Costing the Earth
Bjorn Lomborg’s climate change calculus is profoundly flawed. Letter to The Times from George Monbiot, 18th May 2004
Bjorn Lomborg challenges me to respond to his contention that the cost of curbing carbon emissions is comparable to the cost of global warming itself, and that the money would be better spent elsewhere. He hardly makes it difficult. His methodology and his presentation of the figures are both profoundly flawed.
Lomborg begins by deliberately choosing the most optimistic assessment of the likely damage caused by climate change, and the most pessimistic estimate of the expense of minimising it. This latter figure appears to count the costs but not the economic benefits of investment in new energy sources and energy-efficient technology. Some estimates suggest that the transition to energy efficiency could result in a net gain rather than a net loss to the global economy.
But Lomborg’s more important mistake is to assume that we can attach a single, meaningful figure to the costs incurred by global warming. If there is one thing we know about climate change, it’s that it is a non-linear process, whose likely impacts simply cannot be totted up like the expenses for a works outing to the seaside. Even those outcomes we can predict are almost impossible to cost. We now know, for example, that the Himalayan glaciers which feed the Ganges, the Bramaputra, the Mekong, the Yangtze and the other great Asian rivers are likely to disappear within 30 or 40 years. If these rivers dry up during the irrigation season, then the rice production which currently feeds over one third of humanity ceases to be viable, and the world goes into net food deficit. If Lomborg believes he can put a price on that, he has plainly spent too much of his life with his calculator, and not enough with human beings.
Reading Lomborg’s work, it is hard to reach any conclusion other than that he is telling the powerful what they want to hear, irrespective of the real costs to everyone else.