Research on Key Technologies of Precise InSAR Surveying and Mapping Applications Using Automatic SAR Imaging Xinming TANG,Tao LI,Xiaoming GAO,Qianfu CHEN,Xiang ZHANG Satellite Surveying and Mapping Application Centre,...Research on Key Technologies of Precise InSAR Surveying and Mapping Applications Using Automatic SAR Imaging Xinming TANG,Tao LI,Xiaoming GAO,Qianfu CHEN,Xiang ZHANG Satellite Surveying and Mapping Application Centre,Beijing 100048,China Abstract:Precise interferometric synthetic aperture radar (InSAR) is a new intelligent photogrammetric technology that uses automatic imaging and processing means.Precise InSAR has become the most efficient satellite surveying and mapping (SASM) method that uses the interferometric phase to create a global digital elevation model (DEM) with high precision.In this paper,we propose the application of systematic InSAR technologies to SASM.展开更多
The South Asian Summer Monsoon （SASM） is an important member of the monsoon system for Asia. It is made up of low-level subsystems of the Mascarene high in the Southern Hemisphere, cross-equatorial Somali jet stream...The South Asian Summer Monsoon （SASM） is an important member of the monsoon system for Asia. It is made up of low-level subsystems of the Mascarene high in the Southern Hemisphere, cross-equatorial Somali jet stream, 850-hPa westerly jet over the Arabian Sea, Indian monsoon trough north of the Bay of Bengal through west India and upper-level tropical easterly jet centered at 5°N and South Asia high centered at 30°N. During the summer monsoon, convection is intense in South Asia, with large scale and in association with abundant amount of latent heat release from condensation. Its anomalies affect not only the industrial and agricultural production and people＇s life in South Asia, but also the southwestern part of China. SASM is therefore drawing attention from quite a number of meteorologists from home and abroad. For instance, in their search for indicators of the summer monsoon in the region, Parthasarathy et al. Webster et al. and Goswami et al. defined a number of indexes based on precipitation and circulation. Wang et al.studied existing, widely-used indexes and came up with different regional indexes for the circulation and convection of SASM. Hahn et al.worked on the effect of topography on SASM. With wind field data, Wang et al. divided the years by the intensity of SASM and analyzed the characteristics of interannual variation and circulation for strong and weak years of monsoon. They found that the SASM intensified and weakened as a whole and there were four types of monsoon, being wholly strong and weak, stronger in the west than in the east and weaker in the west than in the east. Yan et al.discow,＇red sharp differences in individual members of the SASM at upper and lower levels over middle and lowe,r latitudes in both strong and weak years of the monsoon. Using, the dynamics method, Zhu et al. took the South Asia winter and summer monsoons as two stable equilibrium states and discussed the formation mechanism from the viewpoint of non-linear equilibrium theory. Their result further shows that in addition to thermal difference between land and sea, the topographic effect of South Asia also has significant restraints and influence on the formation and activity of the monsoon展开更多
The South Asian summer monsoon（SASM） precipitation is analyzed based on reanalysis datasets and historical simulation results from 23 climate models of the Coupled Model Intercomparison Project phase 5（CMIP5）. The...The South Asian summer monsoon（SASM） precipitation is analyzed based on reanalysis datasets and historical simulation results from 23 climate models of the Coupled Model Intercomparison Project phase 5（CMIP5）. The results show that most models reproduce well the climatological pattern of SASM precipitation, but the main rainfall period lags that of the reanalysis by one month. The relationship between the simulated SASM precipitation and sea surface temperature anomalies（SSTAs） is quite similar to the reanalysis data. This is attributed to the well-reproduced Walker cell anomaly in the tropical zone. It is projected that the negative correlation between SASM precipitation and SSTAs in the eastern equatorial Pacific will weaken and even reverse to a positive one in the period 2070–2096 under the representative concentration pathway（RCP） scenario with strong external forcing（RCP8.5）, while the change of the correlation under moderate forcing（RCP4.5） still has great uncertainty.展开更多
文摘Research on Key Technologies of Precise InSAR Surveying and Mapping Applications Using Automatic SAR Imaging Xinming TANG,Tao LI,Xiaoming GAO,Qianfu CHEN,Xiang ZHANG Satellite Surveying and Mapping Application Centre,Beijing 100048,China Abstract:Precise interferometric synthetic aperture radar (InSAR) is a new intelligent photogrammetric technology that uses automatic imaging and processing means.Precise InSAR has become the most efficient satellite surveying and mapping (SASM) method that uses the interferometric phase to create a global digital elevation model (DEM) with high precision.In this paper,we propose the application of systematic InSAR technologies to SASM.
文摘The South Asian Summer Monsoon （SASM） is an important member of the monsoon system for Asia. It is made up of low-level subsystems of the Mascarene high in the Southern Hemisphere, cross-equatorial Somali jet stream, 850-hPa westerly jet over the Arabian Sea, Indian monsoon trough north of the Bay of Bengal through west India and upper-level tropical easterly jet centered at 5°N and South Asia high centered at 30°N. During the summer monsoon, convection is intense in South Asia, with large scale and in association with abundant amount of latent heat release from condensation. Its anomalies affect not only the industrial and agricultural production and people＇s life in South Asia, but also the southwestern part of China. SASM is therefore drawing attention from quite a number of meteorologists from home and abroad. For instance, in their search for indicators of the summer monsoon in the region, Parthasarathy et al. Webster et al. and Goswami et al. defined a number of indexes based on precipitation and circulation. Wang et al.studied existing, widely-used indexes and came up with different regional indexes for the circulation and convection of SASM. Hahn et al.worked on the effect of topography on SASM. With wind field data, Wang et al. divided the years by the intensity of SASM and analyzed the characteristics of interannual variation and circulation for strong and weak years of monsoon. They found that the SASM intensified and weakened as a whole and there were four types of monsoon, being wholly strong and weak, stronger in the west than in the east and weaker in the west than in the east. Yan et al.discow,＇red sharp differences in individual members of the SASM at upper and lower levels over middle and lowe,r latitudes in both strong and weak years of the monsoon. Using, the dynamics method, Zhu et al. took the South Asia winter and summer monsoons as two stable equilibrium states and discussed the formation mechanism from the viewpoint of non-linear equilibrium theory. Their result further shows that in addition to thermal difference between land and sea, the topographic effect of South Asia also has significant restraints and influence on the formation and activity of the monsoon
基金Supported by the National(Key)Basic Research and Development(973)Program of China(2010CB950503)West Light Foundation of the Chinese Academy of Sciences(Y229D21001)National Natural Science Foundation of China(41130961)
文摘The South Asian summer monsoon（SASM） precipitation is analyzed based on reanalysis datasets and historical simulation results from 23 climate models of the Coupled Model Intercomparison Project phase 5（CMIP5）. The results show that most models reproduce well the climatological pattern of SASM precipitation, but the main rainfall period lags that of the reanalysis by one month. The relationship between the simulated SASM precipitation and sea surface temperature anomalies（SSTAs） is quite similar to the reanalysis data. This is attributed to the well-reproduced Walker cell anomaly in the tropical zone. It is projected that the negative correlation between SASM precipitation and SSTAs in the eastern equatorial Pacific will weaken and even reverse to a positive one in the period 2070–2096 under the representative concentration pathway（RCP） scenario with strong external forcing（RCP8.5）, while the change of the correlation under moderate forcing（RCP4.5） still has great uncertainty.
