Effect of Temperature Increase on Real per Capita Output. In relatively hot countries, such as most low-income developing countries, an increase in temperature has a negative, statistically significant, and long-lasting effect on per capita output. Graphic: IMF

By Martin Wolf
18 October 2017
(The Irish Times) – Right, as the world goes, is only in question between equals in power, while the strong do what they can and the weak suffer what they must.”This sentence from the History of the Peloponnesian War by Thucydides is the philosophy of Donald Trump’s administration. Thus, two of his advisers, HR McMaster and Gary Cohn, wrote in May that: “The world is not a ‘global community’ but an arena where nations, non-governmental actors, and businesses engage and compete for advantage.”This amoral perspective has serious implications. In no area are global spillovers more significant and co-operation more vital than climate. The failure to act ensures that the poor would indeed suffer.This is the conclusion of a chapter on the economic impact of weather shocks, in the International Monetary Fund’s latest World Economic Outlook. The largest negative impacts of the shocks being made more frequent by global warming are on tropical countries.Nearly all low-income countries are tropical. Yet these countries are the least able to protect themselves. Thus they are innocent victims of changes for which they bear no responsibility.In assessing these risks, one has to start from the proposition that anthropogenic global warming is a reality. The intellectual industry devoted to denying this is well-funded and noisy. But its arguments are highly unconvincing. The underlying physics are undeniable.Furthermore, the empirical connection between rising concentrations of greenhouse gases and temperature is unambiguous. If little or no action is taken, average temperatures could rise by 4°C, or more, above pre-industrial levels by the end of the century. Aware of the lengthy lead times needed if effective action is to be taken, both to mitigate climate change and adapt to it (where inescapable), rational people would act now.

Effect of Temperature Increase on Real per Capita Output across the Globe. An increase in temperature has a highly uneven effect across the globe, with adverse consequences concentrated in the parts of the world where the majority of the world’s population lives. Graphic: IMF

The main obstacles to such action are three. First, specific economic interests, notably in the fossil fuel industry, are understandably opposed to action and, not infrequently, to the science that suggests it is necessary.Second, free-marketeers, who despise both governments and environmentalists, reject the science, because of its (to them) detestable policy implications. Third, few wish to inconvenience themselves, let alone threaten their standard of living, for the sake of the future, or people in poorer countries. [more]

Poorest countries suffer most from global warming