With Speed and Violence Fred Pearce - Global Commons Institute

These findings alone should be enough to establish for even the most
diehard skeptic that man-made greenhouse gas emissions are making the
atmosphere warmer. Climate models developed by the U.S. government's
space agency, NASA, estimate that Earth is now absorbing nearly one watt
more than it releases per 10.8 square feet of its surface. This is a significant
amount. You could run a 60-watt light bulb off the excess energy supplied to
the area of the planet that a modest house occupies.
More contentious is whether we can actually feel the heat. Direct
planet-wide temperature records go back 150 years. They suggest that
nineteen of the twenty warmest years have occurred since 1980, and that the
five warmest years have all been since 1998. Could the thermometers be
misleading us? That has to be a possibility. The records, after all, are not a
formal planetary monitoring system; they are just a collection of all the data
that happen to be available.
Two important criticisms are made. One is that satellite sensors and
instruments carried into the atmosphere aboard weather balloons do not
back up the surface thermometers. The instrument data suggest that if air
close to the surface is warming, that warming is not spreading through the
bottom 6 miles of the atmosphere, known as the troposphere, in the way that
climate scientists predict. If true, this is very worrying, says Steve Sherwood,
a meteorologist at Yale University and author of a study of the problem: "It
would spell trouble for our whole understanding of the atmosphere."
Not surprisingly, skeptics have given great play to the suggestion that
satellites "prove" the surface thermometers to be at fault. Not so fast, says
Sherwood. The satellite data are untrustworthy, because they measure the
temperature in the air column beneath a satellite and cannot easily