SUBJECT AND CENTRAL QUESTION
How Do We Know Humans Are Responsible? This is the week for carbon isotopes, declining atmospheric oxygen, fossil-carbon bookkeeping, tropospheric warming/stratospheric cooling and attribution models.
RECOMMENDED VIEWING
Richard Alley/PBS, “Earth: The Operators' Manual,” 53:42. It specifically walks through the evidence that the modern CO₂ increase comes from fossil fuels rather than volcanoes or another natural source.Earth: The Operators' Manual
CLASS DISCUSSION
What observation would have to be different for the human-causation hypothesis to fail? This turns the discussion into falsifiable science rather than opinion.
