TWP-ICE/ACTIVE MONSOON CASE STUDY

Doppler velocity profiles based on measurements (white symbols) versus sample case study simulations (colored symbols):





Comments:

• Convective and stratiform areas in data and model results are identified at 3-km elevation from collocated C-pol radar data at 3 km elevation according to the algorithm described in `Climatological characterization of three-dimensional storm structure from operational radar and rain gauge data' by M. Steiner, R. A. Houze, Jr., and S. E. Yuter, Journal of Applied Meteorology, 34, 1978-2007, 1995. Profiles are means of reflectivities > 0 dBZ in columns identified as either convective or stratiform.
• S-band vertically pointing profiler (2835-MHz) data are supplied by Christopher Williams.
• S-band times identified as convective and stratiform using C-pol data.
• Values contributing to each altitude range plotted as a function of collocated reflecitivity:
  • model baseline, convective
  • model baseline, stratiform
  • model sensitivity, convective
  • model sensitivity, stratiform
• All measurement data have been downloaded from the DOE ARM data archive (www.arm.gov) and use in publications is subject to the policies described there.
• Model results are derived from fields reported at 3-hour frequency and 0.9-km resolution over a domain size of about 37,000 km².

Preliminary summary:

• The S-band observes deep, strong updrafts (directly over the instrument) only during event C (stratiform areas are observed during events A and B). Statistics for convective columns are poor for a vertically-pointing instrument over a two-week period, but stratiform areas are more uniform, more common, and better-sampled.