TWP-ICE/ACTIVE MONSOON CASE STUDY

Precipitation rate (PR) measurements (white lines and symbols) versus sample case study simulations (colored lines):



Comments:

• Forcing data set derived from variational analysis over the TWP-ICE domain bounded by sounding sites, provided by Shaocheng Xie and Minghua Zhang (summary with download link), reported as 3-hr mean values over the area of approximately 31,000 km².
• Precipitation rate retrievals from the C-Pol radar at Darwin are supplied by the Australian Bureau of Meteorology. Retrievals represent instantaneous values at a mean elevation of 2.5 km, reported at 10-min and 2.5-km resolution over an area of approximately 31,000 km².
• Disdrometer and bucket gauge data are supplied by Christopher Williams and are here averaged over 1 hour (rates from the two identical side-by-side bucket gauges are also averaged together). The Joss-Waldvogen disdrometer measures continuously over an area of 0.005 m2, and data are originally reported at 1-min resolution. The two bucket gauges measure continuously and data for each are originally reported as number of 0.01-inch tips per 10 s.
• ECMWF supplies hourly mean data at 0.56x0.56-degree resolution, from which mean values are plotted for the three grid boxes centered nearest to and immediately west of the Darwin ARM site, representing a total area of approximately 11,500 km².
• 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. Any errors in plotting or representation shown here should be blamed on Ann Fridlind.
• Model results are reported at 2.5-km resolution at an elevation of 2.5 km for comparison with forcing and radar data statistics (2nd and 3rd panels). For comparison with ECMWF data, at each 10-minute interval, the range of surface precipitation at 55-km resolution at the surface is shown as a vertical line.

Preliminary summary:

• The model tends to underpredict the highest domain-mean precipitation rates, but instantaneous peak rates tend to be overpredicted during the same events. It is difficult to draw conclusions from the disdrometer and bucket gauge point data regarding precipitation statistics owing to the mismatch in scales (time and space) and the short time period (14.5 days). ECMWF fields may show a tendency to miss large events and modestly underestimate peak precipitation rates during events that are captured.