• Current climate models are not reliable enough
  • climate dynamics are insufficiently understood
  • values for climate model parameters are too uncertain
    • The uncertainty does not change the key predictions
  • long-term climate predictions are impossible
    • we can't even predict short-term weather very well
      • Weather and climate prediction are not the same
    • It's impossible to predict chaotic systems
      • long-term trends are predictable
  • Scientists adjust models to avoid producing outlying results
• Current climate models are sufficiently reliable
  • They have been refined over a long period
  • They are highly sophisticated
  • They have been backtested with historical data
  • They are based on well-validated models