RESEARCH
NUMERICAL ATMOSPHERIC MODELS FOR CLOUD AND PRECIPITATION PROCESSES
The double-moment approach for the bulk micro- physics scheme, which allows more flexibility of the size distribution enabling the mean diameter to evolve in contrast to the single-moment approach, is a promising method to improve the microphysical processes in the mesoscale modeling area; even though it requires more computational time than the single-moment approach by predicting mixing ratio and number concentration of hydrometeors.
AEROSOL EFFECTS ON THE EVOLUTION OF CONVECTIONS / REGIONAL CLIMATE
The impact of the initial aerosol concentration on the development of a convective storm can be evaluated by varying the number and mass of aerosols, reflected in the CCN number concentration, within a microphysics scheme. The change in averaged precipitation amount under different aerosol concentrations is not significant under the testbed of 3D mesoscale convective system configured in this study (Lim and Hong, 2012). Aerosol concentration does not change the mesoscale environment, but it does affect cloud microphysical budgets.
CLOUD RETRIEVAL ALGORITHM THROUGH MEASURED ATMOSPHERIC PROPERTIES
Retrieved cloud type classification: Classification is based on the cloud macro-physical quantities of cloud top, cloud base, and physical thickness of cloud layers, as measured by active sensors such as the millimeter wavelength cloud radar (MMCR) and micropulse lidar (MPL).
Retrieved fair-weather shallow cumulus (FWSC) events: Periods containing FWSC, a sub-category of clouds classified as low clouds, is produced using cloud fraction information from a total sky imager and ceilometer.
RADIOACTIVE POLLUTANT DISPERSION PREDICTION
Low-level wind fields play an important role in dispersion of air pollutants, including radionuclides. A substantial over-prediction bias at low-level wind speeds in the Weather Research and Forecasting model can be reduced by implementing orography parameterizations (JD12). With improved wind speed, radioactive pollutants are less dispersed.
