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Using Simulated Satellite Imagery in NWS Experiments and Testbeds. Justin Sieglaff Wayne Feltz Tim Schmit Jordan Gerth Cooperative Institute for Meteorological Satellite Studies University of Wisconsin. What is simulated satellite imagery?. NSSL 4km WRF-ARW Run Daily at 00 UTC
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Using Simulated Satellite Imagery in NWS Experiments and Testbeds Justin Sieglaff Wayne Feltz Tim Schmit Jordan Gerth Cooperative Institute for Meteorological Satellite Studies University of Wisconsin
What is simulated satellite imagery? NSSL 4km WRF-ARW Run Daily at 00 UTC Vertical profiles of: T, q, 5 hydrometeors Surface Emissivity/Albedo Database + Radiative Transfer Model Brightness Temperatures and/or Reflectances for every WRF-ARW Pixel for a variety of satellite channels
Simulated Satellite Imagery • Why is simulated satellite imagery part of the GOES-R Proving Ground? • Prepare NWS forecasters for new capabilities of GOES-R, especially Advanced Baseline Imager (ABI) • Simulated satellite imagery is best for show casing new spectral bands (e.g.-three water vapor channels opposed to a single water vapor channel; remote sensing of water vapor in different layers of the troposphere) • Simulated satellite imagery also provides an integrated representation of the underlying NWP model solution – in a way meteorologists are familiar
Simulated Satellite Imagery Production • CIRA generates hourly output for forecast hours 9-36 (09 UTC Day 1 – 12 UTC Day 2) • ABI IR Bands: 3.9, 6.95, 7.34, 8.5, 10.35, 12.3 µm • Also provide select band differences • CIMSS generates hourly output for forecast hours 12-36 (12 UTC Day 1 – 12 UTC Day 2) • All ABI IR Bands 8-16 (6.19 – 13.3 µm) • ABI 0.64 µm (visible) channel for forecast hours 12-26 (12 UTC Day 1 – 02 UTC Day 2) • UW/CIMSS WRF Chem run is being run once daily in which all 16 ABI channels are simulated
A variety of uses • Following examples show how simulated satellite imagery is being used by forecasters at NWS experiments and testbeds • Verifying model solution accuracy • Convective Initiation • Jet/Vorticity Placement/Timing • Cloud development for aviation concerns • Sky cover and temperature forecasting
Convection: 08 June 2011 GOES-13 observation show existing convection over the western Great Lakes at 13 UTC 08 June 2011 Simulated 11 µm imagery at 13 UTC indicates NSSL WRF is verifying reasonably well compared to GOES observations Simulated WRF imagery shows existing convection will decay through the late morning with clearing skies over IA/southern WI by early afternoon Between 20-21 UTC the simulated WRF imagery indicates convection developing along a cold front, becoming intense and building southwest with time Given the WRF simulated imagery was shown to be in reasonable agreement with GOES observations at 13 UTC more confidence can be gained in the model solution GOES-13 observations show convection firing over southwestern Wisconsin between 20-21 UTC; with continued development and intensification southwestward into Iowa by the end of the afternoon The GOES-13 observations during the late morning and early afternoon also show decaying morning convection and subsequent clearing skies—lending more confidence to the WRF solution See also: Bikos, D., D. T. Lindsey, J. Otkin, J. Sieglaff, L. Grasso, C. Siewert, J. Correia, M. Coniglio, R. Rabin, J. S. Kain, and S. Dembek, 2012: Synthetic satellite imagery for real-time high-resolution model evaluation. Wea. Forecasting, 27, 784-795.
Convection: 06 June 2012 Convection Example with an aviation focus from the 2012 NOAA HWT. Forecaster was comparing simulated IR window imagery at 1900 UTC 06 June 2012 (top) to the observed GOES-13 IR observations from 1830 UTC 06 June 2012 (bottom) Forecaster noted simulated imagery was correctly identifying major pieces for afternoon convection forecast: Jet streak cirrus over Utah Clear skies and good insolation over central/eastern Colorado Clouds associated with upper level low over Kansas and northern OK Simulated IR window imagery indicates convection would develop over the foot hills and high plains of CO/WY/NE by 2200 UTC Forecaster noted, “...can see that at 22 UTC, should the forecast be right, that reroutes will definitely be in order!” GOES-13 observations from 2202 UTC 06 June 2012 (right) compared to simulated imagery valid at the same time (left) The WRF model solution, as depicted by the simulated imagery, the WRF solution “…did an excellent job in generating convection in southeastern Wyoming. The timing was maybe a touch off, but this is certainly acceptable for such a highly detailed guidance which ran the previous night!” See also: http://goesrhwt.blogspot.com/2012/06/cys-severe-storms-now-poppingand-simsat.html http://goesrhwt.blogspot.com/2012/06/cys-convective-initiation-and-impacts.html
Jet Streak/Vort Max: 18 Oct 2012 Simulated 6.95 µm imagery valid 1200 UTC 18 Oct 2012 Vs. GOES-13 6.5 µm imagery valid 1215 UTC 18 Oct 2012 Simulated imagery agrees well with GOES observations; implying WRF model is capturing jet streak/vorticity maxima placement correctly early in forecast cycle
Low Clouds: 19 Oct 2012 Simulated Visible Simulated Visible Observed Visible Simulated visible channel valid at 13-15 UTC 19 Oct 2012 suggests stratus clouds and/or fog are possible in portions of coastal Texas GOES-13 observations show WRF solution was reasonable (although missed northern extent of stratus) Observations indicate MVFR to IFR conditions due to ceilings and visibility
Low Temperature/Sky Cover: 19 Oct 2012 SREF guidance from 09 UTC 18 Oct 2012 valid at 12 UTC 19 Oct 2012 (27 hour forecast) indicates a ribbon of coldest temperatures (25-30F) over western ND, SD, and NE To increase confidence in this situation the simulated WRF imagery is investigated Simulated IR window imagery valid 12 UTC 19 Oct 2012 (36 hour forecast) shows a large cloud field associated with upper level low over the western Great Lakes Further west high clouds are confined to eastern ND/SD with low-level stratus or clear skies over central/western ND/SD/NE GOES-13 IR window observation at 1145 UTC 19 Oct 2012 matches up remarkably well with 36 hour forecasted simulated IR window imagery How does the low temperature from the SREF guidance verify? High clouds Forecast verification is quite good with 25-30F temperatures over western ND/SD/NE with warmer 30s and 40s further east Clear skies Low Clouds
Water Vapor at Different Layers GOES-R ABI will have three water vapor absorption channels instead of the current GOES single water vapor absorption channel. These channels are located in the IR spectrum between 6.0 and 7.5 µm; where water vapor absorption becomes weaker with increasing wavelength. This means GOES-R ABI will make observations of water vapor in three different layers of the troposphere. Get weighting functions in real-time for radiosonde stations! http://cimss.ssec.wisc.edu/goes/wf/
Additional Information See the GOES-R Proving Ground / NOAA Hazardous Weather Testbed Blog for more examples of how forecasters were using simulated imagery http://goesrhwt.blogspot.com Simulated imagery from CIRA is available in Eastern, Central, Southern, and Western Region LDMs http://rammb.cira.colostate.edu/ramsdis/online/goes-r_proving_ground.asp Simulated imagery from CIMSS is available in Central Region LDM as well as National Centers http://cimss.ssec.wisc.edu/goes_r/proving-ground/nssl_abi/nssl_abi_rt.html The simulated imagery is being provided as part of the GOES-R Proving Ground in an effort to ensure Day 1 User Readiness. What happens to simulated imagery when the GOES-R Proving Ground is complete? The usefulness of this data clearly extends past preparing for a future satellite instrument.
Questions? Thank you!!! Also would like to thank Dan Lindsey and Dan Bikos and others at CIRA for the collaborative effort of delivering GOES-R Proving Ground Simulated Satellite Imagery to NWS offices and experiments. Need more information for obtaining this data within AWIPS? Email: justin.sieglaff@ssec.wisc.edu