Climate change may be far worse than scientists thought, causing global temperatures to rise by at least 4 degrees Celsius by 2100, or about 7.2 degrees Fahrenheit, according to a new study.

The study, published in the journal Nature, takes a fresh look at clouds' effect on the planet, according to a report by The Guardian. The research found that as the planet heats, fewer sunlight-reflecting clouds form, causing temperatures to rise further in an upward spiral.

That number is double what many governments agree is the threshold for dangerous warming. Aside from dramatic environmental shifts like melting sea ice, many of the ills of the modern world -- starvation, poverty, war and disease -- are likely to get worse as the planet warms.

"4C would likely be catastrophic rather than simply dangerous," lead researcher Steven Sherwood told the Guardian. "For example, it would make life difficult, if not impossible, in much of the tropics, and would guarantee the eventual melting of the Greenland ice sheet and some of the Antarctic ice sheet."
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