Quantitative evaluation of regional precipitation forecasts using multi-dimensional remote sensing...
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Transcript of Quantitative evaluation of regional precipitation forecasts using multi-dimensional remote sensing...
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)