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Is Global Sea Level Responding as Predicted by Climate Models?

Paper Reviewed
Parker, A. 2014. Present contributions to sea level rise by thermal expansion and ice melting and implications on coastal management. Ocean & Coastal Management 98: 202-211.

Parker (2014) begins his most interesting paper by stating "it is claimed that thermal expansion and ice melting from global warming significantly contribute to sea level rise." In fact, he notes that the IPCC (2014) report says "it is virtually certain that the upper ocean (above 700 m) has warmed from 1971-2010, and likely that it has warmed from the 1870s to 1971," as well as between depths of 700 and 2000 m from 1957 to 2009. In addition, he writes that in the opinion of the IPCC, "it is likely that the ocean warmed from 3000 m to the bottom from 1992 to 2005." But are these several contentions correct?

In light of ARGO (Array for Realtime Geostrophic Oceanography) data that are available for the last decade but do not yet cover the deepest ocean layers (below 2000 m) that contain half of the world's ocean waters, as well as areas poleward of 60°N and 60°S latitudes, Parker writes that "there is basically no significant warming or change of salinity within the accuracy limits of the measurements," leading him to contend that "the lack of any significant difference in the spatial distribution in latitude, longitude and depth from one year to another year shows that the theoretically proposed increased heat is missing."

More specifically, the Australian researcher reports that (1) the ocean temperature changes derived from models "are in striking contrast with the measurements by ARGO," that (2) "the huge increase of the heat content of the 0-700 and 0-2000 m depth water layer derived from models is not confirmed by the Argo measurements that show an almost flat temperature over the same layers," that over the last 11-year Sun-spot cycle, (3) "the sea ice extent has been increasing," (4) "the surface air temperatures have been cooling," and (5,6) "the ocean salinities and temperatures have changed minimally," that (7) "over the last 11 years there has been no increasing heat uptake of the oceans," that (8) "sea levels have not risen by the thermal expansion effect or the melting of ice," and that (9,10) "true measurements conflict with theoretically derived ocean temperatures and sea level changes."

And thus it is made clear that all of these real-world measurements, as Parker rightly notes, are in "conflict with theoretically derived ocean temperatures and sea level changes."

So who you gonna trust? ... the models or the measurements?

Posted 24 April 2015