Update October 2019
Global trend in OHC between 1991 and 2016 (DOHC) estimated from Atmospheric Potential Oxygen (APO) 

DOHC =  12.9 +/-  7.9 ZJ /y

Trend is an update based on Resplandy, L., Keeling, R.F., Eddebbar, Y., Brooks, M.K., Wang, R., Bopp, L., Long, M.C., Dunne, J.P., Koeve, W., Oschlies, A. Quantification of ocean heat uptake from changes in atmospheric O2 and CO2 composition. subm. to Nature Scientific Reports. 

Details:
- This estimate is representative of the ocean Full-depth.

- It relies on the ocean warming-driven changes observed in APO (DAPO_Climate) and a ratio that ties changes in APO_climate to changes in OHC (DAPO_Climate-to-DOHC) constrained from ocean observations and models.
DAPO_Climate-to-DOHC = 0.86 +/- 0.03 per meg per 10^22 

- Uncertainty in OHC includes uncertainties in:
 - APO measurements 
 - fossil fuel burning and cement production effects on APO
 - atmospheric deposition of nitrogen, phosphorus and iron effect on APO 
 - anthropogenic carbon ocean sink effect on APO
 - land oxidative ratio effect on APO
 - the APO_Climate-to-OHC ratio

- The data and code used to derive APO_Climate is available here: https://zenodo.org/record/2571986. (DOI:10.5281/zenodo.2571986)