A group of scientists says it has now reconstructed the history of the planet’s sea levels arcing back over some 3,000 years — leading it to conclude that the rate of increase experienced in the 20th century was “extremely likely” to have been faster than during nearly the entire period.
“We can say with 95 percent probability that the 20th-century rise was faster than any of the previous 27 centuries,” said Bob Kopp, a climate scientist at Rutgers University who led the research with nine colleagues from several U.S. and global universities. Kopp said it’s not that seas rose faster before that – they probably didn’t – but merely that the ability to say as much with the same level of confidence declines.
The study was published Monday in the Proceedings of the National Academy of Sciences.
Seas rose about 14 centimeters (5.5 inches) from 1900 to 2000, the new study suggests, for a rate of 1.4 millimeters per year. The current rate, according to NASA, is 3.4 millimeters per year, suggesting that sea level rise is still accelerating.Of course, for the True Believers, this is bad news. But as the Weather Underground site points out:
Well over seventy percent of our planet is covered by water. This was not always the case. During the last ice age, massive ice sheets covered portions of the northern and southern hemispheres (Figure 1). When the massive ice sheets melted, they released the water locked inside them – enough to make the seas rise by about 120m (390 ft) (Waelbroeck et al., 2002; Schneider von Deimling, et al., 2006; Rahmstorf, 2007).A very interesting discussion of the different causes of rise. As the 3/28/2009 Daily Telegraph points out:
But if there is one scientist who knows more about sea levels than anyone else in the world it is the Swedish geologist and physicist Nils-Axel Mörner, formerly chairman of the INQUA International Commission on Sea Level Change. And the uncompromising verdict of Dr Mörner, who for 35 years has been using every known scientific method to study sea levels all over the globe, is that all this talk about the sea rising is nothing but a colossal scare story.
Despite fluctuations down as well as up, "the sea is not rising," he says. "It hasn't risen in 50 years." If there is any rise this century it will "not be more than 10cm (four inches), with an uncertainty of plus or minus 10cm". And quite apart from examining the hard evidence, he says, the elementary laws of physics (latent heat needed to melt ice) tell us that the apocalypse conjured up by Al Gore and Co could not possibly come about.
The reason why Dr Mörner, formerly a Stockholm professor, is so certain that these claims about sea level rise are 100 per cent wrong is that they are all based on computer model predictions, whereas his findings are based on "going into the field to observe what is actually happening in the real world". \
When running the International Commission on Sea Level Change, he launched a special project on the Maldives, whose leaders have for 20 years been calling for vast sums of international aid to stave off disaster. Six times he and his expert team visited the islands, to confirm that the sea has not risen for half a century. Before announcing his findings, he offered to show the inhabitants a film explaining why they had nothing to worry about. The government refused to let it be shown.
Similarly in Tuvalu, where local leaders have been calling for the inhabitants to be evacuated for 20 years, the sea has if anything dropped in recent decades. The only evidence the scaremongers can cite is based on the fact that extracting groundwater for pineapple growing has allowed seawater to seep in to replace it. Meanwhile, Venice has been sinking rather than the Adriatic rising, says Dr Mörner.
One of his most shocking discoveries was why the IPCC has been able to show sea levels rising by 2.3mm a year. Until 2003, even its own satellite-based evidence showed no upward trend. But suddenly the graph tilted upwards because the IPCC's favoured experts had drawn on the finding of a single tide-gauge in Hong Kong harbour showing a 2.3mm rise. The entire global sea-level projection was then adjusted upwards by a "corrective factor" of 2.3mm, because, as the IPCC scientists admitted, they "needed to show a trend".