Quantitative evaluation of regional precipitation

forecasts using multi-dimensional remote sensing

observations (QUEST)

Nicole van Lipziga, Susanne Crewella, Felix Amente, George Craigb, Jürgen Fischerc, Martin Hagenb, Monika Pfeiferb, Marc Schröderc,

Wenchieh Yena

a Meteorologisches Institut, Universität Münchenb DLR-Institut für Physik der Atmosphäre, Oberpfaffenhofen

c Institut für Weltraumwissenschaften, Freie Universität Berlind Deutscher Wetterdienst, Offenbach

e Meteorologisches Institut, Universität Bonn

GOAL: Evaluation of the clouds

and precipitation in LMK

• Satellite observations (Free University Berlin; poster by Marc Schröder)

• Weather radar (Deutscher Wetterdienst; poster by Wenchieh Yen)

• Polarimetric Radar (DLR institute of atmospheric physics; poster by

Monika Pfeifer)

• In-situ rain gauge data (Deutscher Wetterdienst and federal and local

water authorities)

• Ground-based remote sensing (microwave radiometer, cloud radar,

Micro Rain Radar, Wind profilers, Lidar)

• Atmospheric Observatories (Lindenberg, Cabauw)

• Data from General Observing Period (Poster by Susanne Crewell)

MSG, true colour images from 12 August 2004

08:00 09:00 10:00 11:00 UTC

08:00 09:00 10:00 11:00 UTC

• Spatial coverage

• Temporal resolution

(MSG: 15 min.)

Satellite observationsFree University Berlin; poster by Marc Schröder

Lokal Model, cloud cover

MSG

LMK

MODIS

MERISMSG, 12.08.04

MODIS, cloud coverLM

Pixelsize of satellites and LMIWV

cloud optical thickness

• Spatial resolution (up to 250m); subgrid scale variability

• Several products of validated atmospheric and cloud properties

• Automated data archiving (20 Gb / day)

• Near real time processing

• Sensor synergy

Satellite observations

Weather radarDeutscher Wetterdienst; poster by Wenchieh Yen

• Detailed information on timing and location of precipitation events

• Spatial resolution: 1 km

• Temporal resolution: 5 minutes

• Quantitative determination of precipitation is prone to several errors

PI product: International precipitation composite

Near-ground reflectivity in 6 classes

360x360 pixels, Spatial resolution: 4km

Temporal resolution: 15 minutes

Precipitation can be derived from reflectivity using Z=a·Rb

• Different polarimetric variables (Reflectivity, LDR, ZDR) give information on phase, shape, density, falling behavior of the hydrometeors

• Insights in Microphysics of Convective Systems

• Classification of Hydrometeors

• Better Quantitative Rain Estimates

• Spatial resolution: about 300m

• Temporal resolution: about 15 min

Polarimetric RadarDLR institute of atmospheric physics; poster by Monika Pfeifer

SynPolRad

Concept of a forward operator

Polarimetric Radar

Model output

Nature

Strategy for LM evaluation within QUEST: Evaluation of long time

period (months) is needed to identify systematic biases

Integrated water vapor

Frequency of precipitation

Liquid water path*

* Lokal-Modell: grid scale LWP + subgrid scale contribution according to radiation scheme

August 2001 September 2001

(E. van Meijgaard, KNMI)

Cabauw site, daily means

Strategy for LM evaluation within QUEST

• Shallow convection casesWMO cloud modeling workshop Hamburg July 2004. Case I: Shallow convection case based on BBC (BALTEX Bridge Campaign) Cabauw observations

• 23 September 2001 • 21 May 2003

• Precipitation cases • 19 September 2001: frontal precipitation in the Netherlands • 8 July 2004: strong precipitation over Germany • 12 August 2004: strong thunderstorm over Germany

• Long-term evaluation• Summer 2004 or 2005• General Observing Period 2007

Kic

k-off Q

PF

cas

es

Shallow convection casesWMO cloud modeling workshop Hamburg July 2004. Case I: Shallow convection case based on BBC (BALTEX Bridge Campaign) Cabauw observations

• 23 September 2001 • 21 May 2003

Lipzig et al., 2005. The representation of low-level clouds in atmospheric models: Part I: Temporal evolution from ground-based remote sensing during the BALTEX Bridge Campaigns. Submitted to Atmospheric Research

Schröder et al, 2005. The representation of low-level clouds in atmospheric models: Part II: Spatial distribution from satellite remote sensing during the BALTEX Bridge Campaigns. Submitted to Atmospheric Research.

- 440kmx440km- dx=2.8km- dt=25s- spin-up=12 hrs- length of integation=36 hrs- sst prescribed-- lateral boundaries: analyses from LM (7km) of the Deutscher Wetterdienst (DWD)

Version 3.9: ice and rain included as prognostic variables

Convective cloud scheme switched off

Felix Ament

1. Lokal Modell domain for shallow convection (WMO) cases

Crewell et al, 2005

BALTEX BRIDGE Campaign (BBC)

Meteorological tower

Satellite remote sensingradarRegional network

Ground based remote sensing Aircraft

Comparison with Integrated Profiling Technique

Main conclusion: LM underestimates the lifetime of clouds but overestimate the liquid water content

2. Lokal Modell domain for precipitation cases

• 19 September 2001: frontal precipitation in the Netherlands • 8 July 2004: strong precipitation over Germany • 12 August 2004: strong thunderstorm over Germany

Identical to WMO-settingsexcept for model domain900km x 1100km

Synoptic situation on 12 Aug 2004

ECMWF Mean sea level pressure

12UTC 18UTC

6UTC0UTC

Synoptic situation on 12 Aug 2004

MODIS overpass 10:55UTC

Cloud cover

Cloud optical thickness

Marc Schröder

Cloud cover 12 Aug 2004 0:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 1:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 2:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 3:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 4:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 5:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 6:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 7:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 8:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 9:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 10:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 11:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 12:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 13:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 14:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 15:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 16:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 17:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 18:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 19:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 20:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 21:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 22:00 UTC

MSG LM

Marc Schröder

Cloud cover 12 Aug 2004 23:00 UTC

MSG LM

Marc Schröder

Quantitative measures to identify

biases in cloud forecasts

For more: Poster Marc Schröder

12 Aug 2004 hourly MSG/LM fields

12 Aug 2004

DWD radar international composite

LM

Wenchieh Yen

DWD radar / LM at 18:00 UTC

München

Wenchieh Yen

DWD radar / LM at 21:00 UTC

München

Wenchieh Yen

Polarimetric radar 12 Aug 2004

Martin Hagen

Monika Pfeifer

Poldirad (PPI: 1 deg) 17:01 UTC

SynPolRad (30m) 21:00 UTC

Monika Pfeifer

Poldirad (RHI) 17:01 UTC

SynPolRad 21:00 UTC

LMBrightband strongest signalZ up to 60 dBZ in the brightband

PoldiradTwo cores related to graupel and hailZ up to 60 dBZ throughout cell

Another example (see poster Monika Pfeifer): 9 July 2002

Polarimetric radar foreward operator

Summary

•BALTEX Bridge Campaign cases have been used to evaluate shallow

cloud conditions in LM

• Integrations for precipitation cases have been performed

• Quantitative measures for evaluation using satellite observations are

under development

• Integrations with graupel scheme will be performed for evaluation using

Polarimetric radar

Posters will be on the QUEST web site:

Marc Schröder: Satellite observations

Wenchieh Yen: DWD Weather radar

Monika Pfeifer: Polarimetric Radar

Susanne Crewell: General Observing Period 2007 (GOP)