Global warming not only is real, but "humans are almost entirely the cause," a self-described former climate change skeptic has declared.
"Call me a converted skeptic," Richard A.
Muller, University of California, Berkeley physics professor said in an opinion
piece posted online Saturday in The New York Times.
Muller in October released results from the Berkeley
Earth Surface Temperature (BEST) project, set up for global warming skeptics,
that showed that since the mid-1950s, global average temperatures over land
have risen by 0.9 degrees Celsius (1.6 degrees Fahrenheit).
In his new statement, Muller said, "Last year,
following an intensive research effort involving a dozen scientists, I
concluded that global warming was real and that the prior estimates of the rate
of warming were correct. I’m now going a step further: Humans are almost
entirely the cause."
He credited his turnaround to "careful and objective
analysis" by BEST, explaining:
“Our results show that the average temperature of the
earth’s land has risen by two and a half degrees Fahrenheit over the past 250
years, including an increase of one and a half degrees over the most recent 50
years. Moreover, it appears likely that essentially all of this increase
results from the human emission of greenhouse gases. These findings are
stronger than those of the Intergovernmental Panel on Climate Change, the
United Nations group that defines the scientific and diplomatic consensus on
global warming. ... ”
Money for the BEST study came from five foundations,
including one established by Microsoft founder Bill Gates and another from the
Charles Koch Charitable Foundation, set up by the billionaire coal magnate and
widely seen as a source of money for conservative organizations and initiatives
that have fought efforts to curb greenhouse-gas emissions.
Muller said in his opinion piece he remains skeptical of
some climate-change claims.
"Hurricane Katrina cannot be attributed to global
warming. The number of hurricanes hitting the United States has been going
down, not up; likewise for intense tornadoes. Polar bears aren’t dying from
receding ice, and the Himalayan glaciers aren’t going to melt by 2035."
