This paper used potential height field data published by the China National Climate Center and the US NCEP reanalysis data. A study was conducted on a strong cold wave weather process in central and eastern China from...This paper used potential height field data published by the China National Climate Center and the US NCEP reanalysis data. A study was conducted on a strong cold wave weather process in central and eastern China from October 2 to 5, 2022. The results show that this weather process is a cold air weather process of “horizontal trough to vertical” type from the east of Novaya Zemlya Island. Cold air passes through Russia and Mongolia south, controlling northern China. The precipitation process is caused by the combination of high-altitude trough, ground front, warm and humid air flow, and precipitation weather formed by the influence of warm and humid air due to the 700 hPa shear line. The northern Sichuan Basin and the middle and lower reaches of the Yellow River in China can precipitate almost 50 mm. Water vapor is transported from the South China Sea to central and eastern China by the southwest warm and humid air flow along the west side of the West Pacific Subtropical High. Water vapor is concentrated over the precipitation area through horizontal convergence and is the most important source of water vapor causing precipitation.展开更多
An extensive rainfall occurred in central and eastern China during 23-24 April, 2021. This research mainly uses the reanalysis data of NCEP/NCAR every 6 hours to analyze this heavy rainfall weather process. The result...An extensive rainfall occurred in central and eastern China during 23-24 April, 2021. This research mainly uses the reanalysis data of NCEP/NCAR every 6 hours to analyze this heavy rainfall weather process. The results show that the main reason for this precipitation process is the shear formed between the cold air and the warm and humid air flow in the southwest. The low temperature on the ground allows the warm and humid air flow to lift up to form precipitation. The shear system is strengthened to a low vortex, which greatly strengthens the vertical ascent movement. Good water vapor and dynamic conditions form a large range of heavy rainfall.展开更多
The calculation theories and analysis methods of thermodynamic stability of embankment engineering in cold regions are systematically summarized.The engineering theories and methods taken to control frost heave and th...The calculation theories and analysis methods of thermodynamic stability of embankment engineering in cold regions are systematically summarized.The engineering theories and methods taken to control frost heave and thaw settlement in seasonal frozen soil regions may not be applicable in permafrost regions.The active cooling technology of roadbed should be utilized to limit the effects caused by both climate changes and human engineering activities.The paper mainly discussed the calculation theories and analysis methods of four kinds of embankment structures,i.e.,the crushed-rock embankment,duct-ventilated embankment,thermosyphon embankment,and composite embankment.It is expected that a scientific basis could be provided for the theory,design,and application of embankment constructions in cold regions.展开更多
文摘This paper used potential height field data published by the China National Climate Center and the US NCEP reanalysis data. A study was conducted on a strong cold wave weather process in central and eastern China from October 2 to 5, 2022. The results show that this weather process is a cold air weather process of “horizontal trough to vertical” type from the east of Novaya Zemlya Island. Cold air passes through Russia and Mongolia south, controlling northern China. The precipitation process is caused by the combination of high-altitude trough, ground front, warm and humid air flow, and precipitation weather formed by the influence of warm and humid air due to the 700 hPa shear line. The northern Sichuan Basin and the middle and lower reaches of the Yellow River in China can precipitate almost 50 mm. Water vapor is transported from the South China Sea to central and eastern China by the southwest warm and humid air flow along the west side of the West Pacific Subtropical High. Water vapor is concentrated over the precipitation area through horizontal convergence and is the most important source of water vapor causing precipitation.
文摘An extensive rainfall occurred in central and eastern China during 23-24 April, 2021. This research mainly uses the reanalysis data of NCEP/NCAR every 6 hours to analyze this heavy rainfall weather process. The results show that the main reason for this precipitation process is the shear formed between the cold air and the warm and humid air flow in the southwest. The low temperature on the ground allows the warm and humid air flow to lift up to form precipitation. The shear system is strengthened to a low vortex, which greatly strengthens the vertical ascent movement. Good water vapor and dynamic conditions form a large range of heavy rainfall.
基金supported by the Western Project Program of the Chinese Academy of Sciences(KZCX2-XB3-19)the National Natural Science Foundation of China(41230630)+2 种基金the National Basic Research Program of China(2012CB026102)the Knowledge Innovation Program of the Chinese Academy of Sciences(KZCX2-EW-QN301)the Project for Incubation of Specialists inGlaciology and Geocryology of the National Natural Science Foundation of China(J1210003/J0109)
文摘The calculation theories and analysis methods of thermodynamic stability of embankment engineering in cold regions are systematically summarized.The engineering theories and methods taken to control frost heave and thaw settlement in seasonal frozen soil regions may not be applicable in permafrost regions.The active cooling technology of roadbed should be utilized to limit the effects caused by both climate changes and human engineering activities.The paper mainly discussed the calculation theories and analysis methods of four kinds of embankment structures,i.e.,the crushed-rock embankment,duct-ventilated embankment,thermosyphon embankment,and composite embankment.It is expected that a scientific basis could be provided for the theory,design,and application of embankment constructions in cold regions.
