Sea Level Rise this Century Higher than Previously Thought
by Jeremy Elton Jacquot, Los Angeles on 07.21.07
We will most likely see larger than previously expected increases in sea levels over the next century according to a recent study conducted by a team of researchers from the Institute of Arctic and Alpine Research at the University of Colorado, Boulder. They anticipate that the global warming-induced melting of mountain glaciers and ice caps will account for the brunt of that rise, as much as 2-3 times more than the amount originally predicted.
The scientists used satellite monitoring to determine the contribution of all land-based ice (except for Greenland and Antarctica's huge ice sheets) to rising sea levels and found that the volume of ice melting into the sea each year from ice caps and glaciers was 100 cubic miles (or 417 cubic km). They determined, however, that this volume had now increased by a further 3 cubic miles each year, prompted by an acceleration in the rate at which the ice caps and glaciers are melting.
Unlike what many other scientists have said — including, most prominently, NASA's James Hansen (who believes that a rise in 17 inches by 2100 will be mainly precipitated by the melting of ice sheets) — the authors of this study believe that the loss of ice from glaciers and ice caps will account for the majority of the expected rise in sea levels. "One reason for doing this study is the widely held view that the Greenland and Antarctic ice sheets will be the principal cause of sea-level rise. But we show that it is the glaciers and ice caps, not the two large ice sheets, that will be the big players in the sea rise for at least the next few generations," said Mark Meier, the study's lead scientist.
These latest results also run counter to the IPCC's own recent estimates, which predicted a rise in sea levels of about 3 inches (7.6 cm) this century (much too low, it now appears). This study, which does not take into account the likely contributions of the thermal expansion of water and the melting of ice sheets, suggests that sea levels will increase by an average of 4 - 9.5 inches and, when those last two events are factored in, by as much as 12 in.
Via ::The Independent: Sea levels may rise by 9 inches this century, scientists warn (newspaper), ::Science Reports: Glaciers Dominate Eustatic Sea-Level Rise in the 21st Century (magazine, sub. required), ::Climate Progress: The Independent blows the sea level rise story (blog)
See also: ::Flood Maps: View Sea Level Rise, ::Indian Ocean Shows Signs of Global Warming, ::Bad News: Climate Change Faster Than Expected
Thirsty for more? Check out these related articles:
I don't think there will be any "thermal expansion" from melting ice. Water expands when it freezes, not when it melts.
http://www.how-come.net/waterexpand.html
With warmer temps, more liquid water surface area and a lower oceanic salinity, won't a lot of the melting caps end up in the atmoshpere as clouds and rain? Anyone know? Any studies on how much water is in the atmospere as we measure our changing climate?
While this is very interesting and certainly something we need to watch for, the hard facts are that as of right now sea levels haven't shown any unusual rise or rate of rise.
To quote one study that was published on BBC News (source is at http://news.bbc.co.uk/2/hi/science/nature/5076322.stm),
the sea level in the Arctic Ocean is actually falling while other oceans are rising--which really doesn't make a lot of sense.
Just looking at the data it seems to me that we're seeing the standard "coming out of an Ice Age" levels of sea level rise...any problems that causes are pretty much our own fault for building next to water. We need a lot more study to understand just how weirdly interconnected all this stuff is.
Ferretman
Water expands below 4C - and also expands when heated. Thermal expansion of the oceans is a significant cause of worldwide sea level rise.
The Earth is awesome!