterworth HM, Clarke SJ, Esmail N, Fleishman E, Gaston KJ, Herbert-Read JE, Hughes AC, James J, Kaartokallio H, Le Roux X, Lickorish FA, Newport S, Palardy JE, Pearce-Higgins JW, Peck LS, Pettorelli N, Primack RB, Primack WE, Schloss IR, Spalding MD, Ten Brink D, Tew E, Timoshyna A, Tubbs N, Watson JEM, Wentworth J, Wilson JD, Thornton A. A horizon scan of global biological conservation issues for 2024. Trends Ecol Evol 2024; 39:89-100. [PMID: 38114339 DOI: 10.1016/j.tree.2023.11.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 10/30/2023] [Accepted: 11/07/2023] [Indexed: 12/21/2023]
Abstract
We present the results of our 15th horizon scan of novel issues that could influence biological conservation in the future. From an initial list of 96 issues, our international panel of scientists and practitioners identified 15 that we consider important for societies worldwide to track and potentially respond to. Issues are novel within conservation or represent a substantial positive or negative step-change with global or regional extents. For example, new sources of hydrogen fuel and changes in deep-sea currents may have profound impacts on marine and terrestrial ecosystems. Technological advances that may be positive include benchtop DNA printers and the industrialisation of approaches that can create high-protein food from air, potentially reducing the pressure on land for food production.
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Affiliation(s)
- William J Sutherland
- Conservation Science Group, Department of Zoology, Cambridge University, The David Attenborough Building, Pembroke Street, Cambridge CB2 3QZ, UK.
| | - Craig Bennett
- Royal Society of Wildlife Trusts, The Kiln, Waterside, Mather Road, Newark, Nottinghamshire NG24 1WT, UK
| | | | - Stuart H M Butchart
- Conservation Science Group, Department of Zoology, Cambridge University, The David Attenborough Building, Pembroke Street, Cambridge CB2 3QZ, UK; Birdlife International, The David Attenborough Building, Pembroke Street, Cambridge CB2 3QZ, UK
| | - Holly M Butterworth
- Natural Resources Wales, Cambria House, 29 Newport Road, Cardiff CF24 0TP, UK
| | | | - Nafeesa Esmail
- Wilder Institute, 1300 Zoo Road NE, Calgary, AB T2E 7V6, Canada
| | - Erica Fleishman
- College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR 97331, USA
| | - Kevin J Gaston
- Environment and Sustainability Institute, University of Exeter, Penryn, Cornwall TR10 9FE, UK
| | | | - Alice C Hughes
- School of Biological Sciences, University of Hong Kong, Hong Kong Special Administrative Region of China, China
| | - Jennifer James
- The Environment Agency, Horizon House, Deanery Road, Bristol BS1 5TL, UK
| | | | - Xavier Le Roux
- Microbial Ecology Centre, Université Lyon 1, INRAE, CNRS, UMR 1418, 69622 Villeurbanne, France
| | - Fiona A Lickorish
- UK Research and Consultancy Services (RCS) Ltd, Valletts Cottage, Westhope, Hereford HR4 8BU, UK
| | - Sarah Newport
- UK Research and Innovation, Natural Environment Research Council, Polaris House, North Star Avenue, Swindon SN2 1EU, UK
| | - James E Palardy
- The Pew Charitable Trusts, 901 East Street NW, Washington, DC 20004, USA
| | - James W Pearce-Higgins
- Conservation Science Group, Department of Zoology, Cambridge University, The David Attenborough Building, Pembroke Street, Cambridge CB2 3QZ, UK; British Trust for Ornithology, The Nunnery, Thetford, Norfolk IP24 2PU, UK
| | - Lloyd S Peck
- British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge CB3 0ET, UK
| | - Nathalie Pettorelli
- Institute of Zoology, Zoological Society of London, Regent's Park, London NW1 4RY, UK
| | | | | | - Irene R Schloss
- Instituto Antártico Argentino, Buenos Aires, Argentina; Centro Austral de Investigaciones Científicas (CADIC-CONICET), Ushuaia, Argentina; Universidad Nacional de Tierra del Fuego, Ushuaia, Argentina
| | - Mark D Spalding
- Conservation Science Group, Department of Zoology, Cambridge University, The David Attenborough Building, Pembroke Street, Cambridge CB2 3QZ, UK; The Nature Conservancy, Department of Physical, Earth, and Environmental Sciences, University of Siena, Pian dei Mantellini, Siena 53100, Italy
| | - Dirk Ten Brink
- Wetlands International, 6700 AL Wageningen, The Netherlands
| | - Eleanor Tew
- Conservation Science Group, Department of Zoology, Cambridge University, The David Attenborough Building, Pembroke Street, Cambridge CB2 3QZ, UK; Forestry England, 620 Bristol Business Park, Coldharbour Lane, Bristol BS16 1EJ, UK
| | - Anastasiya Timoshyna
- TRAFFIC, The David Attenborough Building, Pembroke Street, Cambridge CB2 3QZ, UK
| | - Nicolas Tubbs
- WWF-Belgium, Boulevard Emile Jacqmainlaan 90, 1000 Brussels, Belgium
| | - James E M Watson
- School of The Environment, University of Queensland, St Lucia, QLD 4072, Australia
| | - Jonathan Wentworth
- Parliamentary Office of Science and Technology, 14 Tothill Street, Westminster, London SW1H 9NB, UK
| | - Jeremy D Wilson
- RSPB Centre for Conservation Science, 2 Lochside View, Edinburgh EH12 9DH, UK
| | - Ann Thornton
- Conservation Science Group, Department of Zoology, Cambridge University, The David Attenborough Building, Pembroke Street, Cambridge CB2 3QZ, UK
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9
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Li Z, England MH, Groeskamp S. Recent acceleration in global ocean heat accumulation by mode and intermediate waters. Nat Commun 2023; 14:6888. [PMID: 37898610 PMCID: PMC10613216 DOI: 10.1038/s41467-023-42468-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 10/12/2023] [Indexed: 10/30/2023] Open
Abstract
The ocean absorbs >90% of anthropogenic heat in the Earth system, moderating global atmospheric warming. However, it remains unclear how this heat uptake is distributed by basin and across water masses. Here we analyze historical and recent observations to show that ocean heat uptake has accelerated dramatically since the 1990s, nearly doubling during 2010-2020 relative to 1990-2000. Of the total ocean heat uptake over the Argo era 2005-2020, about 89% can be found in global mode and intermediate water layers, spanning both hemispheres and both subtropical and subpolar mode waters. Due to anthropogenic warming, there are significant changes in the volume of these water-mass layers as they warm and freshen. After factoring out volumetric changes, the combined warming of these layers accounts for ~76% of global ocean warming. We further decompose these water-mass layers into regional water masses over the subtropical Pacific and Atlantic Oceans and in the Southern Ocean. This shows that regional mode and intermediate waters are responsible for a disproportionate fraction of total heat uptake compared to their volume, with important implications for understanding ongoing ocean warming, sea-level rise, and climate impacts.
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Affiliation(s)
- Zhi Li
- Climate Change Research Centre, University of New South Wales, Sydney, NSW, 2052, Australia.
- Australian Centre for Excellence in Antarctic Science, University of New South Wales, Sydney, NSW, 2052, Australia.
- Centre for Marine Science and Innovation (CMSI), University of New South Wales, Sydney, NSW, 2052, Australia.
| | - Matthew H England
- Australian Centre for Excellence in Antarctic Science, University of New South Wales, Sydney, NSW, 2052, Australia
- Centre for Marine Science and Innovation (CMSI), University of New South Wales, Sydney, NSW, 2052, Australia
| | - Sjoerd Groeskamp
- NIOZ Royal Netherlands Institute for Sea Research, Department of Ocean Systems, 1790 AB, Den Burg, Texel, The Netherlands
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10
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Davison BJ, Hogg AE, Gourmelen N, Jakob L, Wuite J, Nagler T, Greene CA, Andreasen J, Engdahl ME. Annual mass budget of Antarctic ice shelves from 1997 to 2021. SCIENCE ADVANCES 2023; 9:eadi0186. [PMID: 37824617 DOI: 10.1126/sciadv.adi0186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 09/07/2023] [Indexed: 10/14/2023]
Abstract
Antarctic ice shelves moderate the contribution of the Antarctic Ice Sheet to global sea level rise; however, ice shelf health remains poorly constrained. Here, we present the annual mass budget of all Antarctic ice shelves from 1997 to 2021. Out of 162 ice shelves, 71 lost mass, 29 gained mass, and 62 did not change mass significantly. Of the shelves that lost mass, 68 had statistically significant negative mass trends, 48 lost more than 30% of their initial mass, and basal melting was the dominant contributor to that mass loss at a majority (68%). At many ice shelves, mass losses due to basal melting or iceberg calving were significantly positively correlated with grounding line discharge anomalies; however, the strength and form of this relationship varied substantially between ice shelves. Our results illustrate the utility of partitioning high-resolution ice shelf mass balance observations into its components to quantify the contributors to ice shelf mass change and the response of grounded ice.
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Affiliation(s)
| | - Anna E Hogg
- School of Earth and Environment, University of Leeds, Leeds, UK
| | - Noel Gourmelen
- School of Geosciences, University of Edinburgh, Edinburgh, UK
- Earthwave, Codebase, Office L2, 3 Lady Lawson St, Edinburgh, UK
| | - Livia Jakob
- Earthwave, Codebase, Office L2, 3 Lady Lawson St, Edinburgh, UK
| | - Jan Wuite
- ENVEO IT GmbH, Innsbruck 6020, Austria
| | | | - Chad A Greene
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Julia Andreasen
- Department of Soil, Water, and Climate, University of Minnesota, St. Paul, MN, USA
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