According to Richard Muller,Â a physicist and former climate change sceptic, humans are â€œalmost entirely the causeâ€ of the earth warming by 1.5C over the past 250 years.
Muller, who is also founder of the Berkeley Earth Surface Temperature (BEST) project, has stated that he was â€œnot expectingâ€ the results he received from recent findings. â€œAs scientists, it is our duty to let the evidence change our minds.â€ The evidence he has gathered has led him to call himself a â€œconverted sceptic,” with his views on global warming going through a complete turnaround in a short period of time.
According to the results of Mullerâ€™s study, which he discussed recently in an op-ed for the New York Times, the â€œaverage temperature of the Earthâ€™s land has risen by 2.5F over the past 250 years, including an increase of 1.5 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.â€
The University of California, Berkeley research team gathered 14.4 million land temperature observations from 44,455 sites around the world, dating as far back as 1753. Previous research by NASA and other organizations has only gone as far back as the mid-1800s.
In addition, $150,000 of the projects funds were provided by the Charles G Koch Charitable Foundation, the primary backer of the not always civilized Heartland Institute climate change sceptic group. $100,000 more was received by the Fund for Innovative Climate and Energy Research, created by Bill Gates.
The BEST team had previously published study results indicating the average global land temperature has risen by 1C since the 1950s, but did not mention any explanations for these changes. This recent data goes much further back in time, also searching for causes of rising temperatures. They analyzed solar activity, one of the biggest theories among sceptics, and found that the sunâ€™s contribution to climate change is â€œconsistent with zero.â€
According to Muller, the best match in his findings was from atmospheric carbon dioxide, measured from samples in the atmosphere and air trapped in polar ice sheets. He says it is â€œcurrently the best explanation we have found, and sets the bar for alternative explanations.â€
One of the best parts of all of this is that in an attempt to maintain complete transparency with climate change sceptics, the results were released publicly before a peer review by the Journal of Geophysical Research took place.
You can view the results on BESTâ€™s website, but the gist of it is that the numbers suggest there will likely be 1.5 degrees of warming over the next 50 years, but if China stays on the same path of economic growth and coal use, it could be less than 20 years before this happens.
Muller has also said he hopes his analysis will â€œhelp settle the scientific debate regarding global warming and its human causes,â€ and that it may help in creating agreements across the political spectrum, making more room for solutions and less time for disagreeing over the numbers that already exist.
Pretty telling stuff. Do you think this will lessen the remaining small yet vocal climate change debate, or are some sceptics always going to be sceptics, no matter what climate science brings to the table?
Image CC licensed by Tom Raftery: NASA Climate Data