American Elephants


Could Global Warming Slow the Rise of the Sea Level? by The Elephant's Child

Since the first Planet of the Apes movie, the image of the Statue of Liberty drowning in rising sea waters has been done and done and overdone. But images are powerful and that may have helped to make many people think that a global rise in sea levels is the most to-be feared consequence of global warming. Flooding Pacific Islands, environmental refugees, panic in the streets. If I remember correctly, Santa Barbara was going to paint a line on city streets to indicate the potential rise of waters.

Remember that Obama predicted a deceleration of sea level rise when he accepted the Democratic Party nomination in 2008. “This was the moment when the rise of the oceans began to slow, and our planet began to heal.”  Some scientists have predicted an acceleration of ongoing global rise, while others insist stoutly that there has been no increase in the rise of sea level. Here is climate scientist S. Fred Singer to explain the complications.

The difficulty with projections of sea level rise is nicely illustrated by the IPCC. The initial estimates of its first assessment report (1990) showed a range of 10-367 cm for sea level rise in 2100. The second report published in 1996 narrowed the range to 3-124 cm. The third report published in 2001 showed 11-77 cm. The fourth assessment report published in 2007 showed 14-43 cm in draft form but changed it to 18-59 cm in the final printed version.  As can be seen, the maximum SLR decreased successively as estimates improved.  All these IPCC projections are very much smaller than the extreme values of about 600 cm (20 feet!) by activist-scientist James Hansen (and by climate multi-millionaire Al Gore) — which assume excessive melting of the Greenland icecaps.

If you pour yourself a glass of water and add some ice cubes, as the ice melts the glass does not overflow. Keep that in mind. If you add another handful of ice, the glass may overflow.

During the strong warming of 1920-1940 there was no SLR — indicating a rough balance between the opposing effects.  In fact, scrutinizing the record, I can even discern a slight lowering of sea level, an over-compensation.  Unfortunately, back then in 1997 we had no data on Antarctic ice accumulation; so the hypothesis was not publishable.  However, now we do have sufficient data in support of such a scenario.

But if, as surmised, ice accumulation roughly balances ocean thermal expansion and contributions from melting mountain glaciers, why then is sea level rising?  Another riddle requiring a solution.

The relevant clue comes from corals and from geological observations: It seems that sea level has been rising for the past centuries at about the same rate as seen by tidal gauges in the last 100 years.  In other words, sea level was rising even during the colder Little Ice age, from about 1400 to 1850 AD.  This provides further support for the hypothesis that the observed global SLR since 1900 is reasonably independent of the observed temperature rise.  [It is also a killing argument against a widely quoted (‘semi-empirical’) theory that assumes rate of SLR is proportional to global surface temperature.]

Dr. Singer concludes that the melting of the West Antarctic Ice Sheet, which is not floating ice but like a mountain glacier—contributes more water to the ocean thus raising the sea level by about 7 inches per century. The melting will continue for another several millennia until the ice sheet is all gone (barring another ice age in the meantime), and there is nothing that we can do to stop this future rise. It is as inevitable as the ocean tides. Do read the whole thing. You will become an expert, able to dispel the anxieties of the true believers, and  your own, if any. Learn how they measure, and how recent studies have clarified the picture. And no, even Obama’s valiant efforts had not the slightest effect.

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