There was a really interesting article in Physics Today this past October on the parallels between the slow acceptance of the idea of anthropogenic climate change and of the idea that the earth circles the sun.



Author Steven Sherwood writes that:

“Many who are unwilling to accept the full brunt of greenhouse warming have embraced a more comforting compromise reminiscent of the Tychonic system*: that CO 2 has some role in climate but its importance is being exaggerated. But accepting a nonzero warming effect puts one on a slippery slope: Once acknowledged, the effect must be quantified, and every legitimate method for doing so yields a significant magnitude. As the evidence sinks in, we can expect a continued, if slow, drift to full acceptance. It took both Copernicanism and greenhouse warming roughly a century to go from initial proposal to broad acceptance by the relevant scientific communities. It remains to be seen how long it will take greenhouse warming to achieve a clear public consensus; one hopes it will not take another century.”

A really important point is that what Sherwood is talking about here is not about acceptance of anthropogenic greenhouse warming within the scientific community — that acceptance has already happened — but amongst the general public. Of course, the analogy with Copernicus is still a good one, because it did take some time for understanding of the greenhouse idea to really take hold within the scientific community. Indeed, it has only been in the last year that the American Physical Society (APS) has considered climate change a central-enough topic to deem it worthy to start a climate change ‘topical group’. (The APS topical groups are formal, structured discussion groups that have to be approved by APS. Note for those that might think politics might have played a role in slowing things down: this most certainly isn’t the case. The APS leadership is simply very conservative about what is deemed central enough to Physics to approve a topical discussion group; for example, a colleague of mine spent several years trying to convince APS to support such a group on Quantum Information. That climate change is now an APS focus group topic makes a strong statement, but not a political one: it simply reflects the maturity of the field. Members of APS that are interested in climate should consider joining; there are bound to be some very interesting discussions in areas such as radiative transfer and atmospheric dynamics.)

Sherwood’s article deserves to be widely read. It is freely available on the Physics Today web site.

For more on the history of of the development of the greenhouse idea within the physics community, our own Ray Pierrehumbert’s article in Physics Today (pdf) is also a very worthwhile read.