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Berkeley Earth Surface Temperature (BEST)

Berkeley Earth Surface Temperature (BEST) is a large-scale, multi-study project funded by the Novim Group at the University of California Santa Barbara (UCSB) and run both at UCSB and at UC Berkley. The study is famous for being headed by Richard Muller, a former skeptic of climate change, and for being funded, in part, by Charles Koch, who is heavily invested in petroleum industries.

BEST has five basic objectives, but they can all be summed up as an effort to resolve discrepancies in climate data that make some of it unreliable. Specific objectives are:

  • To merge surface temperature data sets into a comprehensive raw data set that has a common format
  • To develop statistical methods that remove limitations affecting previous algorithms and to ensure those methods can accommodate the quantity of data in the set
  • To publish a new global surface temperature record that incorporates an analysis of the uncertainty in the data
  • To publish all data, software, and other tools to provide an open platform for discussion and research
  • To post all findings and papers online so as to make them freely available to all. This will include the allowance of comments on the data and methodology used.

Results and Reception

Though BEST is an ongoing project, initial results from more than 1.6 billion measurements dating back to the 19th century found the following:

  • Previous concerns about poor measuring equipment and about urban heat islands did not seem to bias results. Therefore BEST has confirmed findings from earlier studies such as those carried out by the National Oceanic and Atmospheric Association and NASA.
  • The warming trend from previous studies was confirmed in 2/3 of data sets, even though cooling was seen in the other 1/3.
  • The overall warming trend appears to be confirmed
  • The Atlantic Multidecadal Oscillation ( a climate index) appears to play a very large role in global temperature trends.

The project was controversial from the beginning, in particular due to the funding by Koch. Climate scientists were skeptical that Robert Muller would remain neutral during his research, especially since he was already skeptical of claims about climate change. For these reasons, the confirmation of previous research by the BEST project came as a surprise to many.

One of the biggest criticisms of the BEST project so far has been the fact that thermometers and temperature stations only a few miles apart demonstrate very different trends over the 70 years of data in the study. In fact, most of the Southern and Eastern United States shows both a cooling and a warming trend, something that is not well-addressed by the study. The basis of the argument is that if large regions are showing both warming and cooling, how can we be certain that any of the data collected is accurate?

The fact that 70 years worth of data were used is also seen as a potential source of error by some who claim that reliable data can only be had for the previous 30 years. This is probably the biggest criticism of the study because extending models back to 70 years may bias trends if the temperature from those periods was actually higher or lower than what is recorded. In other words, the only reliable trend that can developed from instrument data cannot date further into the past than about 30 years when it is well established that instruments were reliable, well placed, etc.

On the supporting side of the study, researchers from NASA and from the University of East Anglia have stated that the confirmation of previous studies using new techniques and larger data sets is proof positive that the climate is warming. They further point out that the strong similarities between BEST and previous projects are more evidence in favor of anthropogenic global warming and that the use of different methods that reach the same conclusion as others supports the original data.

Despite his findings, Muller has stated that even with the confirmation of previous studies, it is important not to buy into the speculation surrounding future climate changes. He suggests that many claims are exaggerated and that climate alarmists are doing more harm than good to the science of climatology in general.