Analysis of Meteorological Conditions for Fog and Haze in the Eastern and Central Regions of China during January, 2013

Based on the data of conventional meteorological observation, NCEP reanalysis data and atmospheric composition observation, a comprehensive analysis of the three kinds of persistent fog and haze in eastern China in January 2013 was carried out. The results show that the process of persistent fog and haze is in the background of static weather, and the zonal circulation in the middle and high latitudes is not conducive to the south of the cold air. In the eastern part of China, near-surface wind speed is low under the controlled of pressure field, which is conducive to the formation and maintenance of haze. The formation of inversion layer, the height of the mixed layer, the stratified structure of the upper dry layer, the ground wind speed and so on can represent the static stability of the atmosphere. In the actual forecast, fog and haze can be distinguished from the angle of relative humidity, PM2.5 concentration, diurnal variation characteristics, mixed layer height and energy structure, industrial structure and local and surrounding economic development level.

STUDY ON TYPHOON DISASTER LOSS AND RISK PREDICTION AND BENEFIT ASSESSMENT OF DISASTER PREVENTION AND MITIGATION

Based on the meteorological monitoring data of Typhoon Nesat and Haitang in Fujian Province in 2017, the data of the typhoon disaster situation and third-party evaluation of typhoon disaster prevention and mitigation benefit were investigated. By using the mean value anomaly estimation method in the similarity analysis method, it is estimated that typhoon Nesat and Haitang will cause direct economic losses of 0.8 ～ 1.8 billion yuan, and the typhoon disaster risk index evaluation model is used. The disaster risk pre-assessment of Typhoon Nesat and Haitang is carried out. The results of the study and analysis show that the pre-assessment results of Typhoon Nesat and Haitang are basically consistent with the actual disaster situation. The disaster loss was reduced to the minimum. According to the third party evaluation and investigation, it was concluded that the contribution rate of reducing economic benefits was 75% in Fujian Province for preventing and landing double typhoons Nesat and Haitang. Mainly reflected in the ship return to the port to avoid the wind, geological hazards prone to the site construction and cage culture danger removal reinforcement and other links; The contribution rate of reducing casualties is 86, mainly reflected in fishermen disembarkation and personnel transfer to safety emergency shelter and other links. The benefit of this double typhoon disaster prevention and mitigation in Fujian Province is about 0.6 billion yuan to reduce the direct economic loss. According to the investigation, the overall satisfaction of the double typhoon meteorological service is 91.0 points. Typhoon early warning information service convenience satisfaction is 91.4 points, early warning information accuracy satisfaction is 87.2 points, government departments strong anti-Taiwan disaster reduction organization, linkage departments participate in disaster prevention and mitigation high. However, there is a gap between public awareness and participation in typhoon disasters.