The faint young Sun problem

  title={The faint young Sun problem},
  author={Georg Feulner},
  journal={Reviews of Geophysics},
  • G. Feulner
  • Published 19 April 2012
  • Geology
  • Reviews of Geophysics
For more than four decades, scientists have been trying to find an answer to one of the most fundamental questions in paleoclimatology, the “faint young Sun problem.” For the early Earth, models of stellar evolution predict a solar energy input to the climate system that is about 25% lower than today. This would result in a completely frozen world over the first 2 billion years in the history of our planet if all other parameters controlling Earth's climate had been the same. Yet there is ample… 
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