1. WORKSHOP: LESSONS FROM THE 2007 ICE MINIMUM
Understanding: Sea ice prediction
Near-term
Seasonal forecast, e.g. summer 2008
Summer 2009 …
Long-term
Decadal
Mid-century

2. WORKSHOP: LESSONS FROM THE 2007 ICE MINIMUM
Winter sea-ice extent (3/2008) highest in last 4 years
Johannessen, Env. Res. Lett. (submitted)

3. WORKSHOP: LESSONS FROM THE 2007 ICE MINIMUM
Drobot et al., Science (submitted); Maslanik et al., GRL (2007)

4. WORKSHOP: LESSONS FROM THE 2007 ICE MINIMUM
Based on ice age patterns, ice cover is preconditioned for another ice retreat  2007
Probability of new record minimum in 2008: 64% to 84%
Drobot et al., Science (submitted); Maslanik et al., GRL (2007)

5. WORKSHOP: LESSONS FROM THE 2007 ICE MINIMUM

6. WORKSHOP: LESSONS FROM THE 2007 ICE MINIMUM
Annual sea-ice extent 1900–2007 (observed – green, and IPCC modeled mean ensemble – black) and predictions for 2007–2050 under projected CO2 scenarios of the IPCC.
Johannessen, Env. Res. Lett. (submitted)

7. WORKSHOP: LESSONS FROM THE 2007 ICE MINIMUM
Annual sea-ice extent is inversely, linearly proportional to CO2
Unless 2007 is an anomaly and not the beginning of a rapid end, then this statisticla model is not on target.. Moreover, no feedbacks, possibly non-linear
Johannessen, Env. Res. Lett. (submitted)

8. WORKSHOP: LESSONS FROM THE 2007 ICE MINIMUM
Understanding: Sea ice prediction
Has the ‘tipping’ point already been passed?
Considerations:
Accelerators
Decelerators
Reversal mechanisms