With Speed and Violence Fred Pearce - Global Commons Institute

which was promptly exceeded by an estimated $70 billion for 2005. Total
economic losses for 2005, including uninsured losses, are expected to be
three times higher: cleaning up after Hurricane Katrina alone may
eventually cost $ 100 billion. Incidentally, a simple extrapolation of trends
in insurance claims stemming from extreme weather in recent years
suggests that they will exceed total global economic activity by 2060. That
may be slightly wacky math, but it is sobering nonetheless.
Not surprisingly, economists disagree about the cost of inaction on
climate change as much as they do about the cost of action. Some have
attempted to assess the "social cost" of every ton of carbon put into the air.
One recent review found a range from approaching $1,700 per ton down to
zero. The British government, which commissioned the review, settled on a
figure of $70 per ton. One reason for the wide range is accounting practices.
Economists routinely apply a discount to the cost of anything that has to be
paid for in the future. Dealing with climate change that may happen decades
or even centuries ahead allows for huge discounts. Some economists say that
very long-term impacts—such as the rise of sea levels as ice caps
melt—should be discounted to zero.
This discounting of the future may be a convenient device for corporations,
or even governments in their day-to-day business. But it is less clear how
sensible it is for the management of a planet. If corporate finances or a
nation's economy go wrong, shareholders can sell their shares and
governments can print money or go cap in hand to the International
Monetary Fund. But the planet, our only planet, is rather different.
Moreover, the existing estimates of social cost are based on IPCC studies
that so far have not included many of the irreversible positive feedbacks to