Study Forecasts Sea Level Rise That Is 10X Actual Rise In Last Century

A recent study “Rapid Accumulation of Committed Sea-level Rise from Global Warming” asserts that some 1700 US cities and towns will be below sea level by 2100. The study was authored by Benjamin H Strauss for the Proceedings of the National Academy of Sciences.  The study is behind a paywall.  Dr Don J Easterbrook has reviewed the claim and he has spelled out his thinking in a Climate Depot posting. (Those views will constitute the body of this posting.)  Easterbrook says:

‘The accelerated rise is based on postulated accelerated warming but there has been no warming in the past 15 years and, in fact, the climate has cooled during that time. So no climatic warming means no accelerated sea level rise as postulated by Strauss…the huge rise of sea level rates proposed by Strauss are absurd and that the maximum sea level rise by 2100 will be less than one foot.”

Easterbrook says the sea level rate of rise used in Strauss’ study is more than 10 times the rate of sea level rise over the past century.   Easterbrook  adds these comments on the claims in that study:

“Twenty five percent of the populations of these 1,700 cities would be living below sea level by 2100 and 79 cities with a combined population of 835,000 would be submerged by 2023 and about half of the population of Fort Lauderdale, Hoboken, and Palm Beach would be submerged by 2023 according to Strauss. The basis for these amazing conclusions is apparently a 12 inch (222 cm) per decade rise of global sea level, the maximum IPCC estimate, which is postulated to be caused by increasing atmospheric CO2.

According to Strauss, Norfolk, Virginia, the largest naval base in the U.S., would be at risk by the 2040s and the Pentagon has already begun actively planning to relocate bases. Much of Miami would be under water by 2040 and half of Palm Beach, FL would be submerged by the 2060s.  Fort Lauderdale would be well below sea-level. About half the population of Cambridge, MA, across the Charles River from Boston would be submerged by the early 2060s”.

Easterbrook says the author has used the IPCC forecast maximum rate of rise to make the claim that by the 2100 sea level will have claimed the 1700 cities and towns.  In the chart below, Easterbrook, using the current rate of sea level rise, plots the rise in sea level from now to the end of this century. This is in contrast to the IPCC forecast (shown in red)  for that period of time.

(Y axis is mm of sea level rise and the X axis is years.)

Easterbrook says  “Two questions immediately arise: (1) what is going to cause such accelerated sea level rise and (2) where is all the water going to come from?”

Easterbrook concludes by saying:

” In order to get the accelerated sea level rise postulated by Strauss, much of the Greenland and Antarctic ice sheets would have to melt.  However the Antarctic ice cap is expanding, not melting and the Greenland ice cap was about the same size as at present during the Holocene Climatic Optimum. In addition, Morner (2011) has shown that the maximum possible eustatic sea level rate is only 10 mm year, (i.e., 1.0 m in a century).

The conclusion that we can draw from these data is that the huge rise of sea level rates proposed by Strauss are absurd and that the maximum sea level rise by 2100 will be less than one foot.”

cbdakota