How do we know that recent climate change is attributable to human activities rather than natural causes?
The present atmospheric concentration of carbon dioxide has not been exceeded for the past 650,000 years, and possibly not for 20 million years. Ice core records show that carbon dioxide levels in the atmosphere varied between 180 and 280 parts per million (ppm) due to glacial cycles. For the past 10,000 years global atmospheric carbon dioxide has been quite stable at between 260 and 280 ppm, and level at about 280 ppm from 1000 to 250 years ago.
Related Questions
- How do we know that most recent global warming is attributable to human activities rather than natural causes?
- How do we know that recent climate change is attributable to human activities rather than natural causes?
- How do we know that most global warming is attributable to human activities rather than natural causes?
