Rising sea levels to exceed expectations, climate change congress hears

Sea levels around the world could rise by as much as one metre by 2100, the International Scientific Congress on Climate Change has heard.

Meeting in Copenhagen, Denmark, from March 10 to 12, researchers told the conference that it looks “increasingly likely” that sea levels will rise by no less than 50 centimetres by 2100 and that a rise of more than one metre is a real possibility.

“This means that if emissions of greenhouse gases is not reduced quickly and substantially, even the best case scenario will hit low lying coastal areas housing one in ten humans on the planet hard,” a March 10 media release states.

In December 2008, a B.C. Ministry of Environment report concluded that decisions regarding land use and major long-term infrastructure projects in the province must consider local sea-level changes to effectively manage risks.

The ministry’s report stated that sea levels for the Fraser River delta could rise by as much as 120 centimetres by 2100. It cautions that while probable estimates for sea level rises in B.C. range from 11 centimetres for Nanaimo to 50 centimetres for the Fraser, the possible range could be much greater.

New research presented at the ISCCC conference included estimates for rising sea levels that are significantly greater than earlier predictions made by the Intergovernmental Panel on Climate Change.

The IPCC last delivered an assessment report on rising sea levels in 2007. That report predicted sea levels to rise by 18 to 59 centimetres by 2100.

According to the release, the significant disparity between the two sets of data can in part be attributed to the 2007 report’s failure to take into account contributing factors to sea-level increases such as how ice sheets react to the effects of a warmer climate.

The latest research includes insight based on the loss of ice from the Antarctic and Greenland ice sheets, according to the release.

“The numbers from the last IPCC are a lower bound because it was recognized at the time that there was a lot of uncertainty about ice sheets,” Eric Rignot, a professor at the University of California at Irvine and senior research scientist at NASA’s Jet Propulsion Laboratory, states in the release.

Konrad Steffen, of the University of Colorado at Boulder and cochair of the congress session on sea level rise, then states in the release, “The ice loss in Greenland has accelerated over the last decade. The upper range of sea level rise by 2100 might be above one metre or more on a global average, with large regional differences depending where the source of ice loss occurs.”

John Church, of the Centre for Australian Weather and Climate Research and the lead speaker in the sea level session, attributed rising sea levels to continually warming oceans and the increasingly rapid rate at which mountain glaciers are melting.

According to the release, more than 2,000 participants are registered to attend the ISCCC conference and nearly 1,600 scientific contributions from 70 countries were received by the ISCCC.

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