A report prepared by the London School of Economics says for every $6.63 spent on contraceptives over the next 40 years it would cost $31.48 to achieve the same reduction in CO2 emissions with low carbon technology, the Daily Telegraph reported Wednesday.
"It's always been obvious that total emissions depend on the number of emitters as well as their individual emissions," says Roger Martin, chairman of the Optimum Population Trust at the London School of Economics.
Martin says carbon tonnage can't decrease while the population is increasing.
United Nations data indicates that family planning could reduce unintended births by 72 percent, trimming the world's population by half a billion to 8.64 million in 2050.
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