A few years back, I challenged the traditional "conservative" or "libertarian" approach to global warming. I wrote:

The scientific debate over global warming is not so much over whether anthropogenic emissions will affect the climate. Rather it is over the nature and magnitude of the likely effects. Even the most ardent global warming skeptics within the scientific community believe that the increased accumulation of greenhouse gases in the atmosphere will have some effect. The policy question, then, is what (if any) measures are justified to prevent or mitigate such effects.

Most on the "right" argue that the best response is to do little or nothing. While some advocate various "no regrets" policies to improve the efficiency of energy markets (and perhaps pave the way for alternative fuels) -- as I did here -- few conservatives, libertarians, or other free-market advocates believe the most reliable climate forecasts justify drastic measures to suppress the use of carbon-based fuels. The costs of such measures, many argue, are likely to swamp the costs of climate change, and more direct measures to address global ills that could be exacerbated by climate change (disease, flooding, weather extremes, etc.) would be far more cost-effective than reducing greenhouse gas emissions.

As an analytical matter, these assessments are probably correct -- it is hard to justify one Kyoto on economic grounds, let alone the dozen or so that would be necessary to stabilize greenhouse gas concentrations in the atmosphere -- but that does not mean the proper "free market" climate policy is to "do nothing."

If property rights lie at the heart of free market environmentalism (FME), then FME advocates should think seriously about the normative implications of human-enhanced climate changes that could disproportionately harm those portions of the world that have (at least thus far) contributed least to the problem. Even if a modest warming were, on balance, beneficial, the impacts would not be uniform. It may well be, as some argue, that increases in crop productivity and reduced energy costs in temperate regions will be greater than the costs to tropical regions, but this does not address the property rights concern absent some system whereby industrialized nations would compensate or indemnify less-developed nations. No such system exists -- nor is it likely that existing international institutions could implement such a system -- but that does not mean it would not be the first-best approach to climate change from an FME perspective.

Various folks, from Tyler Cowen to Brad DeLong to Carl Pope, responded favorably to this approach. My FME allies, not so much.

This week, the Reason Foundation is hosting a roundtable on the issue, featuring an exchange between me ("Climate Change As If Property Rights Mattered") and my friend Indur Goklany ("Climate Change: No Harm, No Claim"), with an introduction by Shika Dalmia. Ronald Bailey comments on Hit & Run here. I'll also be drafting a response to Goklany in the next few days.