The costs of reducing climate-changing greenhouse emissions to safe levels may not be as great over the long term as some have predicted, according to the findings of a new study.
The scientific consensus is that global warming should be limited to 2 degrees Celsius above pre-Industrial levels to prevent dangerous climate change. To achieve this, it’s estimated that greenhouse gas emissions worldwide need to be cut by 60 to 80 per cent by 2050 to ensure overall atmospheric concentrations are stabilised at 450-550 parts per million of
CO2 equivalent.
It has been thought costs rise exponentially the tougher the emissions reduction and concentration level goals are. The study findings suggest that this is not the case.
A paper lead-authored by Michiel Schaeffer of the Netherlands’ Wageningen University, and published in the journal Proceedings of the National Academy of Science, finds that large investments in cutting emissions early on will deliver results in the long run and that these high early costs won’t blow out in the later years.
The study estimates that for an annual cost of 2 per cent of world GDP, there is a 90 per cent chance that the +2 degrees target can be met.
By contrast, any modest initial investments will be largely “hardly effective”; doing “a bit will get you nowhere”, Schaeffer said. Spending 0.5 per cent of GDP would give just a 10 per cent chance of achieving that temperature target while an investment of 1 per cent of GDP offers only a 40 per cent chance.
“Our work suggests that spending larger amounts of money to control
carbon dioxide levels or temperatures skewed by climate change may
prove worthwhile to a government or a corporation,” Schaeffer said.
Reuters 22/12/08, livemint.com, Wall Street Journal 23/12/08