New Study Reveals Estimates of Sea Level Rise May be Too Conservative

During the last interglacial period, over 100,000 years ago, the world’s oceans were over four meters (app. 13 feet) higher than they are today. That’s the conclusion reached by scientists in a newly published article in the journal Nature Geoscience. The article is available free of charge upon registration at: http://www.nature.com/ngeo/journal/vaop/ncurrent/abs/ngeo.2007.28.html.

“The last interglacial period, Marine Isotope Stage (MIS) 5e, was characterized by global mean surface temperatures that were at least 2 °C [3.6°F] warmer than present, the authors noted. “Mean sea level stood 4-6 meters [13 to 20 feet] higher than modern sea level [citations] with an important contribution from a reduction of the Greenland ice sheet [citations].”

The researchers used fossil reef data, described as a study using “a combination of a continuous high-resolution sea-level record, based on the stable oxygen isotopes of planktonic foraminifera from the central Red Sea [citations], and age constraints from coral data to estimate rates of sea-level change during MIS-5e.”

Their findings indicate that “sea-level fluctuations of up to 10 meters [around 33 feet] around the mean [citations]” occurred during the period. But the report indicates that, “so far it has not been possible to constrain the duration and rates of change of these shorter-term variations.”

The study projected “average rates of sea-level rise of 1.6 meters [around 5.2 feet] per century.” From that data, the study concludes: “As global mean temperatures during MIS-5e were comparable to projections for future climate change under the influence of anthropogenic greenhouse-gas emissions [citations], these observed rates of sea-level change inform the ongoing debate about high versus low rates of sea-level rise in the coming century [citations].”

While the report may be taken as a conjecture of abstract science, it is nonetheless informative as to what the future may hold. There’s nothing abstract for the insurance industry, if sea levels rise at the rates indicated. Low lying areas, such as New York, London, Tokyo and Miami, would all experience serious flooding, the cost of which could well be beyond the industry’s capacity to bear.

Source: Nature Geoscience Journal