Global warming

Dell Sherk
Fri, 03 Mar 2006 13:59:51 PST
Here is an interesting article that was quoted from John Atcheson on the
yahoo mesembs group:


> Over the past several months, the normally restrained voice of science 

> has taken on a distinct note of panic when it comes to global warming.

> How did we go from debating the "uncertainty" behind climate science 

> to near hysterical warnings from normally sober scientists about 

> irrevocable and catastrophic consequences? Two reasons.

> First, there hasn't been any real uncertainty in the scientific 

> community for more than a decade. An unholy alliance of key fossil 

> fuel corporations and conservative politicians have waged a 

> sophisticated and well-funded misinformation campaign to create doubt 

> and controversy in the face of nearly universal scientific consensus.

> In this, they were aided and abetted by a press which loved 

> controversy more than truth, and by the Bush administration, which has 

> systematically tried to distort the science and silence and intimidate 

> government scientists who sought to speak out on global warming. But 

> the second reason is that the scientific community failed to 

> adequately anticipate and model several positive feedback loops that 

> profoundly amplify the rate and extent of human-induced climate 

> change. And in the case of global warming, positive feedback loops can 

> have some very negative consequences. The plain fact is, we are fast 

> approaching - and perhaps well past - several tipping points which 

> would make global warming irreversible.

> In an editorial in the Baltimore Sun on December 15th, 2004 this 

> author outlined one such tipping point: a self-reinforcing feedback 

> loop in which higher temperatures caused methane - a powerful heat- 

> trapping greenhouse gas (GHG) - to escape from ice-like structures 

> called clathrates, which raised the temperature which caused more 

> methane to be released and so on. Even though there was strong 

> evidence that this mechanism had contributed to at least two extreme 

> warming events in the geologic past, the scientific community hadn't 

> yet focused on methane ices in 2004. Even among the few pessimists who 

> had, we believed - or hoped - that we had a decade or so before 

> anything like it began happening again.

> We were wrong.

> In August of 2005 a team of scientists from Oxford and Tomsk 

> University in Russia announced that a massive Siberian peat bog the 

> size of Germany and France combined was melting, releasing billions of 

> tons of methane as it did.

> The last time it got warm enough to set off this feedback loop was

> 55 million years ago in a period known as the Paleocene-Eocene Thermal 

> Maximum or PETM, when increased volcanic activity released enough GHGs 

> to trigger a series of self-reinforcing methane burps.

> The resulting warming caused massive die-offs and it took more than 

> 100,000 years for the earth to recover.

> It's looks like we're on the verge of triggering a far worse event. 

> At a recent meeting of the American Academy for the Advancement of 

> Sciences in St. Louis, James Zachos, foremost expert on the PETM 

> reported that greenhouse gasses are accumulating in the atmosphere at 

> thirty times the speed with which they did during the PETM.

> We may have just witnessed the first salvo in what could prove to be 

> an irreversible trip to hell on earth.

> There are other positive feedback loops we've failed to anticipate. 

> For example, the heat wave in Europe that killed 35,000 people in

> 2003 also damaged European woodlands, causing them to release more 

> carbon dioxide, the main GHG, than they sequester - exactly the 

> opposite of the assumptions built into our models, which treat forests 

> as sponges that sop up excess carbon.

> The same thing is happening to a number of other ecosystems that our 

> models and scientists have treated as carbon sinks. The Amazon 

> rainforest, the boreal forests (one of the largest terrestrial carbon 

> sinks in the planet), and soils in temperate areas are all releasing 

> more carbon than they are absorbing, due to global warming-induced 

> droughts, diseases, pest activity, and metabolic changes. In short, 

> many of the things we treat as carbon sponges in our models aren't 

> sopping up excess carbon; they're being wrung out and releasing extra 

> carbon.

> The polar ice cap is also melting far faster than models predict, 

> setting off another feedback loop. Less ice means more open water, 

> which absorbs more heat which means less ice, and so on.

> Even worse, we've substantially underestimated the rate at which 

> continental glaciers are melting.

> Climate change models predicted that it would take more than 1,000 

> years for Greenland's ice sheet to melt. But at the AAAS meeting in 

> St. Louis, NASA's Eric Rignot outlined the results of a study that 

> shows Greenland's ice cover is breaking apart and flowing into the sea 

> at rates far in excess of anything scientists predicted, and it's 

> accelerating each year. If (or when) Greenland's ice cover melts, it 

> will raise sea levels by 21 feet - enough to inundate nearly every sea 

> port in America.

> In the Antarctic seas, another potentially devastating feedback loop 

> is taking place. Populations of krill have plummeted by 80% in the 

> last few years due to loss of sea ice. Krill are the single most 

> important species in the marine foodchain, and they also extract 

> massive amounts of carbon out of the atmosphere. No one predicted 

> their demise, but the ramifications for both global warming and the 

> health of marine ecosystems are disastrous. This, too, will likely 

> feed on itself, as less krill means more carbon stays in the 

> atmosphere, which means warmer seas, which means less ice, which means 

> less krill and so on in a massive negative spiral.


> One of our preeminent planetary scientists, James Lovelock, believes 

> that in the not too distant future humans will be restricted to a 

> relatively few breeding pairs in Antarctica. It would be comfortable 

> to dismiss Professor Lovelock as a doom and gloom crazy, but that 

> would be a mistake. A little over a year ago at the conclusion of a 

> global conference in Exeter England on Avoiding Dangerous Climate 

> Change, scientists warned that if we allowed atmospheric 

> concentrations of GHG to exceed 400 ppm, we could trigger serious and 

> irreversible consequences. We passed that milestone in 2005 with 

> little notice and no fanfare.

> The scientific uncertainty in global warming isn't about whether it's 

> occurring or whether it's caused by human activity, or even if it will 

> "cost" us too much to deal with it now. That's all been settled.

> Scientists are now debating whether it's too late to prevent planetary 

> devastation, or whether we have yet a small window to forestall the 

> worst effects of global warming.


> Our children may forgive us the debts we're passing on to them, they 

> may forgive us if terrorism persists, they may forgive us for waging 

> war instead of pursuing peace, they may even forgive us for 

> squandering the opportunity to put the nuclear genie back in the 

> bottle. But they will spit on our bones and curse our names if we pass 

> on a world that is barely habitable when it was in our power to 

> prevent it.


> And they will be right to do so.


> John Atcheson's writing has appeared in the Washington Post, the 

> Baltimore Sun, the San Jose Mercury News, the Memphis Commercial 

> Appeal, as well as in several wonk journals. Email to:

> atchman@





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