Global Warming Impact on Polar Ice Sheets Confirmed
Recent studies using satellite data of the Antartic and Greenland ice sheets confirm a extensive thinning and other effects of global warming:
Climate warming is changing how much water remains in Earth’s greatest treasuries of ice and snow, NASA scientists have confirmed. The most comprehensive survey ever undertaken of the enormous ice sheets covering both Greenland and Antarctica shows a net loss of ice to the sea.The 10 year survey shows there was a net loss of ice from the combined polar ice sheets between 1992 and 2002 and a corresponding rise in sea level.
The 20 billion net tons of water melted into the oceans each of those 10 years is equivalent to the amount of fresh water annually used in homes, businesses, and farming in New York, New Jersey, and Virginia.
The survey documented extensive thinning of the West Antarctic ice shelves, an increase in snowfall in the interior of Greenland, and thinning of ice at the edges.
Other recent studies have shown increasing losses of ice in parts of both these sheets. This NASA survey is the first to inventory the losses of ice and the addition of new snow on both in a consistent and comprehensive way throughout an entire decade.
“If the trends we’re seeing continue and climate warming continues as predicted, the polar ice sheets could change dramatically,” said survey lead author Dr. H. Jay Zwally of NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
“The Greenland ice sheet could be facing an irreversible decline by the end of the century,” Zwally warned.
Source: Environmental News Service
March 17th, 2006 at 6:00 pm
Climate warming indeed may be changing the amount of water locked in our polar treasuries . . . but lets not jump to the conclusion that this is the result of anthropogenic warming. Sea level has already risin over 300 feet in the last 18,000 years or so. Global warming (but not anthropogenic global warming) is a geologic fact – - as is global cooling. Many geologists believe that we are living in an interglacial period, and that the ice will advance again.
The IPCC’s reliance on Mann’s “hockey stick” graph to “prove” anthropogenic global warming has been proven improvident by Mcintyre and McKitrick. What is disconcerting to me is that scientific papers should be peer reviewed before being relied upon, and the fact that Mann’s paper gained so much acceptance with an apparent inadequate review tells me that politics was behind the issue.
I cannot say that anthropogenic global warming is not occurring. I can say that I remain skeptical—and will continue to remain skeptical until the mechanism behind the advance and retreat of the ice sheets that once covered CNY is explained.
March 18th, 2006 at 6:55 pm
Thanks for your comment.
The IPCC’s assessments provide comprehensive reviews of the literature on the subject, so I will have to take issue with the implication that they lack scientific merit or are wanting for peer review. Regarding Mcintyre and McKitrick critique of Mann’s “Hockey Stick” the blog, RealClimate debunks this better than I could (http://www.realclimate.org/index.php?p=11). I found this esp. charming:
“False claims of the existence of errors in the Mann et al (1998) reconstruction can also be traced to spurious allegations made by two individuals, McIntyre and McKitrick (McIntyre works in the mining industry, while McKitrick is an economist). The false claims were first made in an article (McIntyre and McKitrick, 2003) published in a non-scientific (social science) journal “Energy and Environment”...” (Who is in need of peer-review?)
Skeptical or not, the scientific consensus is that global warming is occurring and is likely due to human activities:
http://www.agu.org/sci_soc/policy/positions/climate_change.shtml
http://nationalacademies.org/onpi/06072005.pdf
http://www.ametsoc.org/policy/climatechangeresearch_2003.html
Consesus statements certainly do not constitute proof. But its becoming fairly clear that the global warming deniers are running out of rope to hang themselves with. When it becomes increasingly neccessary to debunk the so-called “debunkers” (e.g. Crichton), I would ask whose politics is cloudy whose judgement here?
March 18th, 2006 at 10:50 pm
Interesting links AZ. I looked at the realclimate.org piece ... Whenever a writer throws around the terms “false claims” and “spurious allegations,” argues based on “the consensus” and points to someone’s background (“he’s with the mining industry” or “he’s an economist”) to cast doubt on that person’s conclusions, I tend to discount what the writer has to say. If someone needs to be discredited, it would be better to just focus on specific flaws in their data, in their chain of logic leading from the data to the conclusion, or on their prior inconsistent statements. Were McIntyre and McKitrick in error when they concluded that no matter what data was entered into Mann’s model, the “hockey stick” popped out? Did anyone else try to replicate M&M’s results and fail?
I am not a climate scientist and do not read the papers—I don’t have the time. Nevertheless, I am scientifically trained and understand the theories. However, I will NOT accept theories as true just because the crowd accepts them (why should anyone be different than Galileo, who also refused to go with the flow). I’ll accept those things that square with what I already know (and I’ll also accept the fact that I might be wrong becaue of it). I understand the theory about CO2 and the greenhouse effect. But I also know that the ice advanced and retreated over CNY 4 times without human involvement. Assuming that humans ARE having an effect through their CO2 output and the greenhouse effect, is it significant against the natural background “noise”? Sea level has already risen over 300 ft. At this point, I cannot tell that what we are observing now is significantly different from what has occurred in the past . . . and as a result, am unwilling to accept the costs associated with Kyoto or RGGI (but I WOULD we willing to accept a switch away from fossil fuels for geopolitical reasons, because that threat I can perceive). Anyway, this will always be an interesting topic to discuss
April 30th, 2006 at 7:06 pm
[...] While the greenhouse theory may be sound, the conclusion that gasses from cars and factories are the major cause of warming (called manmade or “anthropogenic” warming) is far from proven, although a consensus is claimed. CO2, the product of burning fossil fuels, is the culprit most cited along with the fact that a sharp rise in atmospheric CO2 concentration has been documented since the mid-1800s, along with a rise in average world temperature since that time. See Summary for Policymakers, Intergovernmental Panel on Climate Change (IPCC). [...]