From National Geographic:
A NEW SCIENTIFIC analysis of millions of possible climate futures found only a narrow window to keeping global warming to levels the international community has deemed safe.
Out of 5.2 million possible climate futures, carbon emissions must reach zero by 2030 in every country in the world if we are to stay at less than 3.6 degrees Fahrenheit (2 degrees Celsius) by 2100 of warming, the target set by the United Nations to avoid the worst impacts of climate change, from rising seas to deadly heat waves.
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