A regime-dependent study of model performance at an Arctic cloud-observing site
Authors
Dan Lubin — Scripps Institution of Oceanography
Andrew M. Vogelmann — Brookhaven National Laboratory
Lynn M Russell — Scripps Institution of Oceanography
Johannes Muelmenstaedt — Center for Atmospheric Sciences and Physical Oceanography
Category
Warm Low Clouds and Interactions with Aerosol
Description
Two runs of a regional model were performed in the Arctic. The model runs differ in the cloud microphysical
scheme, with one run using a single-moment and the other a double-moment scheme. The models were initialized with GFS boundary conditions, and model results are compared with historical observations from the period 2003-2008 at the U.S. Department of Energy's Atmospheric Radiation Measurement (ARM) program North Slope of Alaska (NSA) site. Model success is evaluated based on the bias in several cloud-related variables. This analysis is performed separately by season and by meteorological regime, where the regimes are dened by the surface
meteorology at Barrow. For several cases, the causes of model biases and differences between the
microphysical schemes is examined more closely. This approach to model evaluation is meant to illustrate the power of a regime-based classification. Each case study comprises approximately 100 days. Thus, while the number of case studies remains manageable, the model is exposed to the intra- and interannual variability in ambient conditions.
