On May 11,2011, the gale and dust weather appeared in Zhangjiakou City. By analyzing the conventional meteorological data, it was found that the gale and dust weather occurred by the combined effect of the cold air s...On May 11,2011, the gale and dust weather appeared in Zhangjiakou City. By analyzing the conventional meteorological data, it was found that the gale and dust weather occurred by the combined effect of the cold air splitting from the bottom of the high-altitude cold vortex and the Mongolian cyclone. The strong cold advection in the middle and lower layers provided the gale weather with driving force. The humidity conditions at middle and lower layers in Zhangjiakou City and its upstream region contributed to the weather process. Finally, the strong and wide rise district provided a more favorable power condition for the maintenance and transmission of the dust to the eastern region.展开更多
With the development of society and the acceleration of urbanization, urban heat island phenomenon is becoming increasingly prominent. In this paper, enrichment capacity of plant light energy is supplemented based on ...With the development of society and the acceleration of urbanization, urban heat island phenomenon is becoming increasingly prominent. In this paper, enrichment capacity of plant light energy is supplemented based on OKe model according to law of energy conservation. By contrasting each component of energy balance equation between the cities and rural areas, the causes for urban heat island are explained.展开更多
In order to understand the climatic change trend and characteristics of thunderstorm in Zhangjiakou City,and provide climate background basis for the thunder prevention and lightning disaster reduction in the region,o...In order to understand the climatic change trend and characteristics of thunderstorm in Zhangjiakou City,and provide climate background basis for the thunder prevention and lightning disaster reduction in the region,observation data of the thunderstorm at Zhangjiakou ground meteorological station from 1960 to 2013 were statistically analyzed by linear fitting,climate trend rate,M-K test,guaranteed rate method and so on. The results showed that the average annual thunderstorm days reached 37. 7 d in Zhangjiakou City from 1960 to 2013,and was in the moderate thunderstorm range. In nearly 54 years,thunderstorm day was reducing at the rate of about 1. 21 d /10 a in the city. There was thunderstorm in other three seasons except winter,and thunderstorm frequently occurred in summer. Summer thunderstorm day was reducing at the rate of about 1. 29 d /10 a,which caused the reduction of the annual one. In summer,thunderstorm day of July reduced most significantly. There were two key points of abrupt reduction,which occurred in 1971 and 1998,on the change of thunderstorm days in Zhangjiakou in recent 54 years. The first thunderstorm date had an advancing trend in recent years,while the final date had not an obvious change. The possibility of thunderstorm was very small from late October to next March in Zhangjiakou City. The first thunderstorm date occurred mostly before middle May,and the period from middle and late May to early and middle September was the high incidence of thunderstorm. The thunderstorm occurred mostly in the NW direction,with the least in E and SE directions,and dissipated mostly in SE direction,with the least in NW and W directions.展开更多
文摘On May 11,2011, the gale and dust weather appeared in Zhangjiakou City. By analyzing the conventional meteorological data, it was found that the gale and dust weather occurred by the combined effect of the cold air splitting from the bottom of the high-altitude cold vortex and the Mongolian cyclone. The strong cold advection in the middle and lower layers provided the gale weather with driving force. The humidity conditions at middle and lower layers in Zhangjiakou City and its upstream region contributed to the weather process. Finally, the strong and wide rise district provided a more favorable power condition for the maintenance and transmission of the dust to the eastern region.
文摘With the development of society and the acceleration of urbanization, urban heat island phenomenon is becoming increasingly prominent. In this paper, enrichment capacity of plant light energy is supplemented based on OKe model according to law of energy conservation. By contrasting each component of energy balance equation between the cities and rural areas, the causes for urban heat island are explained.
基金Supported by Science Research Development Item of Hebei Provincial Meteorological Bureau,China(11ky22)
文摘In order to understand the climatic change trend and characteristics of thunderstorm in Zhangjiakou City,and provide climate background basis for the thunder prevention and lightning disaster reduction in the region,observation data of the thunderstorm at Zhangjiakou ground meteorological station from 1960 to 2013 were statistically analyzed by linear fitting,climate trend rate,M-K test,guaranteed rate method and so on. The results showed that the average annual thunderstorm days reached 37. 7 d in Zhangjiakou City from 1960 to 2013,and was in the moderate thunderstorm range. In nearly 54 years,thunderstorm day was reducing at the rate of about 1. 21 d /10 a in the city. There was thunderstorm in other three seasons except winter,and thunderstorm frequently occurred in summer. Summer thunderstorm day was reducing at the rate of about 1. 29 d /10 a,which caused the reduction of the annual one. In summer,thunderstorm day of July reduced most significantly. There were two key points of abrupt reduction,which occurred in 1971 and 1998,on the change of thunderstorm days in Zhangjiakou in recent 54 years. The first thunderstorm date had an advancing trend in recent years,while the final date had not an obvious change. The possibility of thunderstorm was very small from late October to next March in Zhangjiakou City. The first thunderstorm date occurred mostly before middle May,and the period from middle and late May to early and middle September was the high incidence of thunderstorm. The thunderstorm occurred mostly in the NW direction,with the least in E and SE directions,and dissipated mostly in SE direction,with the least in NW and W directions.