Answering Tamsin Edwards’ Important Question

Climate modeler Tamsin Edwards is one of the sanest people involved in public discussions of climate change. She gets it. She doesn’t demonize, she engages. She doesn’t rant, she discusses.

Ms. Edwards has an article up on the Guardian that I saw courtesy of Judith Curry’s excellent Week in Review series. I used to try and do a weekly review–now I don’t have to.

Ms.Edwards’ article is about Lukewarmers and it is good. Not perfect–she gets some things about us wrong, but overall it is a credit to her.

Her article ends with a question for Lukewarmers and I want to provide an answer. She writes, “If you agree with mainstream scientists, what would you be willing to do to reduce the predicted risks of substantial warming? And if you’re a lukewarmer, confident the Earth is not very sensitive, what would be at risk if you were wrong?”

As a Lukewarmer we have the added risk of being wrong in two directions. If the Lukewarm position overstates coming warming, our focus on no regrets policies, technology transfer and the revenue neutrality of the carbon tax I advocate minimize the risk of huge overspending on warming that doesn’t occur.

But somehow I don’t think Tamsin was thinking of that direction to our potential error.

If we underestimate upcoming warming what are the consequences?

I submit that the path to emission reductions almost has to start with the policy preferences Lukewarmers endorse. Indeed, many of our policy preferences are actually votes in favor of continuing policies that predate the Lukewarmer position, such as a focus on energy efficiency. Governments are investing in innovation in energy generation and storage. Technology transfer is taking place.

True progress on mitigation is likely to take most of the rest of the century to achieve. Even if it were today determined that more aggressive action is required to combat climate change because it is ‘worse than we thought’, the first actions taken are likely to be actions Lukewarmers propose. Just as with energy efficiency, climate change mitigation would begin with the low-hanging fruit.

For example, I heartily endorse the actions described as Fast Mitigation, especially chasing after black soot that changes the albedo of the Northern Hemisphere by graying up snow. If you imagine Paris coming up with a treaty that magically authorizes a command and control response to global warming starting today, it still makes sense to go after black soot and the other Fast Mitigation policies first. Fast Mitigation reduces forcings by 0.5C this century while top down emission control policies would only reduce forcings by 0.1C.

In a sane world we would beef up the things we are doing that are working in parallel with new activities.

So if instead the Paris conference on climate change mistakenly votes for a Lukewarm view of climate change and climate change proves to be higher than we think–and that is a possibility–then we will have merely started down the road that Paris would lead us down if the Alarmist view had won the day. But we would have done it more quickly and quite possibly more cost effectively.

I hope Tamsin Edwards keeps coming up with more intelligent commentary and intelligent questions for Lukewarmers. We need to be challenged on our premises more frequently. Precisely because we are in the middle of the food fight between skeptics and alarmists (we participate in the food fight too, I’m not suggesting we are somehow above the fray), it is easy to say that because we are attacked by both skeptics and alarmists we must be doing something right.

While I hope that’s true, it’s not a given. The skeptics and alarmists could both be wrong and we could be as well. We could easily all be wrong. That’s why the discussion is still important in 2015.