I’ve been rather busy the last few days, so haven’t had a chance to post anything. Yesterday, however, Judith Curry gave evidence before the House of Representatives Committee on Science, Space and Technology Hearing on the President’s UN Climate Pledge. You can read Judith’s written evidence. It contains most of the standard “skeptic” talking points; the “pause”, Antartic sea ice, lower climate sensitivity, and then a lot of discussion about climate policy.

Steven Mosher, in a comment on an earlier post, gave his interpretation of Judith’s argument, and finished with

Now in truth you dont even need her views on science to come to a similar conclusion. with regards policy, science dont matter much. what matters is what you can get done. you’all got suckered into thinking that speaking truth to power worked. Sorry no cookie. The time to act globally on emissions has come and gone. Its been 20 years and you clowns still havent done jack. step aside. you are the problem.

Okay, ignoring that I disagree with a great deal of this (and find some of it remarkably irritating) there is some truth to this view: in some sense science doesn’t matter that much, and what we’ve been doing so far hasn’t been particularly effective. So, maybe it is time to at least compromise and start to accept that there are other ways to proceed and that what we’ve been trying to do hasn’t worked? If, however, there are to be new people who drive this forward, surely we’d want them to be those who at least understand the basic science and who can at least construct a coherent argument.

On that note, I thought I might just highlight an exchange between Judith Curry and Rep Beyers in which he explicitly says

I found myself deeply troubled by Dr. Curry’s written and oral testimony, ….. I found the testimony just full of internally conflicting facts and opinions and in almost total conflict with everything I’ve read in the last 15 years in every journal I could get my hands on.

You can read the comment yourself, but I thought I might just discuss a few of Judith’s responses. For example,

The issue is how much of the change is caused by humans. We don’t know. We don’t know what the 21st century holds. The climate change may be really … unpleasant, and that may happen independently of anything that humans do. My point is that we don’t know how much humans are influencing climate and whether it’s going to dominate in the 21st century. Given that we don’t know this, we are still going to see extreme weather events whether or not humans are influencing the climate.

We don’t know? Really? This may only be true in the sense that we can’t really know anything, but that is a remarkably odd thing for a scientist to say. We may not know, but we’re fairly certain that anthropogenic influences have dominated since 1950 and that it will continue to dominate if we continue to increase our emissions. That Judith failed to even acknowledge this is remarkable. Also, we have plenty of evidence to suggest that our climate has been broadly stable for the last few thousand years. Why would we suddenly expect it to naturally do something unpleasant in the coming century. It might, I guess, but suggesting that it’s as likely as something unpleasant happening due to our influences just seems absurd.

Judith then goes on to say

The climate has been warming since the 1700’s. Okay? Since we came out of the Little Ice Age. We don’t know what’s causing that warming, in the 18’th century, in the 19’th century, it’s not attributed to humans. So there are other things going on in the climate system that have been contributing to a warming over several centuries. We can’t blame all of this on humans. Okay? And we don’t know how all of this is going to play out in the 21’rst century. We just don’t know.

Again with all the we don’t knows. Yes, we might not know but we have a pretty good idea of what caused the Little Ice Age (reduced solar insolation and increased volcanic activity) and it was obviously not attributed to humans. Why is that even worth mentioning? Again, we might not know what will happen in the 21st century, but we have a fairly good idea of what will happen if we continue to increase our emissions.

So, if we’re going to move forward by acknowledging that what we’ve been trying so far has failed and that others should have a stronger voice, why would we do so if some of those others don’t appear to know anything? Given this, I’ll expand a little on my thoughts with regards to Mosher’s point that with regards to policy, science doesn’t much matter. Yes, in some sense I agree with this; let’s stop arguing about science and just get on with deciding on the optimal policies. However, science does inform policy and I fail to see how we can develop sensible policy if we start with the view that we don’t know anything.