Thanks go out today to Reason.com science correspondent Ron Bailey for inspiring today’s Science 101 lesson. (Disclaimer: Ron is an acquaintance, fellow libertarian and nice guy. That said, he doesn’t always get his science corresponding correct, at least when it comes to climate.)
In Bailey’s recent column, “Will a Republican Congress Knock Science Back Into the Stone Age?” (Reason.com, Oct. 26), he writes:
The balance of the evidence is that the man-made emissions of greenhouse gases are increasing the average temperature of the globe.
Brimming with excitement upon reading this, I immediately went to Edmund Scientific’s to see if I could purchase such a scale or balance to weigh evidence. Unfortunately, I learned that I could only purchase equipment to weigh things like solids, liquids, powders and animals. The science equipment supply house had nothing for sale that could weigh evidence. No other purveyor of scientific equipment had any new or magical technology for weighing evidence either.
As it turns out, the notion of weighing evidence isn’t a scientific one at all. While courts of law have finders of fact (i.e., judges and juries) who weigh evidence and regulatory agencies employ a weight-of-evidence concept in risk assessment to help make often-politicized regulatory decisions, science is about determining objective facts and proofs, not about making hasty and subjective judgments. From Copernicus and Galileo to Brahe and Keppler to Newton and Einstein and all the other great scientists in between and since, science has always been about the search for truth about the natural world, not the search for a politically correct or viable consensus about the same.
And the way scientists determine truth is by formulating hypotheses, designing and conducting experiments to test the hypotheses, and then publicly reporting their methodologies and results so that others may verify any claimed results and conclusions. This process is then repeated as necessary to arrive at the point of objective knowledge.
That’s the theory anyway, so what about Bailey’s assertion?
We know objectively that human activity has increased the concentration of atmospheric greenhouse gases, perhaps by as much as 65 percent since the mid 19th century. We’re pretty sure that average global temperature has also increased since that time — but no one can be sure by precisely how much since we do not have a sufficient number of temperature readings from enough places covering a long enough period of time. Moreover, we also know that the available temperature data have either been significantly and artificially increased by the urban heat island effect, and/or have been extensively manipulated by collectors.
We also know that while atmospheric greenhouse gas levels have steadily risen, global temperatures have done everything but. Since 1995, for example, GHG gas levels have increased by around 10 percent, but average global temperatures have gone nowhere, perhaps even slightly down. Between 1940 and 1975, global temperatures markedly declined leading to alarm about a pending global cooling.
The question to be answered then is whether the known human GHG emissions are in any way causally related to the sort-of-observed temperature changes.
One valid way to answer the question might be to make some prediction about global temperature based on manmade greenhouse gas emissions and to see if it comes true. A similar process was used by Sir Arthur Stanley Eddington to confirm Einstein’s Theory of General Relativity in 1919. Despite the billions and billions of dollars spent worldwide on climate science over the past 20 years, this has yet to be accomplished.
Invalid ways to answer the question include mere observations of changes in Arctic melting, frequency or severity of weather events, ocean pH, coral reefs or polar bear populations. Even if such events were tied to warming global temperatures, it would still need to be proven that human GHG emissions caused the warming in the first place. Also invalid are purported historical temperature reconstructions, like Michael Mann’s infamous hockey stick. Past any fraudulent aspects to them, they offer no information about the potential relationship between greenhouse gas levels and temperature.
It is noteworthy that global warming alarmist groups like the Union of Concerned Scientists have latched onto the weight-of-evidence notion in a national advertising campaign “to educate the public about the overwhelming weight of the scientific evidence for human-caused global warming.” But an illustrative case of how UCS employs weight-of-the evidence is provided by the web site ActivistCash.com:
In 1986 UCS asked 549 of the American Physical Society’s 37,000 members if Ronald Reagan’s Strategic Defense Initiative (SDI) was “a step in the wrong direction for America’s national security policy.” Despite the biased wording of the push-poll question, only 54 percent disapproved of SDI. Even so, UCS declared that the poll proved “profound and pervasive skepticism toward SDI in the scientific community.”
Fortunately for the rest of us, Reagan’s SDI helped bring about the collapse of the Soviet Union, despite UCS’s dubious scientific consensus.
To date, Copernicus and Galileo are perhaps the most prominent victims of Bailey’s subjective method for determining objective reality. But watch out, the rest of us could be next.