The Anthropogenic Greenhouse Era Began Thousands of Years Ago

  title={The Anthropogenic Greenhouse Era Began Thousands of Years Ago},
  author={William F. Ruddiman},
  journal={Climatic Change},
The anthropogenic era is generally thought to have begun 150 to 200 years ago, when the industrial revolution began producing CO2 andCH4 at rates sufficient to alter their compositions in the atmosphere. A different hypothesis is posed here: anthropogenic emissions of these gases first altered atmospheric concentrations thousands of years ago. This hypothesis is based on three arguments. (1) Cyclic variations in CO2 andCH4 driven by Earth-orbital changes during the last 350,000 years predict… Expand
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Commentary on “The Anthropogenic Greenhouse Era Began Thousands of Years Ago”
Bill Ruddiman (Climatic Change, 61, 261–293, 2003) recently suggested that early civilisations could have saved us from an ice age because land management over substantial areas caused an increase inExpand
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