precipitation in norway idar barstad uni research – (unicomputing / bjerknes centre for climate

Precipitation in Norway

Idar BarstadIdar.Barstad@uni.no

Uni Research – (UniComputing / Bjerknes Centre for Climate Research)

Motivation: Orographic precipitation and climate change

Results from a small-scaled field campaign

Nesttun, 14th September 2005

Return period /-amount for Bergen (daily data)

x

2 months later

10001001

Ret

urn

valu

e (m

m/d

ay)

Return period (years)

14th Nov 2005

Pressure patterns leading up to extreme precipitation

-2 days

-2 days

Cluster #

2

3

Extreme day

Extreme day

(Barstad and Sorteberg, 2012, in prep.)

Mean precipitation Norway – whole year

Sorteberg & Kvamstø, 2008

ARPEGE (HADCM3)ARPEGE (GFDL)

The studyIncreasing demand of products from numerical models of high resolution

Q: Can models deliver what we ask for?

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)

Domain9-3-1 km domain

~500 m peaks

10 kmContours every 50 m

Total precip3 km frontal 3 km convective

Vertically int.water vaporrose

Total precip at 1-km grid

1

10 8 18 92

mod/obs

Precip at high percentiles

OBS

mod

(10min accumulation)

Time-step precOBS

1 km 3 km

(0.2 mm per tip)

Radiosonde info

Shallow convection

Extreme precip cases (q99)

Time-step precOBS

1 km 3 km

WRF and shallow convection

C Vincent (2010)

Zoom in on the convectionIt doesn’t seem to be aswell defined and organizedas suggested by the model

Thank you!

Email: Idar.Barstad@uni.no

Extreme precipitation – w Norway

Caroletti and Barstad (2009)

A1B scenario – downscalingusing 12 GCM models