What the ozone hole tells us about the science of climate change
The atmospheric sciences community is excitedly discussing new results that potentially cast doubt on our understanding of the chemistry of the Antarctic ozone hole. The ozone hole is formed when two molecules of chlorine monoxide react with each other to form what is known as the chlorine dimer, ClOOCl, and that molecule is subsequently blasted apart by sunlight to release the chlorine atoms. New results suggest that this reaction is actually much slower than previously suggested. If this is true, it suggests that there is some important chemical process destroying ozone in the Antarctic stratosphere that we do not know about.
In reaction to this unexpected scientific result, stratospheric chemists are attacking the problem, trying to think up potential mechanisms that reconcile these new measurements with everything else we know about the chemistry of the stratosphere. As a former stratospheric chemist, I can say that I have not seen this level of excitement in the stratospheric chemistry community in at least 10 or 15 years.
So what does this tell us about the science of climate change? It tells us that many of the criticisms of climate science coming from the skeptics are dead wrong.
Skeptic Myth No. 1: Scientists who don’t go along with the consensus are ostracized.
Reality: Scientists make a name for themselves by destroying the common wisdom. This new result on the ozone hole chemistry shows this. These researchers had no trouble publishing their results, and no one is attacking them for it. In fact, they are receiving tremendous positive publicity; just read the Nature article linked above. If this measurement turns out to be correct, these researchers will have made a significant name for themselves.
Skeptic Myth No. 2: The scientific community is not interested in any results that conflict with the consensus.
Reality: Credible scientific results that cast doubt on our scientific understanding of any subject are always of great interest to the scientific community. In this case, for example, many researchers around the world have jumped on this problem, trying to understand what the implications of it are for stratospheric chemistry, or to find additional data to validate the measurement. Those who solve the riddle and figure out how this new measurement fits in will also make quite a name for themselves. That is also clear from the Nature article.
Overall, the idea that any scientific community is not interested in new ideas is ridiculous. Good new ideas are the fuel that science runs on, and when new ones come out, they are thoroughly investigated by the scientific community. This new result about the ozone hole is a good example.
For those of you who might be wondering, here is what I think about this new measurement. First, it is crucial to realize that it has not been replicated. Replication is the cornerstone of science, and results that have not been replicated must be considered tentative. Second, my intuition suggests that attempts to replicate this measure will fail, and the measurement will turn out to be wrong. Before this new measurement, our understanding of stratospheric chemistry fit together well, like a completed jigsaw puzzle. If this new measurement turns out to be right, then there must be a compensating error somewhere else in our understanding. That would mean previously there were two errors, which exactly compensated in our understanding of ozone hole chemistry. While this is certainly possible, it strikes me as unlikely. However, the great thing about science is that future research will determine whether my intuition is right or not.
The other important thing to remember is that this new result does not mean that chlorine from chlorofluorocarbons is not responsible for the ozone hole. In fact, it is still highly likely that chlorine is destroying ozone. However, if this measurement turns out to be right, chlorine will be destroying ozone in a way that we do not presently understand.