Researchers have long wondered why water on Earth was not frozen during the early days of the planet, when the sun emanated only 70 to 75 percent as much energy as it does today. Some theorize that high levels of greenhouse gases in the atmosphere, the same mechanism cited in global warming today, were key. But new research involving Stanford scientists has a different explanation: The oceans, much larger than today, absorbed enough heat from the sun to avoid turning into ice.
Stanford University Channel on YouTube:
Tagged under: earth science,climate change,temperature,greenhouse gas
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