This whole article is a fantastic read:
Big melt meets big empty: Rethinking the implications of climate change and peak oil
by Richard Heinberg
snip
This year, Arctic ice reached a minimum extent of 4.13 million square kilometers, compared to the previous record low of 5.32 million square kilometers in 2005. This represented a decline of 22 per cent in just two years; the difference amounted to an expanse of ice roughly the size of Texas and California combined. Between 1979 and 2005, the rate of Arctic ice retreat had averaged 7 percent per decade; in the two years from September 2005 to September 2007 that rate increased to more than 20 percent. Moreover, the average thickness of the ice has declined by about half since 2001. Altogether, taking into account both geographic extent and thickness, summer Arctic sea ice has lost more than 80 per cent of its volume in four decades. While sea levels will not be directly affected by the total melting of the northern icecap since it floats on and thus displaces ocean water, that event will severely destabilize Greenland's ice pack - whose disappearance would cause sea levels to rise by several meters, inundating coastal cities home to hundreds of millions.
The organization Carbon Equity issued a report last month, "The Big Melt: Lessons from the Arctic Summer of 2007" (www.carbonequity.info/PDFs/Arctic.pdf), which draws conclusions from this disturbing new information:
The data surveyed suggests strongly that in many key areas the IPCC process has been so deficient as to be an unreliable and indeed a misleading basis for policy-making. . . . Take just one example: the most fundamental and widely supported tenet - that 2°C represents a reasonable maximum target if we are to avoid dangerous climate change - can no longer be defended. Today at less than a 1°C rise the Arctic sea ice is headed for very rapid disintegration, in all likelihood triggering the irreversible loss of the Greenland ice sheet and catastrophic sea level increases. Many species are on the precipice, climatechange- induced drought or changing monsoon patterns are sweeping every continent, the carbon sinks are losing capacity and the seas are acidifying. . . . The Arctic began to lose volume at least 20 years ago when the global temperature was about 0.5°C over the pre-industrial level. So we can now see that to protect the Arctic the average global temperature rise should be under 0.5°C.
According to the report, if this suggested 0.5°C precautionary warming cap were adopted, the target for allowable concentrations of atmospheric greenhouse gases would have to be about 320 ppm CO2 equivalents, a level that was passed more than 50 years ago.
more...
http://www.energybulletin.net/36739.html
Printer-friendly format
Email this thread to a friend
Bookmark this thread
(1000+ posts)
Send PM |
Profile |
Ignore
