John Lyman, an oceanographer at NOAA's Joint Institute for Marine and Atmospheric Research,   led an international team of scientists that analyzed nine different estimates of heat content in the upper ocean from 1993 to 2008.  The Argo profile data were used to calibrate the older data and show that the warming signal can be discerned as six times larger than noise estimates.  The researchers claim the warming of 0.16 degree C, is 80% of the excess heat captured by greenhouse gas effect in the past 16 years.  It may not sound like much, but due to the high heat capacity of water and the vast size of the ocean it corresponds the amount of heat from "Five-hundred 100-watt light bulbs per person on earth burning continuously - that would be the trend we've seen over the last 16 years just being sucked up by the ocean." (J. Lyman)..... 

Read more on NOAA News or Radio Australia and Comments in Nature. 

Kevin E. Trenberth reports in Nature that "The warming ocean is revealed by changes in heat content from 1993 to 2008, shown by the black line with error bars, as constructed by Lyman et al.¹. This analysis samples the ocean to 700 m depth and gives an average warming trend of 0.64 W m⁻² (red line). The data available from Argo floats since 2003 enable an estimate to 2,000 m depth (blue line)⁸ to be made. The differences between the black and blue plots after 2003 suggest that there has been significant warming below 700 m, and that rates of warming have slowed in recent years. Processing of the two data sets is not compatible, however, so firm conclusions cannot yet be drawn by comparing them."