I have mentioned Judith Curry’s ‘Climate etc’ blog before with approval, and I’ve used an idea in a recent blog of hers as the subject of today’s essay. She took a question from Andy Revkin, who writes about climate and other environmental matters for the New York Times: ‘What do you see as the best mix of achievable policies to limit environmental and economic regrets?’ He asked it in the context of global warming. She thought it was an excellent question, and invited her readers to respond. So far 641 have done so.
I too think it is a good question, and it is indeed at the heart of the policy debate about global warming. I haven’t posted my response yet, and this essay is a way for me to formulate it. In answering that question any of us has to first of say what he or she thinks is the likely outcome of the kind of warming we have seen for the past 150 years.
My short statement goes like this. It is almost certain that by adding carbon dioxide to the atmosphere through burning fossil fuels (and through land clearance and other activities, like making cement) human beings are helping to warm the atmosphere. The data are not very good, but it looks as though this has been going on for the past thousand years, though much faster since the Industrial Revolution, when the world’s population began to rise rapidly and use fossil fuels much more systematically.
How much of the warming is due to what humans do? We don’t know. On the evidence it could be only a little. It is probably not much more than half, if it is that much. Should we be worried about it? Only if the warming accelerated rapidly, and so far this seems unlikely. What about the prophesied rise of the oceans? Again, on the evidence, the oceans have been rising at an average rate of about 3mm a year for many centuries, and the 21st doesn’t yet seem to be an exception.
You will conclude from this statement that I am not at the moment worried by global warming, and that would be true. Again, on the evidence, warming has occurred in the past and is likely to continue to occur. Some parts of the world greatly benefit from warming, and more warmth plus more carbon dioxide is good for food production, so that in principle we all benefit.
But I am a lukewarmer. I do think that we have an effect, and the evidence does not suggest that more warming must mean that everything gets better everywhere, all the time. Mind you, just about everything that we think we know about the future of climate is based on the outcome of computer models, and they have a lot of improvement ahead of them if they are to be really useful.
So I would offer the following as my best mix of policies to limit both environmental and economic regrets.
(1) Use research funding in particular to explore what is meant by ‘natural variability’, with a view to knowing much more explicitly why climates change.
(2) With the aid of such new knowledge, try to distinguish the effects of greenhouse gas emissions from natural variability.
(3) Apply more research funding to increasing the efficiency of solar energy, especially in how best to store solar energy for later use.
(4) Desist from the assumption that the burning of coal is harmful. It is the best source for baseline grid power, and there are better uses for oil and gas.
(5) Get rid of carbon taxes and their like.
(6) Put more research funding into later-generation possibilities in nuclear energy.
(7) Invest more in adaptation and preparation with respect to known climatic events that are harmful to human societies, like droughts, fires, storms and floods.
(8) Restructure the IPCC so that its core business is not issuing wake-up calls to governments that are based on over-confidence about rubbery data and immature climate modeling.
I think eight policies are enough for the moment!