Dear Tom,
With all the snow and cold we are getting, how can the advocates of global warming
justify their arguments?
Paul Nadick, Round Lake, Ill.
Dear Paul,
Actually, no justification is necessary because the trend of global temperatures speaks
for itself. Since the end of the last glacial maximum about 15,000 years ago, global
temperatures have risen approximately 11 degrees. The rate of warming accelerated
greatly with the onset of the Industrial Revolution, and the Earth's average surface
temperature has risen, conservatively, about 1.5 degrees since the mid 1800s.
The grand sweep of global temperatures is upward, but many factors -- some
understood, some not -- can temporarily reverse the rising trend. For example, global
temperatures declined from the 1940s through the 1970s. It is a probably a mistake to
interpret a harsh winter as a permanent reversal of the trend of rising global
temperatures.
