Last week, The Wall Street Journal published an opinion piece by a few scientists and engineers who believe man-made climate change will have less impact on the environment than the vast majority of the scientific community has concluded it will.
Debate is normal and necessary in science — it occurred even on such questions as whether smoking causes lung cancer — so this disagreement is part of the process. However, people considering this issue should not lose sight of the fact that thousands of scientists studying decades of data have established an extremely strong link between carbon dioxide emissions and rising global temperatures. The underlying physics is well understood.
Further, hundreds, if not thousands, of peer-reviewed studies indicate that the impact on Earth’s climate will be substantial and dangerous. That is why so many scientific organizations and national academies have concluded climate change is a serious danger.
Many of the specific claims in the Journal piece also have already been definitively laid to rest. As the Union of Concerned Scientists has pointed out:
the authors claim there has been a "lack of warming" for 10 years…. [yet] 2011 was the 35th year in a row in which global temperatures were above the historical average and 2010 and 2005 were the warmest years on record.
Moreover, every decade since the 1950s has been warmer than the last.
The authors recycle an out-of-context quotation from Kevin Trenberth, distinguished senior scientist at the National Center for Atmospheric Research, to imply that he harbors doubts about warming. As Trenberth has said publicly:
I was not questioning the link between anthropogenic greenhouse gas emissions and warming, or even suggesting that recent temperatures are unusual in the context of short-term natural variability.
The authors misuse his words in service of what they call an “inconvenient fact” that is no fact at all. They ignore the multiple streams of scholarship that rebut their claims and point to rising global temperatures caused in large part by anthropogenic emissions.
In truth, climate skeptics may be finding it harder to cling to their doubts. Last year, for example, scientists at the University of California, Berkeley – in a study partially funded by climate skeptics – found that technical issues that skeptics claim skew global warming figures had no meaningful effect on them.
The Berkeley Earth project compiled more than a billion temperature records dating back to the 1800s from 15 sources around the world and found that the average global land temperature has risen by around 1C since the mid-1950s.
This figure agrees with the estimate arrived at by major groups that maintain official records on the world's climate, including Nasa's Goddard Institute for Space Studies in New York, the US National Oceanic and Atmospheric Administration (Noaa), and the Met Office's Hadley Centre, with the University of East Anglia, in the UK.
“My hope is that this will win over those people who are properly skeptical,” Richard Muller, a physicist and head of the project, said.