Microwave radiometer SSM/I data and scatterometer QuikSCAT data have been widely used for the icesheet near-surface snowmelt detection based on their sensitivity to liquid water present in snow. In order to improve th...Microwave radiometer SSM/I data and scatterometer QuikSCAT data have been widely used for the icesheet near-surface snowmelt detection based on their sensitivity to liquid water present in snow. In order to improve the Antarctic ice-sheet near-surface snowmelt detection accuracy, a new Antarctic icesheet near-surface snowmelt synergistic detection method was proposed based on the principle of complementary advantages of SSM/I data(high reliability) and QuikSCAT data(high sensitivity) by the use of edge detection model to automatically extract the edge information to get the distribution of Antarctic snowmelt onset date, snowmelt duration and snowmelt end date. The verification result shows that the proposed snowmelt synergistic detection method improves the detection accuracy from about 75% to 86% based on AWS(Automatic Weather Stations) Butler Island and Larsen Ice Shelf. The algorithm can also be applied to other regions, which provides methodological support and supplement for the global snowmelt detection.展开更多
Since QuikSCAT is available in cloudy and rainy condition, its wind data are valuable in monitoring and real time forecasting the wind field, especially in sparse genesis regions of tropical cyclones. In order to unde...Since QuikSCAT is available in cloudy and rainy condition, its wind data are valuable in monitoring and real time forecasting the wind field, especially in sparse genesis regions of tropical cyclones. In order to understand and investigate the impact of QuikSCAT wind data, the three-dimensional variational data assimilation (3D-VAR) of scatterometric wind data has been employed for the tropical cyclone 'Vongfong' in the year 2002. The result shows that the QuikSCAT wind data have positive impact on the analysis and forecasting. But the positive impact is slight. The present results suggest that how to assimilate QuikSCAT wind data effectively is important and will be a challenge to meteorologists.展开更多
为评估由散射计资料反演的海面风场和海平面气压场对台风模拟的影响,使用中尺度天气研究与预报(Weather Research and Forecasting,WRF)模式和WRF三维变分同化系统,以2006年强热带风暴"Wukong"为例,把QuikSCAT风场资料代入华...为评估由散射计资料反演的海面风场和海平面气压场对台风模拟的影响,使用中尺度天气研究与预报(Weather Research and Forecasting,WRF)模式和WRF三维变分同化系统,以2006年强热带风暴"Wukong"为例,把QuikSCAT风场资料代入华盛顿大学行星边界层(The University of Washington Planetary Boundary Layer,UWPBL)模式反演得到的海平面气压场后,对海平面气压场进行同化研究,并与同化QuikSCAT风场结果进行对比。试验结果表明:同化海平面气压场在改进热带气旋的初始场和路径、强度预报方面,均较同化QuikSCAT海面风场资料效果要好。展开更多
As an approach to the technological problem that the wind data of QuikSCAT scatterometer cannot accurately describe the zone of typhoon-level strong wind speed, some objective factors such as the typhoon moving speed,...As an approach to the technological problem that the wind data of QuikSCAT scatterometer cannot accurately describe the zone of typhoon-level strong wind speed, some objective factors such as the typhoon moving speed, direction and friction are introduced in this study to construct the asymmetric strengthening of the QuikSCAT wind field. Then by adopting a technology of four-dimensional data assimilation, an experiment that includes both the assimilation and forecasting phases is designed to simulate Typhoon Rananim numerically. The results show that with model constraints and adjustment, this technology can incorporate the QuikSCAT wind data to the entire column of the model atmosphere, improve greatly the simulating effects of the whole-column wind, pressure field and the track as well as the simulated typhoon intensity covered by the forecast phase, and work positively for the forecasting of landfall locations.展开更多
基金supported by National Natural Science Foundation of China(Grant No. 41606209)supported by National Key Research and Development Program of China (Grant No. 2016YFB0501501)+3 种基金supported by Fujian Provincial Key Laboratory of Photonics Technology, Key Laboratory of Optoelectronic Science and Technology for Medicine of Ministry of Education, Fujian Normal University, China(Grant No. JYG1707)supported by Polar Science Strategic Research Foundation of China (Grant No. 20150312)supported by the Fundamental Research Funds for the Henan Provincial Colleges and Universities (Grant No. 2015QNJH16)supported by Science and technology project of Zhengzhou Science and Technology Bureau(Grant No. 20150251)
文摘Microwave radiometer SSM/I data and scatterometer QuikSCAT data have been widely used for the icesheet near-surface snowmelt detection based on their sensitivity to liquid water present in snow. In order to improve the Antarctic ice-sheet near-surface snowmelt detection accuracy, a new Antarctic icesheet near-surface snowmelt synergistic detection method was proposed based on the principle of complementary advantages of SSM/I data(high reliability) and QuikSCAT data(high sensitivity) by the use of edge detection model to automatically extract the edge information to get the distribution of Antarctic snowmelt onset date, snowmelt duration and snowmelt end date. The verification result shows that the proposed snowmelt synergistic detection method improves the detection accuracy from about 75% to 86% based on AWS(Automatic Weather Stations) Butler Island and Larsen Ice Shelf. The algorithm can also be applied to other regions, which provides methodological support and supplement for the global snowmelt detection.
文摘Since QuikSCAT is available in cloudy and rainy condition, its wind data are valuable in monitoring and real time forecasting the wind field, especially in sparse genesis regions of tropical cyclones. In order to understand and investigate the impact of QuikSCAT wind data, the three-dimensional variational data assimilation (3D-VAR) of scatterometric wind data has been employed for the tropical cyclone 'Vongfong' in the year 2002. The result shows that the QuikSCAT wind data have positive impact on the analysis and forecasting. But the positive impact is slight. The present results suggest that how to assimilate QuikSCAT wind data effectively is important and will be a challenge to meteorologists.
文摘为评估由散射计资料反演的海面风场和海平面气压场对台风模拟的影响,使用中尺度天气研究与预报(Weather Research and Forecasting,WRF)模式和WRF三维变分同化系统,以2006年强热带风暴"Wukong"为例,把QuikSCAT风场资料代入华盛顿大学行星边界层(The University of Washington Planetary Boundary Layer,UWPBL)模式反演得到的海平面气压场后,对海平面气压场进行同化研究,并与同化QuikSCAT风场结果进行对比。试验结果表明:同化海平面气压场在改进热带气旋的初始场和路径、强度预报方面,均较同化QuikSCAT海面风场资料效果要好。
基金National Key Fundamental Research and Development Plan of China (2004CB418301)Natural Science Foundation of China (40830958)
文摘As an approach to the technological problem that the wind data of QuikSCAT scatterometer cannot accurately describe the zone of typhoon-level strong wind speed, some objective factors such as the typhoon moving speed, direction and friction are introduced in this study to construct the asymmetric strengthening of the QuikSCAT wind field. Then by adopting a technology of four-dimensional data assimilation, an experiment that includes both the assimilation and forecasting phases is designed to simulate Typhoon Rananim numerically. The results show that with model constraints and adjustment, this technology can incorporate the QuikSCAT wind data to the entire column of the model atmosphere, improve greatly the simulating effects of the whole-column wind, pressure field and the track as well as the simulated typhoon intensity covered by the forecast phase, and work positively for the forecasting of landfall locations.
