A comparison of TWP-ICE observational data with cloud-resolving model results Academic Article uri icon


  • Observations made during the TWPICE campaign are used to drive and evaluate thirteen cloudresolving model simulations with periodic lateral boundary conditions. The simulations employ 2D and 3D dynamics, one and twomoment microphysics, several variations on largescale forcing, and the use of observationally derived aerosol properties to prognose droplet numbers. When domain means are averaged over a 6day active monsoon period, all simulations reproduce observed surface precipitation rate but not its structural distribution. Simulated fractional areas covered by convective and stratiform rain are uncorrelated with one another, and are both variably overpredicted by up to a factor of 2. Stratiform area fractions are strongly anticorrelated with outgoing longwave radiation (OLR) but are negligibly correlated with ice water path (IWP), indicating that ice spatial distribution controls OLR more than mean IWP. Overpredictions of OLR tend to be accompanied by underpredictions of reflected shortwave radiation (RSR). When there are two simulations differing only in microphysics scheme or largescale forcing, the one with smaller stratiform area tends to exhibit greater OLR and lesser RSR by similar amounts. After 10 days, simulations reach a suppressed monsoon period with a wide range of mean precipitable water vapor, attributable in part to varying overprediction of cloudmodulated radiative flux divergence compared with observationally derived values. Differences across the simulation ensemble arise from multiple sources, including dynamics, microphysics, and radiation treatments. Close agreement of spatial and temporal averages with observations may not be expected, but the wide spreads of predicted stratiform fraction and anticorrelated OLR indicate a need for more rigorous observationbased evaluation of the underlying micro and macrophysical properties of convective and stratiform structures.

published proceedings


author list (cited authors)

  • Fridlind, A. M., Ackerman, A. S., Chaboureau, J., Fan, J., Grabowski, W. W., Hill, A. A., ... Zhang, M.

citation count

  • 114

complete list of authors

  • Fridlind, AM||Ackerman, AS||Chaboureau, J-P||Fan, J||Grabowski, WW||Hill, AA||Jones, TR||Khaiyer, MM||Liu, G||Minnis, P||Morrison, H||Nguyen, L||Park, S||Petch, JC||Pinty, J-P||Schumacher, C||Shipway, BJ||Varble, AC||Wu, X||Xie, S||Zhang, M

publication date

  • March 2012