It’s been interesting to see the different responses to the Paris agreement. James Hansen calls it a fraud (Richard Erskine thinks he’s wrong). Kevin Anderson is a bit more measured. Others are more positive and optimistic.

I find myself sympathysing with most of the views, both positive and negative, but leaning more towards thinking this is a positive step, at the moment at least. One obvious problem is that the agreement makes strong statements about limiting warming to well below 2oC, or possibly even 1.5oC. However, doing so would require getting net emissions to zero very soon, or relying on negative emissions sometime in the future, even though such technology is as yet largely undeveloped and may be potentially risky. Yet, there is little concrete discussion as to how we would do so, and little sense that we will see emission reductions in the immediate future. So, I can see why some are rather negative.

On the other hand, getting so many nations to actually sign up to such an agreement, and to endorse such strong statements, is quite impressive. It may not be as much as many would have liked, but it’s more than some were expecting. Scientists may have a strong sense of what is required to achieve the stated targets, but that doesn’t mean that it’s easy to convince everyone, or that it would be easy to achieve even if people did agree. Societal/political reality requires more compromise than scientists may be used to when discussing scientific issues. Just reaching agreement is a form of progress in itself.

Of course, we should probably have reached this kind of agreement 10 or 20 years ago. However, as all scientists should know, we can’t go back in time. That this agreement might, according to some, be 10 or 20 years too late, doesn’t really change that it is probably a positive step, given where we are now. It may still not be enough, and we may well regret not having done more, but I doubt any amount of gnashing and wailing will change anything. We have to start somewhere, and that so many nations have endorsed such a strongly worded agreement at least suggests that they recognise the issue, even if they haven’t really provided a clear way in which to achieve the targets. Even if it all seems a bit too slow, I probably agree with Joe Romm who says

Change happens slow, until it happens fast.

I hope he’s right, though, that we have indeed entered the fast phase.