Impacts of the High-Resolution Sea Surface Temperature Distribution on Modeled Snowfall Formation over the Yellow Sea during a Cold-Air Outbreak

High-resolution sea surface temperature (SST) products and idealized SST distributions were used to simulate snowfall over the Yellow Sea during 30-31 December 2007 using the Weather Research and Forecasting Model (WRF). Large differences were found between the SST distributions in the New Generation Sea Surface Temperature (NGSST) and Operational Sea Surface Temperature and Sea Ice Analysis (OSTIA) datasets near the Yellow Sea coast. Idealized SST datasets were defined to examine the influence of this difference in detail. The SST differences influenced the cloud streets and resultant snowfall formation. In simulations with the idealized SST distributions, convection developed and intensified later when the SST gradient was increased. In addition, the intensity of cloud streets was enhanced along the center of the flow. The simulations using the NGSST dataset showed widely distributed cloud streets and snowfall and heavier snowfall over the western Korean Peninsula, while those using the OSTIA dataset showed a concentrated distribution of cloud streets and snowfall along the center of airflow and more intense snowfall over North Jeolla Province, Korea, than in other regions. Comparing real SST products with observations qualitatively and quantitatively, OSTIA is found to have simulated the distribution and intensity of snowfall better than NGSST.