Presentation is loading. Please wait.

Presentation is loading. Please wait.

WMO International Cloud Modeling Workshop, 12-16 July 2004 A two-moment microphysical scheme for mesoscale and microscale cloud resolving models Axel Seifert.

Similar presentations


Presentation on theme: "WMO International Cloud Modeling Workshop, 12-16 July 2004 A two-moment microphysical scheme for mesoscale and microscale cloud resolving models Axel Seifert."— Presentation transcript:

1 WMO International Cloud Modeling Workshop, July 2004 A two-moment microphysical scheme for mesoscale and microscale cloud resolving models Axel Seifert National Center for Atmospheric Research

2 WMO International Cloud Modeling Workshop, July 2004 Motivation Aerosol-Cloud interactions can be a strong feedback in the climate system Quantitative precipitation forecasts suffer from oversimplified microphysical models Many ongoing projects on weather modification, but little scientific knowledge  improved microphysical models are necessary

3 WMO International Cloud Modeling Workshop, July 2004 Microphysical models: x = particle mass

4 WMO International Cloud Modeling Workshop, July 2004 Generalized Gamma Distribution x = particle mass, = shape parameter,  = tail parameter D in  m

5 WMO International Cloud Modeling Workshop, July 2004 Use mass and number concentrations to get an explicit size information  4 Variables A two-moment warm phase scheme (Seifert and Beheng 2001, Atmos. Res.)

6 WMO International Cloud Modeling Workshop, July 2004 A two-moment mixed-phase cloud scheme

7 WMO International Cloud Modeling Workshop, July 2004 A two-moment mixed-phase cloud scheme

8 WMO International Cloud Modeling Workshop, July 2004 What happend so far.... Comparison with bin microphysics Sensitivity study showed that especially high CAPE, low wind shear convective systems are sensitive to aerosols/CCN Simulation of isolated observed thunderstorms Severe storms during BAMEX WRF, MM5 and LM implementation

9 WMO International Cloud Modeling Workshop, July 2004 Comparison within HUCM

10 WMO International Cloud Modeling Workshop, July 2004 Comparison within HUCM

11 WMO International Cloud Modeling Workshop, July 2004 BIN BULK CONT MARI Timeseries of maximum mass concentrations

12 WMO International Cloud Modeling Workshop, July 2004 Total grid averaged precipitation

13 WMO International Cloud Modeling Workshop, July 2004 CCN effects on different storm types Weisman and Klemp (1982) sensitivity study, but now including CCN as a third external parameter: Variation of 1. CAPE 2. vertical wind shear 3. CCN concentration Effects on total precipitation? (Seifert and Beheng 2003, submitted)

14 WMO International Cloud Modeling Workshop, July 2004 Total 3h-precipitation supercell convection multicell conv.

15 WMO International Cloud Modeling Workshop, July 2004 Total 3h-precipitation and rel. change for cont. CCN

16 WMO International Cloud Modeling Workshop, July 2004 WRF simulation of a CRYSTAL-FACE storm (100x80 km, 250 m resolution, warm bubble, single sounding)

17 WMO International Cloud Modeling Workshop, July 2004 Observations vs. WRF simulation X-band reflectivity

18 WMO International Cloud Modeling Workshop, July 2004 Observations vs. WRF simulation W-band reflectivity

19 WMO International Cloud Modeling Workshop, July 2004 Attenuation by liquid water

20 WMO International Cloud Modeling Workshop, July 2004 Composite NEXRAD Radar 4 km BAMEX forecast 36 h Reflectivity 4 km BAMEX forecast 12 h Reflectivity Valid 6/10/03 12Z Real-time WRF 4 km BAMEX Forecast

21 WMO International Cloud Modeling Workshop, July 2004 BAMEX 10 June 00 UTC + 09h WRF’s Lin-type scheme Reisner-Thompson scheme Seifert-Beheng scheme Column max. reflectivity (WRF)

22 WMO International Cloud Modeling Workshop, July 2004 BAMEX 10 June 00 UTC + 23h WRF’s Lin-type scheme Reisner-Thompson scheme Seifert-Beheng scheme Column max. reflectivity (WRF)

23 WMO International Cloud Modeling Workshop, July 2004 BAMEX 10 June 00 UTC + 23h WRF’s Lin-type scheme Reisner-Thompson scheme Seifert-Beheng scheme Accumulated precip during 23 h

24 WMO International Cloud Modeling Workshop, July 2004 Acknowledgements: Klaus D. Beheng, Karlsruhe Uli Blahak, Karlsruhe Michael Baldauf, Karlsruhe Jochen Förstner, Karlsruhe Alexander Khain, Jerusalem Andrei Pokrovsky, Jerusalem Bill Hall, NCAR Andy Heymsfield, NCAR Morris Weisman, NCAR Gerry Heymsfield, NASA Scientific Computing Centers at Karlsruhe and NCAR

25 WMO International Cloud Modeling Workshop, July 2004

26

27 Various one- and two-moment schemes

28 WMO International Cloud Modeling Workshop, July 2004 BAMEX 10 June 00 UTC + 19h WRF’s Lin-type scheme Reisner-Thompson scheme Seifert-Beheng scheme Column max. reflectivity (WRF)

29 WMO International Cloud Modeling Workshop, July 2004 Maximum vertical velocities (HUCM)

30 WMO International Cloud Modeling Workshop, July 2004 Coupling of microphysics and dynamics!


Download ppt "WMO International Cloud Modeling Workshop, 12-16 July 2004 A two-moment microphysical scheme for mesoscale and microscale cloud resolving models Axel Seifert."

Similar presentations


Ads by Google