Heat stored in the Earth system:where does the energy go?

• Published in: Earth System Science Data
• Main Authors: von Schuckmann, Karina, Cheng, Lijing, Palmer, Matthew D., Hansen, James, Tassone, Caterina, Aich, Valentin, Adusumilli, Susheel, Beltrami, Hugo, Boyer, Tim, Cuesta-Valero, Francisco Jose, Desbruyeres, Damien, Domingues, Catia, Garcia-Garcia, Almudena, Gentine, Pierre, Gilson, John, Gorfer, Maximilian, Haimberger, Leopold, Ishii, Masayoshi, Johnson, Gregory C., Killick, Rachel, King, Brian A., Kirchengast, Gottfried, Kolodziejczyk, Nicolas, Lyman, John, Marzeion, Ben, Mayer, Michael, Monier, Maeva, Monselesan, Didier Paolo, Purkey, Sarah, Roemmich, Dean, Schweiger, Axel, Seneviratne, Sonia, Shepherd, Andrew, Slater, Donald A., Steiner, Andrea K., Straneo, Fiammetta, Timmermans, Mary-Louise, Wijffels, Susan E.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2020
• Subjects: Sea-level rise; Surface temperature; GPS radio occultation; Global ocean; Climate-change; Mass-balance; Artic amplification; Southern ocean; North Atlantic; Ice discharge; Southern Ocean
• Online Access: https://risweb.st-andrews.ac.uk/portal/en/researchoutput/heat-stored-in-the-earth-system(a09e38ce-2230-44fe-a714-aac9baea9065).html; https://doi.org/10.5194/essd-12-2013-2020; https://research-repository.st-andrews.ac.uk/bitstream/10023/21568/1/von_Schuckmann_2020_ESED_heat_stored_CC.pdf

Human-induced atmospheric composition changes cause a radiative imbalance at the top of the atmosphere which is driving global warming. This Earth energy imbalance (EEI) is the most critical number defining the prospects for continued global warming and climate change. Understanding the heat gain of the Earth system - and particularly how much and where the heat is distributed - is fundamental to understanding how this affects warming ocean, atmosphere and land, rising surface temperature, sea level, and loss of grounded and floating ice, which are fundamental concerns for society. This study is a Global Climate Observing System (GCOS) concerted international effort to update the Earth heat inventory and presents an updated assessment of ocean warming estimates as well as new and updated estimates of heat gain in the atmosphere, cryosphere and land over the period 1960-2018. The study obtains a consistent long-term Earth system heat gain over the period 1971-2018, with a total heat gain of 358 +/- 37 ZJ, which is equivalent to a global heating rate of 0.47 +/- 0 .1 Wm(-2). Over the period 1971-2018 (2010-2018), the majority of heat gain is reported for the global ocean with 89% (90 %), with 52% for both periods in the upper 700m depth, 28% (30 %) for the 700-2000m depth layer and 9% (8 %) below 2000m depth. Heat gain over land amounts to 6% (5 %) over these periods, 4% (3 %) is available for the melting of grounded and floating ice, and 1% (2 %) is available for atmospheric warming. Our results also show that EEI is not only continuing, but also increasing. the EEI amounts to 0.87 +/- 0.12Wm(-2) during 2010-2018. Stabilization of climate, the goal of the universally agreed United Nations Framework Convention on Climate Change (UNFCCC) in 1992 and the Paris Agreement in 2015, requires that EEI be reduced to approximately zero to achieve Earth's system quasi-equilibrium. The amount of CO2 in the atmosphere would need to be reduced from 410 to 353 ppm to increase heat radiation to space by 0.87Wm(-2), bringing ...