摘要：Anthropogenic carbon dioxide
(CO2) emissions are projected to impose economic costs due to the associated
climate change impacts. Climate change impacts can be reduced by abating
CO2 emissions. What would be an economically optimal investment in abating
CO2 emissions? Economic models typically suggest that reducing
CO2 emissions by roughly ten to twenty per cent relative to business-as-usual
would be an economically optimal strategy. The currently implemented
CO2 abatement of a few per cent falls short of this benchmark. Hence, the global community
may be procrastinating in implementing an economically optimal strategy. Here we use a simple economic model to estimate the regrets of this procrastination—the
economic costs due to the suboptimal strategy choice. The regrets of procrastination can
range from billions to trillions of US dollars. The regrets increase with increasing
procrastination period and with decreasing limits on global mean temperature increase.
Extended procrastination may close the window of opportunity to avoid crossing
temperature limits interpreted by some as 'dangerous anthropogenic interference with the
climate system' in the sense of Article 2 of the United Nations Framework Convention on
Global Climate Change.
