Isolating the signal of ocean global warming
Article first published online: 6 DEC 2007
Copyright 2007 by the American Geophysical Union.
Geophysical Research Letters
Volume 34, Issue 23, December 2007
How to Cite
2007), Isolating the signal of ocean global warming, Geophys. Res. Lett., 34, L23610, doi:10.1029/2007GL031712., , , and (
- Issue published online: 6 DEC 2007
- Article first published online: 6 DEC 2007
- Manuscript Accepted: 29 OCT 2007
- Manuscript Received: 17 AUG 2007
 Identifying the signature of global warming in the world's oceans is challenging because low frequency circulation changes can dominate local temperature changes. The IPCC fourth assessment reported an average ocean heating rate of 0.21 ± 0.04 Wm−2 over the period 1961–2003, with considerable spatial, interannual and inter-decadal variability. We present a new analysis of millions of ocean temperature profiles designed to filter out local dynamical changes to give a more consistent view of the underlying warming. Time series of temperature anomaly for all waters warmer than 14°C show large reductions in interannual to inter-decadal variability and a more spatially uniform upper ocean warming trend (0.12 Wm−2 on average) than previous results. This new measure of ocean warming is also more robust to some sources of error in the ocean observing system. Our new analysis provides a useful addition for evaluation of coupled climate models, to the traditional fixed depth analyses.