Re: [A-List] Global Warming: The vicious circle

[Michael Hudson <michael.hudson@xxxxxxxxxxxxx>]

Dear Bill,
    You and I probably won't be around by 2100 (unless our brains are in
laboratory testtubes, movie-style), but at Harvard a few months ago I DID
learn of models that forecast the North Atlantic Gulf Stream being pushed
under within one or two decades. Hence, as I wrote you off-list, my friend
Carl Lamberg-Karlovsky pointed out that "global warming is an EVENT, not a
PROCESS." It occurs in a step function.
    Michael Hudson


On 1/29/07 4:11 AM, "Bill Totten" <shimogamo@xxxxxxxxxxxxx> wrote:

> by Steve Connor, Science Editor
> 
> The Independent & The Independent on Sunday
> 
> Independent.co.uk Online Edition (January 29 2007)
> 
> 
> The effects of man-made emissions of carbon dioxide are being felt on every
> inhabited continent in the world with very different parts of the climate now
> visibly responding to human activity.
> 
> These are among the main findings of the most intensive study of climate
> change
> by 2,000 of the world's leading climate scientists. They conclude that there
> is
> now little doubt that human activity is changing the face of the planet.
> 
> In addition to rising surface temperatures around the world, scientists have
> now
> linked man-made emissions of greenhouse gases to significant increases in
> ocean
> temperatures, rises in sea levels and the dramatic melting of Arctic sea ice
> over the past 35 years.
> 
> A draft copy of the fourth report of the Intergovernmental Panel on Climate
> Change (IPCC) says that global temperature rises this century of between two
> and
> 4.5 degrees Celsius are almost inevitable. Ominously, however, it also says
> that
> much higher increases of six degrees Celsius "or more" cannot be ruled out.
> 
> The final version of the IPCC's latest report is to be published on Friday but
> a
> draft copy, seen by The Independent, makes it clear that climate change could
> be
> far worse than previously thought because of potentially disastrous "positive"
> feedbacks which could accelerate rising temperatures.
> 
> A warmer world is increasing evaporation from the oceans causing atmospheric
> concentrations of water vapour, a powerful greenhouse agent, to have increased
> by four per cent over the sea since 1970. Water vapour in the atmosphere
> exacerbates the greenhouse effect. This is the largest positive feedback
> identified in the report, which details for the first time the IPCC's concern
> over the uncertainties - and dangers - of feedback cycles that may quickly
> accelerate climate change.
> 
> All the climate models used by the IPCC also found that rising global
> temperatures will erode the planet's natural ability to absorb man-made carbon
> dioxide. This could lead to carbon dioxide concentrations in the atmosphere
> rising by a further 44 per cent, causing global average temperatures to
> increase
> by an additional 1.2 Celsius by 2100.
> 
> The IPCC's Fourth Assessment Report will go further than any of its three
> previous reports in linking the clear signs of global climate change with
> increases in man-made emissions of carbon dioxide and other greenhouse gases
> since the start of the Industrial Revolution.
> 
> "Confidence in the assessment of the human contributions to recent climate
> change has increased considerably since the Third Assessment Report", says the
> draft report. This is due to the stronger signs of climate change emerging
> from
> longer and more detailed records and scientific observations, it says.
> 
> The "anthropogenic signal" - the visible signs of human influence on the
> climate
> - has now emerged not just in global average surface temperatures, but in
> global
> ocean temperatures and ocean heat content, temperature extremes on the land
> and
> the rapidly diminishing Arctic sea ice. "Anthropogenic warming of the climate
> system is widespread and can be detected in temperature observations taken at
> the surface, in the free atmosphere and in the oceans", the draft report says.
> "It is highly likely [greater than 95 per cent probability] that the warming
> observed during the past half century cannot be explained without external
> forcing [human activity]."
> 
> The report adds that global warming over the past fifty years would have been
> worse had it not been for the counterbalancing influence of man-made emissions
> of aerosol pollutants, tiny airborne particles that reflect sunlight to cause
> atmospheric cooling. "Without the cooling effect of atmospheric aerosols,
> it is likely that greenhouse gases alone would have caused more global mean
> temperature rise than that observed during the last fifty years", the draft
> report says.
> 
> "The hypothetical removal from the atmosphere of the entire current burden of
> anthropogenic sulphate aerosol particles would produce a rapid increase of
> about
> 0.8 degrees Celsius within a decade or two in the globally averaged
> temperature."
> 
> The IPCC says that over the coming century we are likely to see big changes to
> the Earth's climate system. These include:
> 
> * Heat waves, such as the one that affected southern Europe in summer 2003,
> are expected to be more intense, longer-lasting and more frequent.
> 
> * Tropical storms and hurricanes are likely to be stronger,
> with increased rainfall and higher storm surges flooding coastlines.
> 
> * The Arctic is likely to become ice free in the summer, and there will be
> continued melting of mountain glaciers, ice caps and ice sheets.
> 
> * Sea levels will rise significantly even if levels of carbon dioxide are
> stabilised. By 2100 sea levels could be 0.43 metres higher on average than
> present, and by 2300 they could be up to 0.8 metres higher.
> 
> The IPCC also finally nails the canard of the climate sceptics who argue that
> global warming is a myth or the result of natural climate variability; natural
> factors alone cannot account for the observed warming, the IPCC says. "These
> changes took place at a time when non-anthropogenic forcing factors (that is,
> the sum of solar and volcanic forcing) would be expected to have produced
> cooling, not warming.
> 
> "There is increased confidence that natural internal variability cannot
> account
> for the observed changes, due in part to improved studies demonstrating that
> the
> warming occurred in both oceans and atmosphere, together with observed ice
> mass
> losses".
> 
> The report, the first draft of which was formulated last year,
> will be made public on Friday in Paris.
> 
> 
> Key findings of the IPCC's fourth assessment report
> 
> * Global temperatures continue to rise with eleven of the twelve warmest years
> since 1850 occurring since 1995. Computer models suggest a further rise of
> about
> three degrees Celsius by 2100, with a six degrees Celsius rise a distant
> possibility
> 
> * It is virtually certain (there is more than a 99 per cent probability) that
> carbon dioxide levels and global warming is far above the range of natural
> variability over the past 650,000 years
> 
> * It is virtually certain that human activity has played the dominant role
> in causing the increase of greenhouse gases over the past 250 years
> 
> * Man-made emissions of atmospheric aerosol pollutants have tended to
> counteract
> global warming, which otherwise would have been significantly worse
> 
> * The net effect of human activities over the past 250 years has very likely
> exerted a warming influence on the climate
> 
> * It is likely that human activity is also responsible for other observed
> changes to the Earth's climate system, such as ocean warming and the melting
> of the Arctic sea ice
> 
> * Sea levels will continue to rise in the 21st Century because of the thermal
> expansion of the oceans and loss of land ice
> 
> * The projected warming of the climate due to increases in carbon dioxide
> during
> the 21st Century is likely to cause the total melting of the Greenland ice
> sheet
> during the next 1,000 years, according to some computer forecasting models
> 
> * The warm Gulf Stream of the North Atlantic is likely to slow down during the
> 21st Century because of global warming and the melting of the freshwater
> locked
> up in the Greenland ice sheet. But no models predict the collapse of that warm
> current by 2100.
> 
> Also in this section
> 
>     * Where have all the birds gone?
>     * Shark! The great white fight and the creature from the deep
>     * Ice island the size of London threatens rigs
>     * Chic & cheerful (but not so great for the environment)
>     * Girl, 12, is fined for failing to recycle cardboard box
> 
> (c) 2006 Independent News and Media Limited
> 
> http://news.independent.co.uk/environment/article2193672.ece
> 
> http://www.billtotten.blogspot.com
> http://www.ashisuto.co.jp
>                  
> 
>