TWP-ICE/ACTIVE MONSOON CASE STUDY
Cloud base height measurements and ECMWF results (white symbols) versus example case study simulations (colored lines):
Comments:
- ARSCL cloud base best estimate provided by Eugene Clothiaux represents a lidar-sensed cloud base.
- VISST IWP retrievals near the Darwin ARM site are provided at 4-km pixel resolution by Pat Minnis, derived from MTSAT measurements. We plot all retrievals centered within one degree latitude and within one degree longitude of the Darwin ARM site (results negligibly affected by reducing to a 0.5 degree margin).
- ECMWF supplies hourly mean data at 0.56x0.56-degree resolution, from which IWP is integrated ice condensate over all layers in each of the two grid boxes centered nearest to and immediately west of the Darwin ARM site at (130.43,-12.82) and (129.73,-12.47), both shown. The mean value is negligibly changed if a third grid box to the southeast at (131.13,-13.52) is also included (these three grid points are stored in the ARM archive for the Darwin site), bringing the total area to 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 instantaneous values reported at 3-hr frequency and 1-km resolution. When model results are averaged to lower resolution, the same definition of cloud boundary is applied after averaging to the lower resolution. Minimum to maximum range is shown (median value is given in legend).
- ARSCL and VISST cloud base estimates disagree widely, and simulations split the difference. Because ARSCL statistics are likely closest to ground truth, it appears that these simulations generally underestimate the presence of low cloud. There are also significant issues defining minimum cloud base.
