COST 722 : Short Range Fog Forecasting, Visibility and low cloud6th EMS Conference Ljubljana, September 2006

COST-722

Comparison of 3D fog models and satellite

fog/ very low stratus products

M.Masbou1,2, M. D. Müller3 & Jan Cermak4

1 Meteorological Institute, University of Bonn, Germany, mmasbou@uni-bonn.de

2 Laboratoire de Météorologie physique, University Blaise Pascal, Clermont-Ferrand, France

3 Institute of Meteorology, Climatology & Remote Sensing, University of Basel, Switzerland

4 Laboratory for Climatology & Remote Sensing, University of Marburg, Germany

Transport Safety and Fog Events

Three-dimensional Fog forecast model

Simulation on the same Lindenberg Area (Germany N 53,21 W 14,11)

Based on NMM non-hydrostatic Model (Janjic Z. I., 2003)

Based on “Lokal Modell” (LM) non-hydrostatic Model (Steppeler J. & al., 2003)

Hz. Resolution: 1 x 1 km Area: 160 x 160 km

Hz. Resolution: 2.8 x 2.8 km Area: 280 x 280 km

Vert. Resolution: 45 Levels concentrated nearest the ground

Vert. Resolution: 40 Levels Δzmin=4m at the ground

Same Fog Microphysics Parameterization PAFOG (Bott & Trautmann 2002)

NMM-PAFOG

LM-PAFOG

Initialization and Boundary: NMM 13 km

Initialization and Boundary: LME Model 7km available for all Europe

MSG SEVIRI Satellite Products

1- Fog is a cloud

2- in water phase

3- composed of small droplets

4- low above the ground and

5- stratiform

Satellite Products

Pc- Cloud Confidence Level

Threshold

Cloud Confidence Rangeis set to 5 K

Confidence Level

If 0.5

1.0Cloudy

Clear 0.0

Blackbody temperature difference

Interpolation of satellite datato high resolution model grid

Compute contingency tablebased on pixel values.

Confidence value thresholdof 45 % for fog discrimination

Comparison 3D Models – Satellite Products : How to procede ?

September, 27th 2005

01 UTC NOAA17

+

+

LM-PAFOG

Δx=2.8km

280x280 km

NMM-PAFOG

Δx= 1 km

160x160 km

Lindenberg Area – September 2005, 27th 00UTC

LM-PAFOG

Δx= 2.8km

280x280 km

NMM-PAFOG

Δx= 1 km

160x160 km

Lindenberg Area – September 2005, 27th 01UTC

LM-PAFOG

Δx= 2.8km

280x280 km

NMM-PAFOG

Δx= 1 km

160x160 km

Lindenberg Area – September 2005, 27th 02UTC

Lindenberg Area – September 2005, 27th 03UTC

LM-PAFOG

Δx= 2.8km

280x280 km

NMM-PAFOG

Δx= 1 km

160x160 km

Lindenberg Area – September 2005, 27th 04UTC

LM-PAFOG

Δx= 2.8km

280x280 km

NMM-PAFOG

Δx= 1 km

160x160 km

Lindenberg Area – September 2005, 27th 05UTC

LM-PAFOG

Δx= 2.8km

280x280 km

NMM-PAFOG

Δx= 1 km

160x160 km

Lindenberg Area – September 2005, 27th 06UTC

LM-PAFOG

Δx= 2.8km

280x280 km

NMM-PAFOG

Δx= 1 km

160x160 km

LWC 2m

Integrated LWC 0-2000m

LM-PAFOG: Forecast hour 10 UTC – DECEMBER 2005

LWC 2m

Integrated LWC 0-2000m

NMM-PAFOG: Forecast hour 38 UTC – DECEMBER 2005

INTEGRATED LWC 0-2 000m: Larger Statistic

LM-PAFOG

NMM-PAFOGLM-PAFOG

Accordance between Satellite Products and 3D Models

Further Developments are necesserary

BUT, Both Model have RELATIVELY LOW discrimination capabilities

870mLindenberg

NOAA/AVHRR

Verification with NOAA data - 10 October 2005NMM_PAFOG

Test on Zurich Area

Verification with Meteosat 8 data - 11 October 2005

Zürich airport Zürich airport

90 km

Zürich airport

Verification with Meteosat 8 data - 11 October 2005

Zürich airport

CONCLUSIONO

utl

oo

k

- Integrated Column water 0-2000m COMPARABLE

- Long time verification on Zurich Area

- Modelled 2m LWC not directly comparable to currently available satellite products (Low stratus Products)

- Comparison Satellite fog mask/3D fog Models

- Zurich results from COMPLEX TOPOGRAPHY show BETTER performance.

COST 722

Th

anks