Past the point of no return is cool when you're about to blow a load, but not so cool when the fate of the planet and at least a goodly portion of humanity (and our life as we know it) is at stake.
Excellent science-oriented blog about climate change, chock full of charts, graphs and maps (not full of BS from Exxon-funded "dissenters"):
http://www.wunderground.com/climate/
(see especially their Worldwide Temperature Anomalies maps - done every month!)
Sobering article, very much worth the read:
http://www.latimes.com/news/science/environment/la-na-global-warming22-2009feb22,0,646220.story
Excerpt:
Nowhere is the evidence of a heating planet more dramatic than in the polar regions. Over the last 50 years, the Arctic has warmed twice as fast as the rest of the globe. Last summer, for the first time in recorded history, the North Pole could be circumnavigated. Ice sheets on Greenland and West Antarctica are melting rapidly. Polar bears and emperor penguins are threatened with extinction.
Even as glaciers and sea ice have captured the most headlines, growing concern is now focused on the transformation of permafrost -- soils that are frozen year-round.
Today, 20% of Earth's land surface is locked up in a deep freeze. But scientists predict that air temperature in the Arctic is likely to rise as much as 6 degrees Celsius (10.8 degrees Fahrenheit) by the end of the century. That is expected to boost the emission of carbon compounds from soils.
The upper 3 meters (about 10 feet) of permafrost store 1.7 trillion metric tons of carbon, more than double the amount in the atmosphere today, according to a recent study in the journal Bioscience.
"We are seeing thawing down to 5 meters," says geophysicist Vladimir Romanovsky of the University of Alaska. "A third to a half of permafrost is already within a degree to a degree and a half [Celsius] of thawing."
If only 1% of permafrost carbon were to be released each year, that could double the globe's current annual carbon emissions, Romanovsky notes. "We are at a tipping point for positive feedback," he warns, referring to a process where warming spurs emissions, which in turn generate more heat, in an uncontrollable cycle.
Excellent science-oriented blog about climate change, chock full of charts, graphs and maps (not full of BS from Exxon-funded "dissenters"):
http://www.wunderground.com/climate/
(see especially their Worldwide Temperature Anomalies maps - done every month!)
Sobering article, very much worth the read:
http://www.latimes.com/news/science/environment/la-na-global-warming22-2009feb22,0,646220.story
Excerpt:
Nowhere is the evidence of a heating planet more dramatic than in the polar regions. Over the last 50 years, the Arctic has warmed twice as fast as the rest of the globe. Last summer, for the first time in recorded history, the North Pole could be circumnavigated. Ice sheets on Greenland and West Antarctica are melting rapidly. Polar bears and emperor penguins are threatened with extinction.
Even as glaciers and sea ice have captured the most headlines, growing concern is now focused on the transformation of permafrost -- soils that are frozen year-round.
Today, 20% of Earth's land surface is locked up in a deep freeze. But scientists predict that air temperature in the Arctic is likely to rise as much as 6 degrees Celsius (10.8 degrees Fahrenheit) by the end of the century. That is expected to boost the emission of carbon compounds from soils.
The upper 3 meters (about 10 feet) of permafrost store 1.7 trillion metric tons of carbon, more than double the amount in the atmosphere today, according to a recent study in the journal Bioscience.
"We are seeing thawing down to 5 meters," says geophysicist Vladimir Romanovsky of the University of Alaska. "A third to a half of permafrost is already within a degree to a degree and a half [Celsius] of thawing."
If only 1% of permafrost carbon were to be released each year, that could double the globe's current annual carbon emissions, Romanovsky notes. "We are at a tipping point for positive feedback," he warns, referring to a process where warming spurs emissions, which in turn generate more heat, in an uncontrollable cycle.
