Scientists find errors in global
By Dan Vergano, USA TODAY
Satellite and weather-balloon research released Friday removes a last
bastion of scientific doubt about global warming, researchers say.
Surface temperatures have shown small but
steady increases since the 1970s, but the tropics had shown little
atmospheric heating — and even some cooling. Now, after sleuthing
reported in three papers released by the journal Science,
revisions have been made to that atmospheric data.
Climate expert Ben Santer of Lawrence Livermore
National Laboratory in California, lead author of one of the papers,
says that those fairly steady measurements in the tropics have been a
key argument "among people asking, 'Why should I believe this global
warming hocus-pocus?' "
After examining the satellite data, collected
since 1979 by National Oceanic and Atmospheric Administration weather
satellites, Carl Mears and Frank Wentz of Remote Sensing Systems in
Santa Rosa, Calif., found that the satellites had drifted in orbit,
throwing off the timing of temperature measures. Essentially, the
satellites were increasingly reporting nighttime temperatures as
daytime ones, leading to a false cooling trend. The team also found a
math error in the calculations.
"Our hats are off to (them). They found a real
source of error," says atmospheric scientist John Christy of the
University of Alabama at Huntsville, whose team produced the lower
When examining the balloon data, Yale
University researchers found that heating from tropical sunlight was
skewing the temperatures reported by sensors, making nights look as
warm as days.
Once corrected, the satellite and balloon
temperatures align with other surface and upper-atmosphere measures,
as well as climate change models, Santer says.
Global warming's pace over the past 30 years
has actually been quite slow, a total increase of about 1 degree
Fahrenheit. It is predicted to accelerate in this century.
Mark Herlong of the George C. Marshall
Institute declined to comment. The group, financed by the petroleum
industry, has used the data disparities to dispute the views of
global-warming activists. In recent years, however, the institute has
softened its public statements, acknowledging that the planet is
indeed getting warmer but still maintaining that the change is
happening so slowly that the impact is minimal.