[Reader-list] Fwd: Carbon dioxide in Atmosphere

[Jeebesh]

What does this do to our ideas of good life?

Begin forwarded message:

> From: Ananth S <sananth99 at gmail.com>
> Date: 21 June 2009 7:46:12 PM GMT+05:30
> To: bemous2007 at gmail.com
> Subject: Carbon dioxide in Atmosphere
>
> 2.1 Million-Year High Measured for Carbon Dioxide in Atmosphere
> By Jeremy van Loon
> http://www.bloomberg.com/apps/news?pid=newsarchive&sid=aG5p2kBin538
> June 18 (Bloomberg) -- Carbon dioxide in the earth’s atmosphere has  
> risen to its highest level in at least 2.1 million years, according  
> to a new investigation of the greenhouse gas’s role in ice ages over  
> the millennia.
>
> Researchers including Columbia University’s Baerbel Hoenisch drilled  
> into the ocean floor off the coast of Africa to remove shells of  
> ancient marine animals called foraminifera that contain climate  
> records, according to the study published today on Science’s Web  
> site. Previous evidence of CO2 concentrations found in columns of  
> Arctic ice go back just 800,000 years.
>
> Carbon dioxide, which traps heat close to earth, is the main  
> contributor to global warming, threatening to raise sea levels and  
> disrupt food production and water supplies, United Nations  
> scientists have said. The marine sediment indicated “stable” levels  
> of atmospheric CO2 at less than 250 molecules per million molecules  
> of air, compared with about 385 today.
>
> “What’s remarkable is how little CO2 concentration changed in the  
> past,” said Jerry McManus, a paleoclimatology professor at Columbia  
> who participated in the study. “What we’re seeing now is the same  
> magnitude of natural variations happening in only a few decades.”
>
> The CO2 concentration ranged between 181 and 297 parts per million  
> over the period studied. It may be necessary to go back as far as  
> 2.7 million years to find levels of CO2 similar to today’s, the  
> study concluded, without attributing reasons for previous surges.
>
> Carbon Spike
>
> If the world continues to burn coal and oil and cut down forests  
> that store carbon, the amount of CO2 in the atmosphere may more than  
> double to 900 parts per million in the next century, the UN’s  
> Environment Programme Executive Director Achim Steiner has said.
>
> Negotiators at UN-sponsored talks are attempting to set limits on  
> CO2 emissions. Delegates are focused on restricting output of the  
> gas, which has grown 2 percent since industrialization in the 1800s,  
> to 450 parts per million and slowing the rise in average global  
> temperature to 2 degrees Celsius (3.6 Fahrenheit) over the next  
> century.
>
> “With unabated emissions, many trends in climate will likely  
> accelerate, leading to an increasing risk of abrupt or irreversible  
> climatic shifts,” 10 universities said today in a report suggesting  
> that climate change was underestimated.
>
> The United Nations Intergovernmental Panel on Climate Change in 2007  
> blamed global warming on emissions of such gases and warned of  
> increased flooding and drought as temperatures continue to rise.  
> Greenhouse gases also include water vapor, methane and nitrous oxide.
>
> ‘Unprecedented’
>
> The study published in Science today “is the best existing record so  
> far that shows atmospheric concentrations of carbon dioxide,” said  
> Columbia’s McManus. “It strengthens the case that this is fairly  
> unprecedented” for an increase in CO2.
>
> Other evidence of greenhouse gas concentration has been discovered  
> in ice. Polar researchers reported last year in the journal Nature  
> that carbon dioxide was at an 800,000-year high, after studying  
> bubbles trapped in ice drilled from the Antarctic.
>
> Hoenisch and colleagues investigated the role of the carbon cycle in  
> climate change and concluded that CO2 was probably not responsible  
> for lengthening the time between major ice ages to 100,000 years  
> from 40,000, countering a supposition that massive ice sheets grew  
> and receded because of gradually decreasing levels of carbon dioxide.
>
> Even with the likelihood of the earth warming up in the coming  
> centuries, we’re headed for another ice age at some point thousands  
> of years in the future, said McManus.
>
> “The earth is moving into an increasingly glaciated state,” he said.  
> “It’s just that the intervals between ice ages, which we’re living  
> in now, have become longer and warmer.”
>