Climate change skeptics and deniers often point to alleged flaws in temperature monitoring data, and analysis of that data, to bolster their arguments. But a new study by a team at the University of California--called the Berkeley Earth Surface Temperature project--should put those arguments to rest.
The study, released on Thursday, stated that “global warming is real” and that the world’s average land temperature has risen by about 1.8 degrees Fahrenheit since the mid-1950s. It has received broad media attention because of one of its lead authors, physicist and UC Berkeley Professor Richard Muller, has the reputation of being a skeptic about some aspects of climate science. He helped initiate the analysis to see if the claims about flawed temperature data were correct.
Muller said in an Op-Ed published in the Wall Street Journal Europe (not published in the US print edition):
When we began our study, we felt that skeptics had raised legitimate issues, and we didn't know what we'd find. Our results turned out to be close to those published by prior groups. We think that means that those groups had truly been very careful in their work, despite their inability to convince some skeptics of that. They managed to avoid bias in their data selection, homogenization and other corrections.
The new analysis shows that at least one skeptic can be persuaded by data. It’s a different story for deniers (more on that in a bit). First a little more on the Berkeley study, which set out to take a new look at supposed discrepancies and quality problems in data and data analysis from the network of temperature monitoring stations.
The Economist explains in a story titled “The Heat is On: A new analysis of the temperature record leaves little room for the doubters. The world is warming---
There are three compilations of mean global temperatures, each one based on readings from thousands of thermometers, kept in weather stations and aboard ships, going back over 150 years. Two are American, provided by NASA and the National Oceanic and Atmospheric Administration (NOAA), one is a collaboration between Britain’s Met Office and the University of East Anglia’s Climate Research Unit (known as Hadley CRU). And all suggest a similar pattern of warming: amounting to about 0.9°C over land in the past half century.
Some climate deniers have argued that the findings of these prestigious scientific bodies are flawed because the placement of temperature measuring stations—and the data from them—were suspect. Muller and his team set out to check them, using what they said was a new method.
In the Wall Street Journal Op-Ed, Muller explains:
Our work covers only land temperature—not the oceans—but that's where warming appears to be the greatest. Robert Rohde, our chief scientist, obtained more than 1.6 billion measurements from more than 39,000 temperature stations around the world. Many of the records were short in duration, and to use them Mr. Rohde and a team of esteemed scientists and statisticians developed a new analytical approach that let us incorporate fragments of records. By using data from virtually all the available stations, we avoided data-selection bias. Rather than try to correct for the discontinuities in the records, we simply sliced the records where the data cut off, thereby creating two records from one.
We discovered that about one-third of the world's temperature stations have recorded cooling temperatures, and about two-thirds have recorded warming. The two-to-one ratio reflects global warming. The changes at the locations that showed warming were typically between 1-2ºC, much greater than the IPCC's average of 0.64ºC.
You can more read more about the study and its implications in Forbes, The Washington Post, The Atlanta Journal-Constitution, Discover Magazine, in Andy Revkin’s New York Times blog, or Joe Romm’s blog at Climate Progress
Now back to the deniers. It will be interesting to see what impact the new study will have on the larger climate denier community. Denying that our climate is changing, and changing because of man-made emissions, has isolated the US from Europe and influential—and heavily greenhouse gas emitting—countries like China and India. The United States is the "one significant outlier" on responding to climate change, according to a recent global research report produced by HSBC, the London-based bank.
Let’s hope that work like that of Muller and his team at Berkeley help to change some important minds and in doing so help turn our ship of state back to the mainstream.