Feb 27, 2006

Let's Talk "Sudden Climate Change"

It was a balmy, spring day in January when I bumped into my neighbor outside. "Lovely weather," he remarked.

"Lovely. But a little creepy when you consider it comes courtesy of global warming."

"Global warming? Maybe hundreds of years from now." He made a hasty break for his SUV.

Here in the United States, where the reality of global climate change is still being debated, such denial is common. However, as I tried to explain to my rapidly retreating neighbor, we are seeing the results of global warming right now, all over the world, and there is the very real threat that those results will escalate dramatically in a very few years. There are whisperings of something called "sudden climate change." New research is showing that we are ahead of many of the timetable predictions. Worse, at a certain point the changes in our climate become cumulative. As John Atcheson explains in "Hotter, Faster, Worser," there are developing "feedback loops" in which the increasing warmth of the planet is giving birth to sudden outpourings of carbon dioxide and methane, which accelorate the warming, which increases the release of carbon dioxide and methane... Well, you can see where this is going.

...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 a 100,000 years for the earth to recover.

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

While I've been concerned about the environment for many years, there was a tipping point in my own consciousness in 2003 when I read reports of vast numbers of French citizens dropping dead from a heat wave. Atcheson puts the final tally of European heat related deaths that summer at 35,000. But aside from the alarming freakishness of this event, there were more far-reaching consequences. As Atcheson explains:

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.

This is the type of occurence that could lead to sudden climate change. And Atcheson explains that there are similar concerns about other regions.

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.

All of this paints a picture far worse than people like my neighbor are taking in. The impact of global warming is not in the indefinite future. It's now. As a recent Washington Post article explains, increasing global temperatures are estimated to claim 150,000 lives and cause roughly 5 million illnesses a year. Most of the victims of the rising occurences of malaria, malnutrition, and diarrhea are the world's poor, whose lack of political clout has made their deaths largely invisible to suburban America.

But the "oceans will not protect us" from the impact of sudden climate change and it could occur within 20 years. A report ordered by the Pentagon, and quietly buried without fanfare, posited that the effects of climate shift could plunge us into a world war.

Climate change over the next 20 years could result in a global catastrophe costing millions of lives in wars and natural disasters..

A secret report, suppressed by US defence chiefs and obtained by The Observer, warns that major European cities will be sunk beneath rising seas as Britain is plunged into a 'Siberian' climate by 2020. Nuclear conflict, mega-droughts, famine and widespread rioting will erupt across the world.

The document predicts that abrupt climate change could bring the planet to the edge of anarchy as countries develop a nuclear threat to defend and secure dwindling food, water and energy supplies. The threat to global stability vastly eclipses that of terrorism, say the few experts privy to its contents.

'Disruption and conflict will be endemic features of life,' concludes the Pentagon analysis. 'Once again, warfare would define human life.'

The theorist behind this alarming prediction is the respected military advisor Andrew Marshall; known in National Defense circles as "Yoda." He was appointed by Donald Rumsfeld in pre-9/11 2001 to bring his considerable influence to bear on the reshaping of the American military. But the report Marshall delivered in early 2004 concluded that the threat of an environmental catastrophe is far greater than that of global terrorism.

Worse, we may have already passed the point of no return. Says Atcheson:

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.

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