To exploit cloud water resources to increase precipitation on the ground effectively,according to the principles of artificial precipitation enhancement,based on historical data of weather and precipitation from Fuxin...To exploit cloud water resources to increase precipitation on the ground effectively,according to the principles of artificial precipitation enhancement,based on historical data of weather and precipitation from Fuxin National Basic Meteorological Stations from 1981 to 2010,the distribution characteristics of cloud water resources,potential and countermeasures of artificial precipitation enhancement in Fuxin region of Liaoning Province were studied. The results show that the annual average quantity of cloud water resources in the air over Fuxin region over the past 30 years was 285. 6 × 10~8m^3,but the annual average precipitation was only 471.8 mm( amounting to 47.2 ×10~8m^3 of water resources),accounting for only16. 5% of total quantity of cloud water resources in the air; 12 times of artificial precipitation enhancement operation experiments were carried out by using the weather models and technical indicators suitable for artificial precipitation enhancement in Fuxin region,and the artificial precipitation efficiency was 18. 3% on average,5. 2% higher than before,and the annual average precipitation could increase by 2. 5 × 10~8m^3 approximately. All of these have great significance for implementing artificial precipitation enhancement operation scientifically and effectively,maximizing the exploitation of cloud water resources in the air,increasing total quantity of water resources,and mitigating drought in Fuxin region.展开更多
Based on statistical amount of traffic and weather data sets from three weigh-in-motion sites for the study period of from 2005 to 2009, permanent traffic counters and weather stations in Alberta, Canada, an investiga...Based on statistical amount of traffic and weather data sets from three weigh-in-motion sites for the study period of from 2005 to 2009, permanent traffic counters and weather stations in Alberta, Canada, an investigation is carried out to study impacts of winter weather on volume of passenger car and truck traffic. Multiple regression models are developed to relate truck and passenger car traffic variations to winter weather conditions. Statistical validity of study results are confirmed by using statistical tests of significance. Considerable reductions in passenger car and truck volumes can be expected with decrease in cold temperatures. Such reductions are higher for passenger cars as compared to trucks. Due to cold and snow interactions, the reduction in car and truck traffic volume due to cold temperature could intensify with a rise in the amount of snowfall. For passenger cars, weekends experience higher traffic reductions as compared to weekdays. However, the impact of weather on truck traffic is generally similar for weekdays and weekends. Interestingly, an increase in truck traffic during severe weather conditions is noticed at one of the study sites. Such phenomenon is found statistically significant. None of the past studies in the literature have presented the possibility of traffic volume increases on highways during adverse weather conditions;which could happen due to shift of traffic from parallel roads with inadequate winter maintenance programs. It is believed that the findings of this study can benefit highway agencies in developing such programs and policies as efficient monitoring of passenger car and truck traffic, and plan for efficient winter roadway maintenance programs.展开更多
By analyzing meteorological data during 2000 -2009, the characteristics of fog in Changzhi region and weather situation of fog weather occurrence were summarized, and forecast equation was established.
基金Supported by Science and Technology Planning Project for social development in Fuxin City of Liaoning Province(20151305)
文摘To exploit cloud water resources to increase precipitation on the ground effectively,according to the principles of artificial precipitation enhancement,based on historical data of weather and precipitation from Fuxin National Basic Meteorological Stations from 1981 to 2010,the distribution characteristics of cloud water resources,potential and countermeasures of artificial precipitation enhancement in Fuxin region of Liaoning Province were studied. The results show that the annual average quantity of cloud water resources in the air over Fuxin region over the past 30 years was 285. 6 × 10~8m^3,but the annual average precipitation was only 471.8 mm( amounting to 47.2 ×10~8m^3 of water resources),accounting for only16. 5% of total quantity of cloud water resources in the air; 12 times of artificial precipitation enhancement operation experiments were carried out by using the weather models and technical indicators suitable for artificial precipitation enhancement in Fuxin region,and the artificial precipitation efficiency was 18. 3% on average,5. 2% higher than before,and the annual average precipitation could increase by 2. 5 × 10~8m^3 approximately. All of these have great significance for implementing artificial precipitation enhancement operation scientifically and effectively,maximizing the exploitation of cloud water resources in the air,increasing total quantity of water resources,and mitigating drought in Fuxin region.
文摘Based on statistical amount of traffic and weather data sets from three weigh-in-motion sites for the study period of from 2005 to 2009, permanent traffic counters and weather stations in Alberta, Canada, an investigation is carried out to study impacts of winter weather on volume of passenger car and truck traffic. Multiple regression models are developed to relate truck and passenger car traffic variations to winter weather conditions. Statistical validity of study results are confirmed by using statistical tests of significance. Considerable reductions in passenger car and truck volumes can be expected with decrease in cold temperatures. Such reductions are higher for passenger cars as compared to trucks. Due to cold and snow interactions, the reduction in car and truck traffic volume due to cold temperature could intensify with a rise in the amount of snowfall. For passenger cars, weekends experience higher traffic reductions as compared to weekdays. However, the impact of weather on truck traffic is generally similar for weekdays and weekends. Interestingly, an increase in truck traffic during severe weather conditions is noticed at one of the study sites. Such phenomenon is found statistically significant. None of the past studies in the literature have presented the possibility of traffic volume increases on highways during adverse weather conditions;which could happen due to shift of traffic from parallel roads with inadequate winter maintenance programs. It is believed that the findings of this study can benefit highway agencies in developing such programs and policies as efficient monitoring of passenger car and truck traffic, and plan for efficient winter roadway maintenance programs.
文摘By analyzing meteorological data during 2000 -2009, the characteristics of fog in Changzhi region and weather situation of fog weather occurrence were summarized, and forecast equation was established.
