The New York Times offers this brief, but useful summary of some of the evidence for human-caused glboal warming. Since it now seems incontrovertible that the planet is, indeed, warming up, the right-wing line has shifted to a rejection of humanity’s role in the trend. I suspect as more data comes in, this line will prove untenable as well:
In the panel’s last report, issued in 2001, and in more recent studies reviewed for the coming report, various trends provide clues that human activity, rather than natural phenomena, probably caused most of the recent warming. A number of trends have been identified:
- The global average minimum nighttime temperature has risen. (This is unlikely to be caused by some variability in the sun, for example, and appears linked to the greenhouse gases that hold in heat radiating from the earth’s surface, even after the sun has gone down.)
- The stratosphere, high above the earth’s surface, has cooled, which is an expected outcome of having more heat trapped by the gases closer to the surface, in the troposphere. (Scientists say that variations in the sun’s output, for example, would instead cause similar trends in the two atmospheric layers instead of opposite ones.)
- There has been a parallel warming trend over land and oceans. (In other words, the increase in the amount of heat-trapping asphalt cannot be the only culprit.)
When you’re done reading that, you can have a look at this companion piece about how warming has resulted in new islands appearing off the coast of Greenland:
All over Greenland and the Arctic, rising temperatures are not simply melting ice; they are changing the very geography of coastlines. Nunataks — “lonely mountains” in Inuit — that were encased in the margins of Greenland’s ice sheet are being freed of their age-old bonds, exposing a new chain of islands, and a new opportunity for Arctic explorers to write their names on the landscape.
“We are already in a new era of geography,” said the Arctic explorer Will Steger. “This phenomenon — of an island all of a sudden appearing out of nowhere and the ice melting around it — is a real common phenomenon now.”