Scientific Consensus

Last time, I published my reply to a climate change doubter. In it I stated that it is not difficult to find support for any position if you search the internet. However, as a friend recently pointed out, the validity of a position or opinion must be weighted by credible evidence, and agreement with that evidence by the greatest number of credible experts. It is the kind of evidence that allows us to state as fact that the sun is the center of our planetary system and that it is 93 million miles from Earth, even though none of us is likely to have ever checked it out for ourselves. We have complete faith that science has ferreted out the truth.

I remember talking about climate change back in the 1980’s with a friend of mine, Steve Hodge, a glaciologist then working for the US Geological Survey. At the time, there was a vigorous debate among scientists around world as to whether climate was in fact warming and, if so, if it could be attributed to human activity. It was several years later, in 1988, that he told me that a consensus had been reached that climate was warming and that it was most likely caused by humans.

It is a tribute to the rigorous search for truth by thousands of scientists applying the scientific method that another 13 years had passed before an official statement was made. In 2001, the Intergovernmental Panel on Climate Change published this statement:

An increasing body of observations gives a collective picture of a warming world and other changes in the climate system... There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities.

The main conclusions of the IPCC on global warming were the following:

The global average surface temperature has risen 0.6 ± 0.2 °C since the late 19th century, and 0.17 °C per decade in the last 30 years.

There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities, in particular emissions of the greenhouse gases carbon dioxide and methane.

If greenhouse gas emissions continue the warming will also continue, with temperatures projected to increase by 1.4 °C to 5.8 °C between 1990 and 2100. Accompanying this temperature increase will be increases in some types of extreme weather and a projected sea level rise. On balance the impacts of global warming will be significantly negative, especially for larger values of warming.

According to Wikipedia, "Scientific Opinion on Climate Change", there is today no scientific body of national or international standing that maintains a dissenting opinion to this statement. The last was the American Association of Petroleum Geologists which in 2007 updated its position rejecting human influence on climate change to the present one of non-committal. I can’t find the exact source of this statement, but would appreciate hearing from anybody that can disprove it.

Science seems to be one of the best systems we have developed for "knowing" things. It is designed to eliminate the influence of bias or preconception. To maintain its credibility, all findings are subjected many times over to rigorous review by disinterested peers. Only in this way would we have been able to reject the long held intuitive belief that the Earth is flat and the center of the universe. If you don’t trust the overwhelming scientific consensus about climate change, what system of "knowing" are you using? Is it really so good that you are willing to buck the consensus and ignore its warnings of dire consequences for everything you hold dear.

I think the real playing field is not the rational analysis of science but in the realm of belief and intuition. For 5000 years, we have been on a campaign to master nature. About 50 years ago, some began to introduce the idea that the master to slave relationship needed to change to one of dancing partners where we would lead nature in a collaborative way into the future. More recently, many are beginning to believe that perhaps we shouldn’t be the leading partner in this dance. This is a subtle change but deeply disturbing to many. It’s one thing to accept that Earth is not the center of the universe, but to be expected to accept that man is not central and sovereign on this planet is very difficult to swallow. Meanwhile, the master to slave paradigm continues to predominate. Never has there been a more important time to carefully weigh the facts and act.

Climate change doubters, please consider this analogy: You are crossing an apparently sturdy bridge and are told by a very reliable source that in fact the bridge would very likely fail and send you into the abyss. If you don’t use the bridge as is, you fear that someone else will, and will beat you to a customer you were hoping to make a sale to. If you spend the time and money to shore up the bridge, you will lose the sale. If you take your chances on the bridge you stand a very good chance of losing your life, and, of course, if the bridge fails, nobody gets to make a sale. What’s your choice?

terry@vashonloop.com