EGU23-14931, updated on 20 May 2024
https://doi.org/10.5194/egusphere-egu23-14931
EGU General Assembly 2023
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.

New improvements for monitoring the Ocean Heat Content and the Earth Energy imbalance (MOHeaCAN).

Florence Marti1, Alejandro Blazquez2, Benoit Meyssignac2, Michaël Ablain1, Anne Barnoud1, Robin Fraudeau1, Victor Rousseau1, Jonathan Chenal3, Gilles Larnicol1, Julia Pfeffer1, Marco Restano4, Jérôme Benveniste5, Gérald Dibarboure6, and Francois Bignalet-Cazalet6
Florence Marti et al.
  • 1MAGELLIUM, Ramonville Saint-Agne, France
  • 2LEGOS, Université de Toulouse, CNES, CNRS, UPS, IRD, Toulouse, France
  • 3Institut national de l'information géographique et forestière, Toulouse, France
  • 4SERCO/ESRIN, Frascati, Italy
  • 5ESA/ESRIN, Frascati, Italy
  • 6CNES, Toulouse, France

The Earth energy imbalance (EEI) at the top of the atmosphere is responsible for the accumulation of energy in the climate system. While necessary to better understand the Earth’s warming climate, measuring the EEI is challenging as it is a globally integrated variable whose variations are small (0.5-1 W.m−2) compared to the amount of energy entering and leaving the climate system (~ 340 W.m-2). Accuracies better than 0.1 W.m−2 are needed to evaluate the temporal variations of the EEI at decadal and longer time-scales. The CERES experiment provides EEI time variations with a typical uncertainty of ± 0.1 W.m−2 and shows a trend in EEI of 0.50 +/- 0.47 W.m−2 per decade over the period 2005-2019.

The combination of space altimetry and space gravimetry measurements provides an estimate of the ocean heat content (OHC) change which is an accurate proxy of EEI (because >90% of the excess of energy stored by the planet in response to the EEI is accumulated in the ocean in the form of heat). 

In Marti et al. (2021), the global OHC was estimated at global scales based on the combination of space altimetry and space gravimetry measurements over 2002-2016. Changes in the EEI were then derived with realistic estimates of its uncertainty.

Here we present the improvements brought to the global OGC and EEI over an extended period (2002-2021), such as the calculation of the expansion efficiency of heat over the total water column, the improvement of ocean mass solution, the empirical correction of the wet tropospheric correction of Jason-3 altimeter measurements (Barnoud et al., 2022).

The space geodetic GOHC-EEI product based on space altimetry and space gravimetry is available on the AVSIO website at https://doi.org/10.24400/527896/a01-2020.003.

 

References:

Barnoud A., Picard B., Meyssignac B., Marti F., Ablain M., Roca R. Reducing the uncertainty in the satellite altimetry estimates of global mean sea level trends using highly stable water vapour climate data records. Submitted to JGR: Oceans.

Marti, F., Blazquez, A., Meyssignac, B., Ablain, M., Barnoud, A., Fraudeau, R., Jugier, R., Chenal, J., Larnicol, G., Pfeffer, J., Restano, M., and Benveniste, J.: Monitoring the ocean heat content change and the Earth energy imbalance from space altimetry and space gravimetry, Earth Syst. Sci. Data, 14, 229–249, https://doi.org/10.5194/essd-14-229-2022, 2022.



How to cite: Marti, F., Blazquez, A., Meyssignac, B., Ablain, M., Barnoud, A., Fraudeau, R., Rousseau, V., Chenal, J., Larnicol, G., Pfeffer, J., Restano, M., Benveniste, J., Dibarboure, G., and Bignalet-Cazalet, F.: New improvements for monitoring the Ocean Heat Content and the Earth Energy imbalance (MOHeaCAN)., EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-14931, https://doi.org/10.5194/egusphere-egu23-14931, 2023.