1. Precipitation in Norway Idar Barstad Idar.Barstad@uni.no Uni Research – (UniComputing / Bjerknes Centre for Climate Research)@uni.no

2. Motivation: Orographic precipitation and climate change Results from a small-scaled field campaign

3. Nesttun, 14th September 2005

4. Return period /-amount for Bergen (daily data) x 2 months later 1000 100 1 Return value (mm/day) Return period (years)

5. 14th Nov 2005 NERSC/NASA

6. Pressure patterns leading up to extreme precipitation -2 days Cluster # 2 3 Extreme day (Barstad and Sorteberg, 2012, in prep.)

7. Mean precipitation Norway – whole year Sorteberg & Kvamstø, 2008 ARPEGE (HADCM3) ARPEGE (GFDL)

8. The study Increasing demand of products from numerical models of high resolution Q: Can models deliver what we ask for?

9. Experimental set-up Collect precipitation using rain gauges (“tipping” buckets) For 12 weeks 2006 across an island at the west coast of Norway Run numerical model - WRFV3.3, 9-3-1 km, MYJ, Thompson MP - spectral nudging (>1000km), 45-15-5 sec time step Material from a submitted paper (Barstad, 2012 ; QJRMS)

10. Domain 9-3-1 km domain ~500 m peaks 10 km Contours every 50 m

11. Total precip 3 km frontal 3 km convective Vertically int. water vapor rose

12. Total precip at 1-km grid

13. 1 108 18 9 2 mod/obs

14. Precip at high percentiles OBS mod (10min accumulation)

15. Time-step prec OBS 1 km3 km (0.2 mm per tip)

16. Radiosonde info

17. Shallow convection

18. Extreme precip cases (q99)

19. Time-step prec OBS 1 km3 km

20. WRF and shallow convection C Vincent (2010)

21. Zoom in on the convection It doesn’t seem to be as well defined and organized as suggested by the model

22. Thank you! Email: Idar.Barstad@uni.no

23. Extreme precipitation – w Norway Caroletti and Barstad (2009) A1B scenario – downscaling using 12 GCM models