This is Scientific American 60-Second Earth. I'm David Biello. Your minute begins now.
Despite the Great Recession, more people are better off around the world today than ever before.
At the same time, atmospheric carbon dioxide levels have never been higher in human history, thanks to fossil fuel burning, forest clearing and other activities that make people rich.
So what can be expected if the world increases the wellbeing of an ever increasing proportion of people?
In short: even more CO2.
That's the finding of a study in the journal Nature Climate Change.
Economists and policy analysts held out hope that global wealth could continue to rise without also raising CO2 emissions.
But a look back at life expectancy at birth compared with per capita pollution around the world from 1970 to 2009 suggests otherwise.
Economic development in the poorest countries starts off by reducing CO2 pollution in the 1970s and 1980s,
perhaps because fossil fuel burning replaces even more polluting fires in individual homes.
But in more recent years that benefit has leveled off.
And developed countries like the U.S.or China seem to increase emissions whenever the economy grows.
A switch to energy sources that produce less CO2 seems key to breaking that link.
In the long run, after all, checking climate change is vital to human wellbeing too.
Your minute is up, for Scientific American 60-Second Earth. I'm David Biello.
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