In an age of alarmism, skepticism, and shoddy science, it’s hard to know whom to trust when it comes to climate change. Both sides seem to have political presuppositions that bias their conclusions. The time is ripe for a new, independent perspective.
So when a group calling itself Berkeley Earth Surface Temperature (BEST) announced it would, in essence, start over and create new models from scratch, making its methods transparent to the public, scientists and opinion leaders across the spectrum welcomed it as a fresh, needed source of information. Berkeley physicist Richard Muller, the project’s leader, assembled a team of scientists who had largely remained neutral in their public opinions on global warming. He told the Guardian in February, “Science has its weaknesses and it doesn’t have a stranglehold on the truth, but it has a way of approaching technical issues that is a closer approximation of truth than any other method we have.”
The pursuit of truth though the rigorous application of the scientific method sounds right in line with the best aims of scholarship.
When I interviewed Muller this spring, he said, “science isn’t partisan.” He also said he couldn’t predict Berkeley Earth’s conclusions:
NAS: Do you expect Berkeley Earth’s findings to confirm, confirm with qualifications, or contradict the current consensus?
Muller: If I knew, I would be biased. I honestly don’t know.
On Friday the group released the initial results of its data analysis. They include four papers submitted for peer review, a video showing “global land-surface temperature from 1800 to the present,” and other raw data. Berkeley Earth says the purpose of releasing the results early is “to invite additional scrutiny.”
So what did the Berkeley scientists find? A two-page summary puts it succinctly: “Global warming is real.” Specifically, the group found “reliable evidence of a rise in the average world land temperature of approximately 1º Celsius since the mid-1950s.” The summary says the scientists’ “biggest surprise” was getting results that so closely matched those of earlier studies that have been accused of not being replicable. One difference between this and earlier studies is that BEST says it used five times as many temperature stations as prior groups.
BEST observed that while one-third of the stations showed a decline in temperature over the last 70 years, two-thirds showed an increase. The Economist hails the findings as persuasive:
Yet the Berkeley Earth study promises to be valuable. It is due to be published online with a vast trove of supporting data, merged from 15 separate sources, with duplications and other errors clearly signaled. At a time of exaggerated doubts about the instrumental temperature record, this should help promulgate its main conclusion: that the existing mean estimates are in the right ballpark. That means the world is warming fast.
Anthony Watts—the meteorologist who blogs at Watt’s Up With That? and has done some of his own independent research on climate change—remains unconvinced. He says he considers “the paper fatally flawed as it now stands” because its time periods do not match those of earlier studies to which BEST is comparing itself. Specifically Watts says BEST should use data from a 30 year period, not a 60 year period. He writes, “I welcome the BEST effort provided that appropriate time periods are used that match our work. But, by using time period mismatched comparisons, it becomes clear that the Muller et al paper in its current form lost the opportunity for a meaningful comparison” (emphasis in the original).
He also finds fault with BEST announcing its findings before any of them pass peer review: “Also I know that I’ll be criticized for my position on this, since I said back in March that I would accept their findings whatever they were, but that was when I expected them to do science per the scientific process.”
Watts further objects, “The issue of ‘the world is warming’ is not one that climate skeptics question; it is the magnitude and causes.” Basically he is saying that BEST hasn’t resolved anything. But BEST acknowledges that identifying the magnitude and causes was not part of this effort: “What Berkeley Earth has not done is make an independent assessment of how much of the observed warming is due to human actions.”
To the extent that the debate has been over whether or not warming is actually occurring, Berkeley Earth’s results do appear to add weight to the evidence for a slight temperature increase over the years. To the extent that the debate is really about humanity’s response to warming, we still face an overwhelming mass of unanswered questions.