About a week ago, NOAA (the US National Oceanic and Atmospheric Administration) reported news from their longest-running atmospheric measurement station on top of Mauna Loa, Hawai’i: The average daily concentration of carbon dioxide in the atmosphere passed 400 parts per million (ppm) for the first time. This level was already reached a year ago in Barrow on the Alaskan north coast, and it is expected to take a few more years for global averages to rise to this number.
The symbolic milestone led me to reflect on the messed-up state of the public debate on global warming and climate change, and its chances of moving into a saner state any time soon. I appreciate that people differ in their political attitudes and preferences about what actions should be taken, which I may agree or (strongly) disagree with. People may also pursue different goals, and that these may be in conflict between individuals. When it comes to discussing matters of fact, however, it should not be impossible to have a common ground on to lay them out and examine them, even if we end up drawing different conclusions or giving different weight to one over the other. Clearly, when it comes to the human impact on the earth’s climate and climate science in general this is very far from being the case.
When dealing with a scientific topic, only few people operate at the level of expertise to have a first-hand informed opinion on the current state of knowledge. Not that few, actually, but few compared to the size of the public as a whole. The rest of us rely on our general scientific background to evaluate what the specialist say, and on translators such as science writers, science educators and researchers from other disciplines to help fill gaps in understanding, link back to more basic knowledge and check that published results pass tests of plausibility. Another tool we use to figure out what factual statement we hold to be true is, I think, to be found in each individual’s biography: We build our mental model of how the world works incrementally. This is the case for judgements (what is important or not, what are the bases of my ethical guidelines etc.) just as much as for facts, and they intermingle. It is in this regard that I wonder about how the experience of the so-called denialists may contrast with mine.
Because it’s pretty much inconceivable to me how, having lived through similar times as myself, someone would end up believing that human activities are not causing changes to the global climate in a way that is worrisome. [Skip to part 2.]