Sea Level Rising Faster Than Forecast

(November 24, Bloomberg) Greenland and Antarctic ice sheets are melting faster than expected and the future rise in sea level will be “much higher” than previously forecast, a group of 26 climate scientists said in a report today.


The rise in global sea level since 1995 has been 3.4 millimeters a year (0.13 inches), 80 percent greater than past predictions, said Richard Somerville, a professor at Scripps Institution of Oceanography in San Diego and a contributor to today’s report. Sea levels may rise 1 meter by 2100, double earlier forecasts, according to the report.

About half of the authors took part in a United Nations panel that in 2007 warned warming will cause water shortages to spread and droughts and floods to become more frequent. Today’s report includes three years of new observations, and fills in missing data such as the contribution of melting ice in Greenland and the Antarctic.

“Climate change is accelerating,” Somerville said in an interview. “It’s more severe than anticipated, and it’s occurring more rapidly than anticipated.”

The 2007 report from the Intergovernmental Panel on Climate Change said global warming is “very likely” caused by human activities such as burning fossil fuels. It said the earth has warmed by 0.76 degrees Celsius (1.37 degrees Fahrenheit) since the 19th century, and will rise by an additional 1.1 to 6.4 degrees this century.

Some questions remain unresolved, such as warming’s impact on the strength and frequency of hurricanes, said Somerville, a lead author of the 2007 study. At the same time, “we didn’t find holes” in that report, he said.

Treaty Prospects
More than 190 nations will meet in Copenhagen from Dec. 7 to Dec. 18 in an effort to agree on international limits on emissions that contribute to global warming. World leaders, including U.S. President Barack Obama, have said a treaty won’t be completed in Copenhagen, and UN Secretary General Ban Ki-Moon said he’s hoping for agreement next year.

Today’s report was caught up in the long-running dispute between scientists who study global warming and skeptics who question the extent of human contributions to the phenomenon.

Private e-mails among scientists, including several of those who contributed to today’s report, were disclosed last week. Skeptics said the exchanges showed efforts to stifle opposing viewpoints and to overstate the case for the human role in global warming. The e-mails were obtained from a computer at the University of East Anglia in the U.K.

‘Scary Predictions’ 

Marc Morano, a skeptic who is editor of a Web site on the issue, said today’s report “is nothing more than an if-maybe- could-possibly-happen in the future. It’s really a bunch of scary predictions timed for a UN political meeting.”

The researchers prepared the report in part to answer challenges to the scientific consensus, Somerville said.
“There’s been an active campaign of disinformation that tends to make the issue seem confusing and to make the science community seem conflicted,” he said.

Carbon dioxide, methane and nitrous oxide, the main man- made greenhouse gases blamed for global warming, increased to record concentrations in the atmosphere last year, the UN said today in a separate report. Carbon dioxide, produced from burning fossil fuels and deforestation, rose to 385.2 parts per million, or molecules per million molecules of dry air. That’s 2 ppm higher than a year earlier.

The G-8 group of nations has agreed to a proposal to keep the increase in global temperatures to within 2 degrees Celsius of pre-industrial times, a target that would avert the worst effects of climate change. Even if emissions rates stabilize at current levels, there’s a 25 percent chance that warming will exceed the 2 degree target, according to today’s report.

Exceeding Safe Levels
“We have already almost exceeded the safe level of emissions that would ensure a reasonably secure climate future,” Matthew England, joint director of the Climate Change Research Centre of the University of New South Wales, Australia, said in a statement. “Within just a decade global emissions need to be declining rapidly.”

Today’s report also found that summer melting of Arctic sea ice is happening faster than expected and that there has been “no significant changes” in the rate of global temperature rise.

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