Critique of “Global sea level linked to global temperature,” by Vermeer and Rahmstorf

I was highly critical of Stefan Rahmstorf’s 2007 attempt to scare the world about sea level rise. He claimed that any temperature rise would result in an increase in the sea level rise rate that would take a millenium to dampen out. I pointed out at the time that this claim was contradicted by the very data that he used.

Now, Martin Vermeer and Rahmstorf (referred to as “VR2009” for the rest of this article) have given it another try in their 2009 PNAS paper, “Global sea level linked to global temperature”  (referred to as “VR2009” in this series of posts).  They have added another term, dT/dt which they say “corresponds to a sea-level response that can be regarded as ‘instantaneous.'”

This series of posts considers some of the bizarre consequences that would result if VR2009 were correct.  These unrealistic results necessarily lead to the rejection of VR2009

Part 1, The basic problem.

Part 2, A little more detail on the math.

Part 3, A few examples that show some bizarre consequences that would result if Vermeer’s and Rahmstorf’s model were correct.

Part 4, Improbable parallel universes.

Part 5, Variation of gamma.  Fast increasing temperatures cause sea level rise rate to drop, while slowly increasing temperatures cause sea level rise rates to increase.

A look at Church and White sea level data.  This is the sea level data that is the foundation of VR2009.

Response to RealClimate comments.  A few poorly considered comments concerning this series about VR2009 showed up at RealClimate.  This is my response.

Chao’s artificial reservoir “correction” to sea level.  This “correction” to Church and White’s sea level data leads to a (supposed) larger sea level rise during the 20th century.  But this “correction” has some critical flaws.

Part 6, Vermeer’s and Rahmstorf’s model is applied to satellite sea level data and fails the test.

Part 6.5,  the gory mathematical details from part 6.

Part 7  What does Vermeer’s and Rahmstorf’s model imply for a constant sea level rise rate of 3 mm/year?

Part 8, My reproduction of Vermeer’s and Rahmstor’s results

25% of sea level rise rate is due to groundwater depletion, not global warming.  Yet Vermeer and Rahmstorf did not correct their model for this effect.

Part 9,  What happens when Vermeer’s and Rahmstof’s model is applied to the updated Church and White sea level data with a Wada groundwater depletion correction?  The effect is huge

Part 10, Vermeer and Rahmstorf used out-dated sea level data from Church and White, and did not correct for groundwater depletion.  When Church’s and White’s updated sea level data is used and a groundwater depletion correction is incorporated, then their model yields 21st century sea level rises that are only half of what Vermeer and Rahmstorf reported.

Part 11.  Here is Vermeer’s and Rahmstorf’s Matlab source code.

Part 12. Vermeer and Rahmstorf claimed to apply a sea level correction based on Chao’s artificial reservoir data.  Instead, they use an inverse tangent function that hardly resembles Chao’s data.

Part 13.  Vermeer and Rahmstorf applied their model to IPCC temperature scenarios for the 21st century.  But here are some hypothetical 21st century temperature scenarios the bring out the bizarre effects of VR2009.

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