Heat stored in the Earth system 1960–2020: where does the energy go?
Authors: von Schuckmann Karina , Minière Audrey , Gues Flora , Cuesta-Valero Francisco José , Kirchengast Gottfried , Adusumilli Susheel , Straneo Fiammetta , Ablain Michaël , Allan Richard P. , Barker Paul M. , Beltrami Hugo , Blazquez Alejandro , Boyer Tim , Cheng Lijing , Church John , Desbruyeres Damien , Dolman Han , Domingues Catia M. , García-García Almudena , Giglio Donata , Gilson John E. , Gorfer Maximilian , Haimberger Leopold , Hakuba Maria Z. , Hendricks Stefan , Hosoda Shigeki , Johnson Gregory C. , Killick Rachel , King Brian , Kolodziejczyk Nicolas , Korosov Anton , Krinner Gerhard , Kuusela Mikael , Landerer Felix W. , Langer Moritz , Lavergne Thomas , Lawrence Isobel , Li Yuehua , Lyman John , Marti Florence , Marzeion Ben , Mayer Michael , MacDougall Andrew H. , McDougall Trevor , Monselesan Didier Paolo , Nitzbon Jan , Otosaka Inès , Peng Jian , Purkey Sarah , Roemmich Dean , Sato Kanako , Sato Katsunari , Savita Abhishek , Schweiger Axel , Shepherd Andrew , Seneviratne Sonia I. , Simons Leon , Slater Donald A. , Slater Thomas , Steiner Andrea K. , Suga Toshio , Szekely Tanguy , Thiery Wim , Timmermans Mary-Louise , Vanderkelen Inne , Wjiffels Susan E. , Wu Tonghua , Zemp Michael 
Published: April 2023

Abstract. The Earth climate system is out of energy balance, and heat has
accumulated continuously over the past decades, warming the ocean, the land,
the cryosphere, and the atmosphere. According to the Sixth Assessment Report
by Working Group I of the Intergovernmental Panel on Climate Change,
this planetary warming over multiple decades is human-driven and results in
unprecedented and committed changes to the Earth system, with adverse
impacts for ecosystems and human systems. The Earth heat inventory provides
a measure of the Earth energy imbalance (EEI) and allows for quantifying
how much heat has accumulated in the Earth system, as well as where the heat is
stored. Here we show that the Earth system has continued to accumulate
heat, with 381±61 ZJ accumulated from 1971 to 2020. This is equivalent to a
heating rate (i.e., the EEI) of 0.48±0.1 W m−2. The majority,
about 89 %, of this heat is stored in the ocean, followed by about 6 %
on land, 1 % in the atmosphere, and about 4 % available for melting
the cryosphere. Over the most recent period (2006–2020), the EEI amounts to
0.76±0.2 W m−2. The Earth energy imbalance is the most
fundamental global climate indicator that the scientific community and the
public can use as the measure of how well the world is doing in the task of
bringing anthropogenic climate change under control. Moreover, this
indicator is highly complementary to other established ones like global mean
surface temperature as it represents a robust measure of the rate of climate
change and its future commitment. We call for an implementation of the
Earth energy imbalance into the Paris Agreement's Global Stocktake based on
best available science. The Earth heat inventory in this study, updated from
von Schuckmann et al. (2020), is underpinned by worldwide multidisciplinary
collaboration and demonstrates the critical importance of concerted
international efforts for climate change monitoring and community-based
recommendations and we also call for urgently needed actions for enabling
continuity, archiving, rescuing, and calibrating efforts to assure improved
and long-term monitoring capacity of the global climate observing system. The data for the Earth heat inventory are publicly available, and more details are provided in Table 4.