National Centers for Environment Prediction (NCEP) reanalysis data, automatic observation data, FY-2E satellite data and Doppler radar data are used to analyze a short-time local heavy rain in Yulin city, Shaanxi, Chi...National Centers for Environment Prediction (NCEP) reanalysis data, automatic observation data, FY-2E satellite data and Doppler radar data are used to analyze a short-time local heavy rain in Yulin city, Shaanxi, China on August 7, 2018. The result shows that the strong convective weather occurred in peripheral subtropical high over west pacific, being caused by short wave disturbance, and surface convergence lines with positive pressure variation are corresponding to areas of short-time heavy precipitation. The degree of temperature change in cold pool caused by thunderstorm may decide the intensity of a short-time rainfall, and local topography plays an important role in extreme precipitation. Local water vapour accumulation and water vapour flux convergence in the middle and lower layers support adequate moisture condition in the process. Moving direction and development direction of mesocale convective cloud are in a line to develop the train effect, leading to local short-time heavy rain in Yulin city, Shaanxi, China.展开更多
The dynamical-wave routing model of the urban unsteady and non-pressure rain pipe flow was established by conservation of mass, momentum and energy, and it was solved by applying the four point implicit difference met...The dynamical-wave routing model of the urban unsteady and non-pressure rain pipe flow was established by conservation of mass, momentum and energy, and it was solved by applying the four point implicit difference method and the pursuit method. It was obtained from the experiment checking and comparative analysis that the dynamical-wave muting model can reflect influence like attenuate and backwater when flood peak propagate in pipeline with high calculation precision and vast application scope, and it can be applied in routing of urban rain pipe flow of different slopes and inflow conditions. The routing model supplies a scientific foundation for the town rainfall piping design or checking, disaster administration of storm runoff, and so on.展开更多
文摘National Centers for Environment Prediction (NCEP) reanalysis data, automatic observation data, FY-2E satellite data and Doppler radar data are used to analyze a short-time local heavy rain in Yulin city, Shaanxi, China on August 7, 2018. The result shows that the strong convective weather occurred in peripheral subtropical high over west pacific, being caused by short wave disturbance, and surface convergence lines with positive pressure variation are corresponding to areas of short-time heavy precipitation. The degree of temperature change in cold pool caused by thunderstorm may decide the intensity of a short-time rainfall, and local topography plays an important role in extreme precipitation. Local water vapour accumulation and water vapour flux convergence in the middle and lower layers support adequate moisture condition in the process. Moving direction and development direction of mesocale convective cloud are in a line to develop the train effect, leading to local short-time heavy rain in Yulin city, Shaanxi, China.
基金Hunan Provincial Education Department of Key Projects(No.08A019)Funded Projects in Hunan Science and Technology Department(No.2008SK4029)
文摘The dynamical-wave routing model of the urban unsteady and non-pressure rain pipe flow was established by conservation of mass, momentum and energy, and it was solved by applying the four point implicit difference method and the pursuit method. It was obtained from the experiment checking and comparative analysis that the dynamical-wave muting model can reflect influence like attenuate and backwater when flood peak propagate in pipeline with high calculation precision and vast application scope, and it can be applied in routing of urban rain pipe flow of different slopes and inflow conditions. The routing model supplies a scientific foundation for the town rainfall piping design or checking, disaster administration of storm runoff, and so on.