A Limited-area Model (LAM) Intercomparison Study of the TWP-ICE Case

Ping Zhu Florida International University
Ann Fridlind NASA - Goddard Institute for Space Studies
Jimy Dudhia NCAR
Paul Field UK Meteorological Office
Kathrin Wapler Deutscher Wetterdienst (German Meteorological Service)
Adam Varble University of Utah
Edward Zipser University of Utah
Zhenduo Zhu Florida International University
Ming Chen NCAR
Jon Petch UK Meteorological Office

Category: Modeling

Working Group: Cloud Life Cycle

The limited-area model (LAM) intercomparison described in this study is a unique component of the joint modeling study on tropical deep convective clouds organized by ARM/GCSS/SPARC. Multiple model configurations from three LAMs, namely WRF, UKMO-LAM, and COSMO, are used to simulate the TWP-ICE cloud case. The models are initialized and forced with ECMWF analyses. All models with different configurations are able to reproduce and maintain the observed thermodynamic structures. The diurnal variation of the convective cloud systems initiated by the mainland and islands is reasonably captured by the simulations. Models somehow also reproduced the observed cyclone genesis during the event C. However, models with different configurations show a substantial discrepancy on the simulated cloud fields despite the similar potential temperature and moisture profiles. The difference of ice water content, liquid water content, and rain water can be as large as a factor of 10. The dynamic field, particularly the vertical velocity, also shows a marked difference among the models. The sensitivity tests show that the simulated cloud fields and properties depend strongly on cloud microphysics schemes and vertical resolution.

This poster will be displayed at ASR Science Team Meeting.