Sitting in the sun on a holiday weekend is a chance to reflect on one of the oddest questions in economic geography. Why are hot countries poor? If you want to live both in a prosperous country and in the tropics, your choices are more or less limited to Singapore and the far north of Australia.
Sitting in the sun suggests one answer. If your home is in Manchester or Düsseldorf, there are fewer distractions from work. You are not tempted to laze around in a square with friends and drinks, nor are you frustrated by the debilitating heat and humidity of many tropical regions. Yet it is not so cold that much of your time, energy and income is devoted to keeping warm. The work ethic is easiest to maintain in drizzle and a light breeze.
Attempting to escape this moralising argument, Jeffrey Sachs has emphasised disease: hot, humid climates may not be congenial environments for humans but they are congenial to many unpleasant parasites. Malaria alone is a major obstacle to economic development. Another geographic explanation comes from Jared Diamond. The crops and animals on which modern agriculture is based – such as corn, pigs and sheep – thrive in temperate zones. In an ingenious twist, Prof Diamond argues that this is why Eurasia – a horizontally positioned land mass where agricultural practices could be transmitted to similar climates to the east and west – developed more readily than America, a vertically positioned landmass in which agricultural practice could not easily be transmitted from north to south.
This European good fortune leads to a different explanation that relies on the influence of European colonialism. In their 2001 paper, The Colonial Origins of Comparative Development, Daron Acemoglu, Simon Johnson and James Robinson of MIT point out that you would have seen a very different relationship between temperature and per capita income if you had looked at the world in 1500, when the Mogul and Aztec civilisations were at their height. But then western Europe developed the political, social and economic institutions that make modern economic prosperity possible – and in subsequent centuries transmitted these around the world.
The effects of transmission through settlement were very different from the effects of transmission through colonisation. If you are going to seek a better life, the most attractive location is a place slightly (but not much) warmer than the one you are used to. That is why I am writing this in the south of France – and why migrants of European origin settled in southeast Australia, New Zealand, South Africa and the US, taking their institutions with them.
The explanation for European good fortune relies on the influence of European colonialism
But in India and the Congo Europeans had no interest in permanent settlement: the institutions they installed were those of exploitation, and a legacy of exploitation continued to afflict these countries even after the colonisers departed. It is not an accident that Montesquieu was the first person (in 1748) to observe the correlation between climate and prosperity: not only was he from a colonial power, but he was writing at precisely the time that imperialism was creating the phenomenon he described.
These factors are interdependent. Malaria is no longer a problem in Italy and the southern US but that is not because Italy and the southern states no longer have climates susceptible to malaria: it is because they have the public institutions needed to eliminate the problem. Modern agriculture is most successful in temperate zones but that is because the crops that have been most effectively bred are those adapted to climates with the most advanced agricultural technology. Singapore could neither prosper without air conditioning, nor afford air conditioning without first achieving a measure of prosperity.
And it is these interdependencies that make poverty such an intractable problem. Prosperity is associated with honest, stable, institutions, the effective use of modern technology, a functioning transport and communications infrastructure, satisfactory public health and hygiene, and many other things. To establish one of these without the others achieves little. That is why attempts to kick-start economic development have mostly failed: countries must find their own paths to prosperity. Today there are some hopeful signs that more states are achieving precisely that.