President Obama and his administration take pains to stress that their climate and environmental policies will be informed by the best science available. And that is as it should be, but the entire task can be complicated by the fact that sometimes the best available science may not be good enough for the task at hand.
Anthony Watts’s report on the Surfacestations project—Is the U.S. Surface Temperature Record Reliable?—raises the distinct possibility that critical portions of policy-relevant climate science may be based on questionable, if not bad, data. And good science cannot be founded on bad data.
The Surfacestations project, initiated by Watts, is a survey of the 1,221 surface temperature stations that make up the U.S. Historical Climatology Network, a survey conducted by 650 volunteer citizens. This Network was established by NOAA to provide, among other things, accurate and unbiased long-term temperature trends for the United States.
Watts’s report is based on a survey of about 70 percent of the sites. It provides photographs and other documentary evidence that NOAA’s own siting standards have been not only compromised, but badly compromised. Many of these monitors are today located in airports and wastewater treatment plants, which are hardly representative of the earth’s surface. More importantly, over the years, towns and cities have grown around the monitoring sites, the immediate vicinity of the thermometers has been paved over with concrete or black asphalt, heating and air conditioning units have been introduced, and shade-providing trees have grown up or been chopped down. Most of these changes would tend to exaggerate the degree of warming that has occurred in the United States (and globally).
In other words, the U.S. surface temperature record is not reliable for making quantitative estimates of long-term temperature trends (although it may be possible to infer whether or not there has been some unspecified amount of warming). And if the temperature record from the United States, with its vast resources, is unreliable, so in all likelihood is the temperature record from most other countries (e.g., China, Russia, India, Brazil, and Mexico which cover large tracts of the globe but have historically lacked adequate resources and/or have been subject to internal discord and instability that can compromise data collection). In other words, the global surface temperature record is also unreliable. [This may also explain why the warming trend is stronger for surface data—the trend that the Intergovernmental Panel on Climate Change (IPCC ) uses for its reports and projections—than for satellite observations (for the period during which the two sets of records overlap).]
And if the surface data are compromised then so is everything that relies on that surface data, including:
· Quantitative estimates of the degree and rate of warming that has occurred in the past,
· Climate models that were constructed using this data,
· Results generated by those models, including what proportion of the warming may be attributed to well-mixed greenhouse gas emissions and projections of future climate change, and
· Benefits from any future reductions derived by using those models.
So while I wholeheartedly support the desire to use the best science in our decisions, it is equally important to ensure that the best science is, in fact, good science. Unfortunately, good science cannot be based on bad data.
And so long as the issues raised by Watts’s report are unresolved, there will be a cloud over climate-change science.