Climate Policy and Self-Interest
TO UNDERSTAND HOW justice and ethics apply to climate change, it is useful to consider the major alternative: selfinterest. What should we do about climate change if we act purely to save our own necks?
I will seek to show here that, under almost any plausible assumptions about climate change, it is in our self-interest to start reducing emissions now, on a global basis, and to reduce emissions to near zero in the not-too-distant future. This conclusion is robust to a broad range of assumptions about the science and the economics of climate change. It follows solely from the simple self-interest of people who are alive today, their children, and their grandchildren. It holds, and is possibly strengthened, when we consider the uncertainty we face about the harms from climate change and the costs of avoiding these harms.
There are five main points that together establish this conclusion:
• Net emissions must eventually be reduced to zero or near zero because temperatures keep on increasing as long as emissions are positive, and because there is a limit to tolerable temperature increases.
- • The time limit is not too far off. While there is great uncertainty about the appropriate limit on temperature increases, most mid-range targets will be reached by the middle or end of this century, during the lives of people alive today, their children, and their grandchildren. If emissions are not reduced to near zero, these individuals, people living today and their immediate relatives, will suffer. Climate change might have primarily been a long-term problem when negotiations began in the early 1990’s, but because emissions have increased rapidly since that time, it is now also a medium-term problem.
- • Near-zero emissions in the not-too-distant future means we have to start reducing emissions now. The reason is that reducing emissions to zero or near zero means replacing the global energy system, which is currently based on fossil fuels. Replacing the global energy system is an enormous task. The system is vast, probably the largest and most complex system humans have ever built. We have been building it for more than one hundred years. The only feasible way to replace it is to start now or in the near future.
- • Reductions have to be global. Zero emissions means zero. Nobody will be able to emit carbon dioxide, including people in developing countries. Developing countries are installing a massive new fossil fuel infrastructure. If this installation continues, it will make achieving zero emissions in the relevant time frame difficult or impossible. Both developed and developing countries have to start reducing emissions now or in the near future.
• Uncertainty about the effects of climate change strengthens these conclusions because the uncertainty is not symmetric: if we do nothing or act too slowly, the bad cases if things turn out worse than expected are far worse than the good cases are good if things turn out better than expected.
These conclusions sound stark, almost extreme, when compared to the glacial pace of climate change negotiations. They are not, however, based on unsupported apocalyptic visions of extreme environmentalism. They are, unfortunately, based on conservative assumptions.