Cheng, Lijing, Trenberth, Kevin E., Palmer, Matthew D., Zhu, Jiang, Abraham, John P.

Ocean Science Discussions

Published date April 8, 2016

Observed and simulated full-depth ocean heat content changes for 1970–2005

  • States that greenhouse-gas emissions have created a planetary energy imbalance that is primarily manifested by increasing ocean heat content (OHC)
  • Presents updated observational estimates of full-depth OHC change since 1970 that account for recent advancements in reducing observation errors and biases
  • Finds the full-depth OHC has increased by 0.74 [0.68, 0.80] × 1022 J/yr (0.46 Wm−2) and 1.22 [1.16–1.29] ×1022 J/yr (0.75 Wm−2) for 1970-2005 and 1992-2005 respectively, with 5 % to 95 % confidence interval of the median
  • Finds the CMIP5 models show large spread in OHC changes, but the ensemble median has excellent agreement with the' observational estimate: 0.68 [0.54–0.82] × 1022 J/yr (0.41 Wm−2) from 1970 to 2005 and 1.25 [1.10–1.41] × 1022 J/yr (0.77 Wm−2) from 1992 to 2005
  • States these results increase confidence in both the observational and model estimates to quantify and study changes in Earth’s energy imbalance over the historical period
  • Suggests that OHC be a fundamental metric for climate model validation and evaluation