The Research Of Cold-air Snow On Shandong Peninsula

Cold-air winter snow is common in coastal areas of China's Bohai Sea as a weather phenomenon, a strong regional. There is often snows showers, and sometimes produces heavy snow. Using the WRF model simulation, cold-air processes on the Shandong Peninsula have been analyzed by conventional observational data,NECP1°×1°data,2.5°×2.5°NC data. We have mainly discussed the the role of high-altitude system in cold-air blizzard processes through PV. The results show that:(1) Early high SST cold has provided favorable conditions for cold-air occurrence. The difference between strong cold-air at low altitude and sea surface temperature is greater than above 20℃when Cold snow occurs. The cold-air of 850hPa layer has good relationship with ground precipitation intensity.(2) There is mainly NW wind fields on ground which makes cyclonic curve on peninsula. It provides burse mechanism for cold airstream course.(3) Vertical velocity and wind divergence illustrate a significant low-level resistance of cold-air process than other heavy rainfall.(4) From the experimental results of WRF sensitive test, different underlying surfaces of Shandong Peninsula and Liaodong Peninsula have a greater impact on the cold-air snow.(5) The high-altitude situation cold-air blizzard is divided into cold eddy and cross-slot behind cold eddy. There is more blizzards on cold eddy and average regional snowfall is larger; cold snow is extremely uneven distribution of snowfall. There is and uneven less blizzards on cross-slot groove and average regional snowfall is small.(6) PV of cold eddy is greater than that of cross-slot behind cold eddy, rising velocity of cold eddy is bigger and convective height is higher.(7) When the high and low altitude have formed PV column, and PV column has extended the altitude under 750hPa height, there is more likely to produce blizzard. Moreover, the the snowfall is stronger when the PV value is larger.