Ohtake, H., M. Murakami, N. Orikasa, A. Hashimoto, A. Saito, and T. Kato, 2014: Statistical validation of a cloud resolving model using aircraft observations of orographic snow clouds. J. Meteor. Soc. Japan, 92, 287-304.
- Cold rain processes simulated with a non-hydrostatic cloud-resolving model developed by the Japan Meteorology Agency / Meteorological Research Institute and run at 1 km horizontal resolution (1-km-NHM) with a two-moment bulk parameterization scheme are validated using in-situ aircraft observations for orographic snow clouds.
- To statistically validate the cold rain processes simulated by the 1-km-NHM, aircraft observations collected during two winter seasons (March and December 2007, a total of 21 flights) over the Echigo Mountains are analyzed and compared with the model.
- The horizontal wind direction, wind speed, and vertical wind velocity exhibit reasonable agreement between the numerical simulations and the aircraft observations.
- The simulated liquid water contents at every height interval and over every analysis area are significantly underestimated compared to the aircraft observations (Fig.1).
- The ratios of simulated cloud ice number concentrations to snow number concentrations are less than unity and much smaller than the corresponding ratios obtained from the aircraft observations (Fig.2).
- This suggests that the overall conversion from cloud ice to snow in the 1-km-NHM, which occurs primarily through depositional growth, is faster than that in real clouds.