New generation Doppler weather radar (NEXTRAD) has become one of the most important tools for monitoring and forecasting severe weather. It has been widely used in some developed countries. The construction of China’...New generation Doppler weather radar (NEXTRAD) has become one of the most important tools for monitoring and forecasting severe weather. It has been widely used in some developed countries. The construction of China’s NEXTRAD network has started since 1998, and this project is supported by national debt. In this paper the author addresses the development of NEXTRAD techniques, the pre\|sent situation of construction and application of NEXTRAD in China, some problems to be carefully considered in construction, and seve\|ral new fields of future radar technique developments and applications in weather monitoring.展开更多
A new regional dust model suitable for simula-tion and forecasting of dust storms over northern China was described. The dust model was developed by coupling the mesoscale dynamics model MM5 (the Fifth-Generation NCAR...A new regional dust model suitable for simula-tion and forecasting of dust storms over northern China was described. The dust model was developed by coupling the mesoscale dynamics model MM5 (the Fifth-Generation NCAR/Penn State Mesoscale Model) with a set of mass conservation equations for the particles. The model includes all the atmospheric physical processes of dust storms including occurrence, lifting, transport, and dry and wet deposition. It considers the parameterization of dry and wet deposition, the dust size distribution and microphysical processes in detail. The dust flux from the surface is parameterized based on the friction velocity, which is provided by the mesoscale nonhydrostatic dynamics model, which takes account of the vegetation coverage, land use, soil category, and soil moisture. This new dust model is used to simulate the dust storm that occurred on 1921 March, 2002 in North China. The results show that there is high dust concentration and its movement is consistent with the surface weather record and satellite monitoring images of the observed dust storm. The simulated dust concentration coincides with the observation data of the particulate concentration of PM10 (dust particles smaller than 10 m in diameter). The new numerical model also successfully simulates the formation and migration of the dust storm of 68 April, 2002 in North China.展开更多
文摘New generation Doppler weather radar (NEXTRAD) has become one of the most important tools for monitoring and forecasting severe weather. It has been widely used in some developed countries. The construction of China’s NEXTRAD network has started since 1998, and this project is supported by national debt. In this paper the author addresses the development of NEXTRAD techniques, the pre\|sent situation of construction and application of NEXTRAD in China, some problems to be carefully considered in construction, and seve\|ral new fields of future radar technique developments and applications in weather monitoring.
文摘A new regional dust model suitable for simula-tion and forecasting of dust storms over northern China was described. The dust model was developed by coupling the mesoscale dynamics model MM5 (the Fifth-Generation NCAR/Penn State Mesoscale Model) with a set of mass conservation equations for the particles. The model includes all the atmospheric physical processes of dust storms including occurrence, lifting, transport, and dry and wet deposition. It considers the parameterization of dry and wet deposition, the dust size distribution and microphysical processes in detail. The dust flux from the surface is parameterized based on the friction velocity, which is provided by the mesoscale nonhydrostatic dynamics model, which takes account of the vegetation coverage, land use, soil category, and soil moisture. This new dust model is used to simulate the dust storm that occurred on 1921 March, 2002 in North China. The results show that there is high dust concentration and its movement is consistent with the surface weather record and satellite monitoring images of the observed dust storm. The simulated dust concentration coincides with the observation data of the particulate concentration of PM10 (dust particles smaller than 10 m in diameter). The new numerical model also successfully simulates the formation and migration of the dust storm of 68 April, 2002 in North China.
