Detailed analysis and comparisons are made on the data of Hong Kong wind-profiler and the weather/precipitation every hour during the HUAMEX and the experiment for the monsoon of the South China Sea (SCSMEX) in 1998. ...Detailed analysis and comparisons are made on the data of Hong Kong wind-profiler and the weather/precipitation every hour during the HUAMEX and the experiment for the monsoon of the South China Sea (SCSMEX) in 1998. It is found that the wind-profiler data could reveal the meso-scale phenomena in the PBL of Southwest Monsoon, which was closely related to rainstorms. The center of the low-level jet under the altitude of 2 km, which corresponded to the appearance of heavy rain, appeared 1 to 2 hours after the center of low-level jet (LLJ) did above the 2-km altitude. An index I is designed to represent the intensity and height of the LLJ. This index can express clearly the close relationship between the precipitation and the LLJ. The results show that the wind-profiler is somewhat predictive to a rainstorm.展开更多
An empirical simulation method to simulate the possible position of shallow rainfall-induced landslides in China has been developed.This study shows that such a simulation may be operated in real-time to highlight tho...An empirical simulation method to simulate the possible position of shallow rainfall-induced landslides in China has been developed.This study shows that such a simulation may be operated in real-time to highlight those areas that are highly prone to rainfall-induced landslides on the basis of the landslide susceptibility index and the rainfall intensity-duration(I-D) thresholds.First,the study on landslide susceptibility in China is introduced.The entire territory has been classified into five categories,among which high-susceptibility regions(Zone 4-'High' and 5-'Very high') account for 4.15%of the total extension of China.Second,rainfall is considered as an external triggering factor that may induce landslide initiation.Real-time satellite-based TMPA3B42 products may provide real rainfall spatial and temporal patterns,which may be used to derive rainfall duration time and intensity.By using a historical record of 60 significant past landslides,the rainfall I-D equation has been calibrated.The rainfall duration time that may trigger a landslide has resulted between 3 hours and 45 hours.The combination of these two aspects can be exploited to simulate the spatiotemporal distribution of rainfall-induced landslide hazards when rainfall events exceed the rainfall I-D thresholds,where the susceptibility category is 'high' or 'very high'.This study shows a useful tool to be part of a systematic landslide simulation methodology,potentially providing useful information for a theoretical basis and practical guide for landslide prediction and mitigation throughout China.展开更多
基金A key project in Natural Science Foundation of China (980456032) Project 973 (G1998040907) Foundation Project for Visiting Scholar in Key Laboratory of Higher Education College
文摘Detailed analysis and comparisons are made on the data of Hong Kong wind-profiler and the weather/precipitation every hour during the HUAMEX and the experiment for the monsoon of the South China Sea (SCSMEX) in 1998. It is found that the wind-profiler data could reveal the meso-scale phenomena in the PBL of Southwest Monsoon, which was closely related to rainstorms. The center of the low-level jet under the altitude of 2 km, which corresponded to the appearance of heavy rain, appeared 1 to 2 hours after the center of low-level jet (LLJ) did above the 2-km altitude. An index I is designed to represent the intensity and height of the LLJ. This index can express clearly the close relationship between the precipitation and the LLJ. The results show that the wind-profiler is somewhat predictive to a rainstorm.
基金supported by the National Natural Science Foundation of China(Grant No.41501458)China Postdoctoral Science Foundation Funded Project(Grant No.2016M592860)+4 种基金National Basic Research Program of China(Grant No.2013CB733204)Key Laboratory of Mining Spatial Information Technology of NASMG(Grant Nos. KLM201309)Science Program of Shanghai Normal University(Grant No. SK201525)the Shanghai Gaofeng & Gaoyuan Project for University Academic Program Development(Grant Nos.2013LASW-A09 & SKHL1310)the Center of Spatial Information Science and Sustainable Development Applications,Tongji University,Shanghai,China
文摘An empirical simulation method to simulate the possible position of shallow rainfall-induced landslides in China has been developed.This study shows that such a simulation may be operated in real-time to highlight those areas that are highly prone to rainfall-induced landslides on the basis of the landslide susceptibility index and the rainfall intensity-duration(I-D) thresholds.First,the study on landslide susceptibility in China is introduced.The entire territory has been classified into five categories,among which high-susceptibility regions(Zone 4-'High' and 5-'Very high') account for 4.15%of the total extension of China.Second,rainfall is considered as an external triggering factor that may induce landslide initiation.Real-time satellite-based TMPA3B42 products may provide real rainfall spatial and temporal patterns,which may be used to derive rainfall duration time and intensity.By using a historical record of 60 significant past landslides,the rainfall I-D equation has been calibrated.The rainfall duration time that may trigger a landslide has resulted between 3 hours and 45 hours.The combination of these two aspects can be exploited to simulate the spatiotemporal distribution of rainfall-induced landslide hazards when rainfall events exceed the rainfall I-D thresholds,where the susceptibility category is 'high' or 'very high'.This study shows a useful tool to be part of a systematic landslide simulation methodology,potentially providing useful information for a theoretical basis and practical guide for landslide prediction and mitigation throughout China.
