| Abstract: | Cold-airflow snowfall in the southern part of the Liaodong Peninsula and its adjacent sea area may cause disastrous weather under the specific season, weather situations and conditions. In this case, improving the accuracy of cold-airflow snowfall forecast is of great significance to disaster prevention and mitigation in coastal areas. Using the daily precipitation data of each meteorological station in Liaoning and ERA5 reanalysis data from 1981 to 2021, this paper uses statistical and physical quantity diagnostic methods to analyze the climatic characteristics,causes and regularities of cold-airflow snowfall in the southern part of the Liaodong Peninsula. The results show that the intensity of snowfall in the southern part of the Liaodong Peninsula is weak,and it is mainly light snow. The number and the amount of cold-airflow snowfall are both more in the south and less in the north, and the former inter-annual variation is stable while the latter is obvious. The cold -airflow snowfall often occurs in December, while with stronger snowfall intensity in November and February. The generation of cold -airflow snowfall is closely related to the large air -sea temperature difference, unstable stratification in the lower layer, and the effect of sea-land topographic condition. In addition, when the influencing systems are cold eddy and low trough on the 500 hPa and 850 hPa weather charts, the lower layer is northerly wind with good relative humidity, and 1 000 hPa corresponds to positive relative vorticity in the southern part of the Liaodong Peninsula and its adjacent sea area,it can be predicted that cold-airflow snowfall may occur in the southern part of the Liaodong Peninsula. What`s more, the correlation coefficient further indicates that the difference between sea surface temperature and 850 hPa temperature directly determines the magnitude of cold-airflow snowfall. |
