Evaluation of and Suggested Improvements to the WSM6 Microphysics in WRF-ARW Using Synthetic and Observed GOES-13 Imagery Lewis Grasso a Daniel T. Lindsey b , Kyo -Sun Lim c , Adam Clark d , Dan Bikos a , and Scott R. Dembek e
Evaluation of and Suggested Improvements to the WSM6 Microphysics in WRF-ARW Using Synthetic and Observed GOES-13 ImageryLewis Grassoa
Daniel T. Lindseyb, Kyo-Sun Limc, Adam Clarkd, Dan Bikosa, and Scott R. Dembeke
aCooperativeInstitute for Research in the Atmosphere (CIRA)
Colorado State University, Fort Collins, CO 80523-1375
bNOAACenter for Satellite Applications and ResearchcAtmospheric Sciences and Global Change DivisionPacific Northwest National LaboratorydNational Severe Storms Laboratory
eCooperative Institute for Mesoscale Meteorological Studies
High Impact Weather Workshop
1-3 April 2014, Norman, Oklahoma
Synthetic GOES-R 10.35 µm
Figure 1. (a) NSSL 4-km WRF-ARW synthetic imagery for the 10.35-µm (IR) band from the 0000 UTC 12 May 2010 model run valid at 1200 UTC. (b) GOES-13 10.7-µm (IR) band at 1232 UTC 12 May 2010. The brightness temperature scale (°C) is the same for the synthetic and GOES imagery. This figure is adapted from Bikos et al. (2012).
Bikos, D., D. T. Lindsey, J. Otkin, J. Sieglaff, L. Grasso, C. Siewert, J. Correlia Jr., 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.
Figure 2. Observed (a) and synthetic (b) 10.7 µm satellite imagery valid at 00 UTC on 11 April 2013, and histograms of observed (solid lines) and synthetic (dashed lines) brightness temperatures corresponding to the images over all brightness temperatures c) and zoomed in the denoted box for brightness temperatures between 190 K and 250 K (d). The synthetic image is based on a 24 hour forecast from the NSSL WRF.
Figure 3. Same as Figure 2, except valid at 04 UTC on 2 May 2013. The synthetic image is based on a 28-hour forecast from the NSSL WRF.
Figure 4. Same as Figure 2, except valid at 03 UTC on 16 July 2013. The synthetic image is based on a 27-hour forecast from the NSSL WRF.
Figure 5: Similar to the histograms in Figs 2-4, except for all 9- to 36-hour forecast images from July 2011 to May 2012.
Figure 6: Same as Figure 5, except from June 2012 to September 2012.
Figure 7: Synthetic GOES-R image at 10.35 µm valid 00Z 26 July 2013 for (a) the full domain and (b) zoomed over the white box shown in (a) over Texas, with locations of the horizontal and vertical cross sections indicated.
Figure 8: (a) Vertical cross section taken along the line Y=229, bounded between 495≤X≤535 as indicated in Figure 7b. All five WSM6 microphysical habits are contoured along with the freezing/melting and homogeneous freezing isotherms. (b) Synthetic 10.35 µm brightness temperatures (K) along the line Y=229.
Figure 9: Schematic of sources and sinks for each of the five microphysical habit types and water vapor in the WSM6 microphysical parameterization. The terms with red (blue) colors are activated when the temperature is above (below) 0 °C, whereas the terms with black color are in the entire regime of temperature.
SEN1: psacwand pgacw were reduced 50%.
psacw: accretion of cloud water by snow to snow
pgacw: accretion of cloud water by graupel to graupel
SEN2: psacw, pgacw, and psaut all reduced 50%.
psaut: self aggregationof ice to snow
SEN3: psacw, pgacw, psaut, psaci, pgaci, and, praci all reduced 50%.
psaci: accretion of ice by snow to snow
pgaci: accretion of ice by graupel to graupel
praci: accretion of ice by rain to snow or graupel