1. Uncertainty Is Knowlege The Case of Climate Change Peter Guttorp Statistics

3. Outline 1. IPCC 2. History of climate change 3. Measuring temperature 4. Temperature trends 5. Comparing models to data 6. Ranking the hottest years 7. Feedback loops 8. Sea level rise 9. Extremes 10. Visualization

4. Class structure I talk for a while Discussion in groups Class discussion Material to look at in advance available on the class web site To get credit, must hand in two brief summaries of the class discussions Slides will be online after the class meeting

5. Science is uncertain If a scientific theory can predict things that later turns out to happen, and explain why they happened it is a successful theory and we act as if it is true. Later the theory may be found not quite right, and we may have to modify our behavior. Good science can say how uncertain it is.

6. Intergovernmental Panel on Climate Change UNEP/WMO Produces assessment reports about every 5 years Governments, science groups nominate chapter editors Chapter editors pick authors Anyone can review the report

7. Describing uncertainty How sure are we Exceptionally unlikely to Virtually certain How well do we agree Low, medium or high How much evidence is there Low, medium or high

8. A summary of the summary Hans Rosling

9. Issues to discuss Find three things that are uncertain in Rosling’s presentation Can we eliminate (or at least reduce) each of these uncertainties?