current and future use of satellite data in nwp at environment canada satellite direct readout...
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Current and Future Use of Satellite Data in NWP at Environment Canada
Satellite Direct Readout Conference 2011Miami, USADavid Bradley, Gilles Verner, Mike ManoreMeteorological Service of CanadaApril 4-8, 2011
Context
Environment Canada (EC)Meteorological Services of Canada (MSC)
“providing weather and environmental predictions and services to reduce risks and contribute to the well-being of Canadians”
– Operations (e.g. 24-7 forecasts and warnings, NWP operations)– Monitoring Networks (e.g. Upper Air, Surface, Climate, Water, Space-based)– Environmental Predictions and Services (e.g. Ice, Aviation, Military, Policy)– Science (e.g. Air Quality, Climate, Meteorological)
Canadian Meteorological Centre (CMC)
Meteorological Research Division: Data Assimilation, Modeling, Cloud Physics
CMC Development Division: Data Assimilation, Numerical Weather Prediction, Weather Elements, Scientific Applications
IT Infrastructure (CIOB): Supercomputer,National Telecommunications, Network,User support
CMC Operations: Analysis & Prognosis, Env. Emergency Response (VAAC), Air Quality, Implementation and Operational Services
Role of CMC and Regions in Weather Prediction
NAVCANADA
Dept. NationalDefence
Public
Marine
Agriculture
Private sector...
CMC
Supercomputer/TelecomDecoding, QC & Databasing
Data Assimilation & ModelingPost-processing
5 EC Regions
WarningsForecastsDisseminationServicesData + Prod.
CanadianIceService
Aviation& DefenseServices
USERSCanadian Data
International Data(GTS Washington, NESDIS, Eumetsat,UKMet, etc.)
Research in NWP,Data Assimilation,Remote Sensing
and AQ
MRD
Tech. transfer
DATA ACQUISITION
COMPUTER ANALYSIS OF DATA
COMPUTER FORECAST
INTERPRETATION &DISSEMINATION
• Observations obtained from weather balloons, surface stations, ships, satellites, aircrafts, drifting buoys.
• Produce Values of atmospheric variables (temperature, winds, humidity & pressure) at mesh points.
• Run computer model of atmosphere. Provides forecast values of atmospheric variables at mesh points.
• Applications. Forecasts interpreted in terms of weather elements (e.g. sunny and cloudy periods), disseminated via media.
THE MAKING OF A WEATHER FORECAST
Data Assimilation Process
First Guess(6hr fcst)
Analysis(Spatial QC)
NWP model
Error Statistics(Observation and Forecast)
Data Acquisition
Data Quality Control
grilleptN prev
i
Nobs obs
ii Err
xP
Err
xOxJ
22 )()()(
Cost
MIN J(x) xa
J(xi-1) Use to find xi
Unified Numerical Forecasting System
Global Environmental Multiscale (GEM) Forecasting & Modelling System
2010-2020
Regional and Mesoscale Forecast ( 24-48 h, 10-15 km )
& Data assimilation
Medium-range Forecast ( 240 h, 10 to 35 km )
& Data assimilation
Middle Atmosphere Model &
Data assimilation
Regional Climate Model
Monthly Forecast
Multi- Seasonal Forecast
Ensemble Forecast
Limited-Area Model 0-24h 1-2.5km
& Data assimilation
S P A C E
S C A L E
TIME SCALE
Micro-meteorology (10m-1km)
Main Uses of Observational Data at CMC CMC is a major user of observational data, both Canadian
and foreign, main uses are:
• Data Assimilation: Blending of observations with other information to generate initial conditions (the analysis) to run the NWP forecast models. Radiosonde andRadiosonde and Satellite data are of crucial importanceSatellite data are of crucial importance.
• Forecast Verification: Observations (upper air, surface, satellite) considered as truth (after QC), and used to verify the accuracy of forecasts (both model and Scribe) and perform diagnostic studies.
• Weather Element Forecast: Observations used in generation of statistical equations which are used to produce forecasts of weather elements, important input to SCRIBE and forecast system.
• Applications: EER (volcanic ash, spills, fires, etc.), air pollution and atmospheric chemistry, nowcasting, surface fields (SST, ice, snow, etc.)
Observing Systems used in Global DA
Upper-air sites(TEMP, PILOT, DROP)
Surface stations(SYNOP, ASYNOP,METAR)
Buoys and ships
Aircraft(BUFR, AIREP, AMDAR, ADS)
Wind profilers(NOAA network)
Polar-orbiting Satellites(NOAA-15,16,17,18,METOP-A; DMSP-F15; AQUA, TERRA;) Geostationary Satellites
(GOES-11,12, Meteosat-7,9; MTSAT-1R)
Observations assimilated at CMC
200kmx200km/time step7 MW channels
U,V at 10 meter over ocean
250kmx250km/time step87 IR channels
SSM/I DMSP-13
QUIKSCAT, ASCAT
AIRS
(750 m) Vertical hourlyU,VProfiler (NOAA Network)
~180 km boxes11 layers, per time step
U,VMODIS polar winds
(Aqua, Terra, Global & DB)
1.5o x 1.5o
11 layers, per time step
U,V
(IR, WV, VI, 3.9μ channels)
AMV’s(METEOSAT E-W, GOES E-W, MTSAT-1R)
2o x 2o 3-hourlyIM3 (6.7 µm)Water vapor channel GOES 11-12
250 km x 250 km
per time step
Ocean Land
AMSU-A 4-14 6-14
AMSU-B / MHS 2-5 3-4
ATOVS
NOAA 15-16-17-18-19, AQUA, METOP
1o x 1o x 50 hPaper time stepU, V, T
Aircraft
(BUFR, AIREP, AMDAR, ADS)
1 report / 6hT, (T-Td), ps, (U, V over water)Surface report
(SYNOP, SHIP, BUOYs)
28 levelsU, V, T, (T-Td), psRadiosonde/dropsonde
ThinningVariablesType
100kmx100km/time step
GPSRO (COSMIC, GRACE, GRAS) Refractivity 830km, per time step
Conventional ObservationsRadiosondes Surface reports
Aircraft reports
Passive remote sensing observations(polar-orbiting satellites)
AIRS
SSM/I
AMSU-A/B
Passive remote sensing observations
GOES radiances
AMVs
Active remote sensing observations
GPS-RO
Wind profilers
Scatterometers
Data Quality Monitoring
• Meteorological Centres such as CMC that run Numerical Weather Prediction (NWP) models can monitor the performance of instruments (e.g. aircraft sensors used in AMDAR) on a continuous and near real-time basis
• Monitoring is based on observed minus first guess values (innovations), as well as data rejection statistics, extracted from the operational data assimilation system
• Monitoring is performed for individual platform, station, as well as by various programs (e.g. E-AMDAR, NOAA Satellites, etc).
• Time evolution of innovations, as well as their statistical distribution are extremely powerful and useful tools
Monitoring of AIRS radiance data
Analysis & Prediction at CMC
• Environmental Emergency applications – dispersion modeling
– Nuclear and volcanic ash
– Release of hazardous chemicals
– National security issues
Challenges
• Data Access– Despite numerous dissemination channels– Unique solutions for each new observation/product
• Data Timeliness– Require data less than one hour old– Weather Waits For No Man .. or Satellite .. or Data Delivery System
• Maintaining a Super-Computer facility– Many modeling programs require access– Keeping up with computing advances
• Assimilation of new data– Takes a long time to assimilate new data– Human resources - Finding, hiring and keeping operational staff,
researchers etc.