Friday, December 14, 2007

HANG ON! We've Crossed the Tipping Point!

Earth has already crossed a number of climate change "tipping points" at which today's levels of greenhouse gases will cause additional large and rapid changes, a leading climate scientist said yesterday.

But it's not too late to avoid much of the damage by curbing the use of fossil fuels such as oil and coal, climatologist James Hansen added during a presentation at the American Geophysical Union fall meeting in San Francisco.

Such fuels are responsible for most of human-caused emissions of carbon dioxide (CO2), which are widely believed to be driving global warming.

Today's level of CO2 in the atmophere is enough to cause Arctic sea ice cover and massive ice sheets such as in Greenland to eventually melt away, said Hansen, of the NASA Goddard Institute for Space Studies in New York City.

Climate zones such as the tropics and temperate regions will continue to shift, and the oceans will become more acidic, endangering much marine life, he added. (Related: "Climate Change Pushing Tropics Farther, Faster" [December 3, 2007].)

"I think in most of these cases, we have already reached the tipping point," Hansen said.


Feel that sensation? The one just before the wild drop on the rollercoaster? Yep. We might just be RIGHT there.

1 comment:

Zach said...

I'm not surprised. As you know, I live in Anchorage, Alaska. It did not snow this year until a few days ago. For December, it was downright BALMY (30's every day, 42 one time). That was very strange indeed, and I can tell you it's a direct result of climate change.

What's disappointing is that I don't think enough people care. They're rather drive SUV's than Priuses, even though it costs upwards of $100 to fill up some of those monsters.

I heard a talk today on NPR about how coral reefs are basically going extinct around the globe, most notably the Great Barrier Reef, which is quickly going white. It made me very sad, and the coral expert being interviewed was hopeful, but not optamistic about the future.