It seems very fashionable at the moment to cast doubt on the science associated with climate change, even to argue that there is some global conspiracy amongst the thousands of scientists working with the data to mislead us, to coerce us into changing our lifestyle, and to excessively govern our actions. Such an action is of course seen as a violation of our rights, and we are encouraged to become indignant and hostile to it.
Of course, everyone acknowledges that there is something going on with the weather, that the polar ice caps are losing some of their ice, that the sea is warming up, and that the carbon dioxide level is increasing in the atmosphere. Many also concede that weather systems seem to be becoming rather more unstable and accept that there has been an increase in the number of serious hurricanes, tornadoes, floods, droughts, and violent storms. And yes, it's true that habitats are disappearing leaving some species on the verge of extinction.
But, the argument goes, it's just a natural process, something that happens to the world in cycles, and we'll just need to ride it out and everything will be fine again. For every piece of research or data that shows the seriousness of the problem, there appears to be someone else willing to say that the science is either wrong or insufficient. The idea of doubt in the data is a very powerful mechanism for getting people not to believe any of it.
But let's think about that doubt for a moment. Science is of course full of doubt: if there weren't doubt, science would just stop. Scientists are driven by doubt, by wanting to understand things fully, and in the case of climate change, no scientists would be satisfied that they had all the data they wanted. But doubt doesn't at all imply that the data is inadequate to inform a decision. We can have sufficient data to be sure of the right thing to do, long before we have sufficient data to say we fully understand the problem.
Think about going to the doctor. How would it be if the doctor said he wouldn't treat you until he was 100% certain of what was wrong with you. He would embark on a long series of exhaustive tests, and each time he had the slightest doubt, he would insist on doing more. He would discover that there were certain cycles that occurred in the human body and explain away symptoms as nothing to worry about, just a natural consequence of being human. As the symptoms accumulated though, he would find it difficult to explain everything, but being resourceful he would come up with more and more theories to test out. Meanwhile, you are still ill, and getting worse, but that's OK because you are now providing more and more symptoms for the doctor to analyse. Of course he would only be really sure of his results at the autopsy.
Fortunately, medicine doesn't work like that and neither does climate science. Doubt and skepticism about the results are really important drivers of the scientific process, but so are responsibility and the willingness to draw conclusions. We cannot dismiss the accumulated evidence of climate change caused by global warming, and now most people, even politicians, accept that it is reality.
So what about the causes? Well there have been argument, discussion, debate and challenges among the climate scientists for more than a decade, with theories counterposed and evidence attacked and defended. That's the way science works. It simply isn't the case that the scientists all came to the same conclusion and agreed to promote it. There was an enormous struggle among scientists over years and years offering different theories and recommendations. That's what drove the research.
There were theories and rows about the Milankovich cycles, about solar activity, about which, if any, carbon sinks were important, about the changes in the Gulf Stream, about patterns of El Niño and La Niña, about alternative greenhouse gases, about the accuracy of the climate record, from tree rings to ice cores, about the heating currents in surface waters, about methane and water vapour, about medieval warm periods, about changes in agriculture and industry, and more and more and more.