This research aims to study a distance variation of Precipitable Water Vapor(PWV) between Continuously Operating Reference Stations(CORS) in Thailand using a Precise Point Positioning(PPP) technique.Nowadays, Global N...This research aims to study a distance variation of Precipitable Water Vapor(PWV) between Continuously Operating Reference Stations(CORS) in Thailand using a Precise Point Positioning(PPP) technique.Nowadays, Global Navigation Satellite System(GNSS) CORS is not only used to obtain precise positioning applications but also plays an important role in meteorological applications. With a recent establishment of GNSS CORS around Thai region, the PWV can be accurately derived from these GNSS CORS data using the scientific Position and Navigation Data Analyst(PANDA) GNSS processing software. One-year period of GNSS CORS data collected between January 1 and December 31, 2016 are used in this study. The GNSS CORS data used in this study are gathered from various agencies, i.e. Chulalongkorn University,Department of Lands and Department of Public Works and Town & Country Planning. However, a coverage distance from each GNSS CORS for PWV estimations is not precisely determined for Thai region.This information can help reduce expenses in an installation and maintenance of meteorology sensors at each GNSS CORS. Therefore, this paper focuses on determining the distance variation of PWV between GNSS CORS and the coverage distance from each CORS for PWV estimations. The result shows that the coverage distance from each CORS at 74 km or less can provide accurate PWV in Thai region.展开更多
卫星导航定位连续运行参考站(continuously operating reference stations,CORS)系统作为GNSS与网络通信技术结合发展出的新兴导航定位CORS系统,具有快速高效、高精度、网络化等优点,不仅可以测量地表位置及运动,还可以借助GNSS信号的...卫星导航定位连续运行参考站(continuously operating reference stations,CORS)系统作为GNSS与网络通信技术结合发展出的新兴导航定位CORS系统,具有快速高效、高精度、网络化等优点,不仅可以测量地表位置及运动,还可以借助GNSS信号的折射与反射特征监测地表环境参数变化情况.本文提出一种将CORS站用于“积雪深度、土壤湿度、大气水汽、地表形变”的地表环境多参数综合监测体系,用以拓展CORS站在生态环境中的广泛应用.以齐齐哈尔市CORS站BFQE为实验案例,首先获取实验时段中CORS站接收的GNSS观测数据(含信噪比(signal to noise ratio,SNR)数据)、星历数据及气象数据对其进行预处理;其次对重采样的SNR数据采用非线性最小二乘及Lomb-Scargle谱分析方法解译特定时间段的浅层土壤湿度及地表积雪深度;然后通过联测远距离国际地球动力学服务机构站(International GPS Service for Geodynamics,IGS)采用相对定位技术获取测站的地表形变序列与大气水汽序列;最后,结合上述多种地表环境参数结果进行相关性分析,获得参数间的响应关系.实验结果表明:CORS站用于地表环境综合监测能够有效地监测多参数时间变化,反演得到的环境参数之间具有一定的响应关系.大气水汽含量会影响降雨的时空分布和强度,大气水汽反演值与降雨在趋势上呈现高度相关;在积雪时段,大气水汽的增加伴随着积雪深度的增加;大气水汽增加形成的降雨是土壤湿度的主要来源,解译土壤湿度总是在强降雨后呈现上升趋势,基于单星的土壤湿度与实测数据平均相关性为0.75,多星融合解译结果的相关性达到0.89,土壤含水率的均方根误差(root mean squared error,RMSE)为0.87%;地表形变时间序列在北(north,N)、东(east,E)方向形变较为稳定,天顶(up,U)方向的形变与大气水汽、积雪深度和土壤湿度存在一定的响应性波动.展开更多
文摘This research aims to study a distance variation of Precipitable Water Vapor(PWV) between Continuously Operating Reference Stations(CORS) in Thailand using a Precise Point Positioning(PPP) technique.Nowadays, Global Navigation Satellite System(GNSS) CORS is not only used to obtain precise positioning applications but also plays an important role in meteorological applications. With a recent establishment of GNSS CORS around Thai region, the PWV can be accurately derived from these GNSS CORS data using the scientific Position and Navigation Data Analyst(PANDA) GNSS processing software. One-year period of GNSS CORS data collected between January 1 and December 31, 2016 are used in this study. The GNSS CORS data used in this study are gathered from various agencies, i.e. Chulalongkorn University,Department of Lands and Department of Public Works and Town & Country Planning. However, a coverage distance from each GNSS CORS for PWV estimations is not precisely determined for Thai region.This information can help reduce expenses in an installation and maintenance of meteorology sensors at each GNSS CORS. Therefore, this paper focuses on determining the distance variation of PWV between GNSS CORS and the coverage distance from each CORS for PWV estimations. The result shows that the coverage distance from each CORS at 74 km or less can provide accurate PWV in Thai region.
文摘卫星导航定位连续运行参考站(continuously operating reference stations,CORS)系统作为GNSS与网络通信技术结合发展出的新兴导航定位CORS系统,具有快速高效、高精度、网络化等优点,不仅可以测量地表位置及运动,还可以借助GNSS信号的折射与反射特征监测地表环境参数变化情况.本文提出一种将CORS站用于“积雪深度、土壤湿度、大气水汽、地表形变”的地表环境多参数综合监测体系,用以拓展CORS站在生态环境中的广泛应用.以齐齐哈尔市CORS站BFQE为实验案例,首先获取实验时段中CORS站接收的GNSS观测数据(含信噪比(signal to noise ratio,SNR)数据)、星历数据及气象数据对其进行预处理;其次对重采样的SNR数据采用非线性最小二乘及Lomb-Scargle谱分析方法解译特定时间段的浅层土壤湿度及地表积雪深度;然后通过联测远距离国际地球动力学服务机构站(International GPS Service for Geodynamics,IGS)采用相对定位技术获取测站的地表形变序列与大气水汽序列;最后,结合上述多种地表环境参数结果进行相关性分析,获得参数间的响应关系.实验结果表明:CORS站用于地表环境综合监测能够有效地监测多参数时间变化,反演得到的环境参数之间具有一定的响应关系.大气水汽含量会影响降雨的时空分布和强度,大气水汽反演值与降雨在趋势上呈现高度相关;在积雪时段,大气水汽的增加伴随着积雪深度的增加;大气水汽增加形成的降雨是土壤湿度的主要来源,解译土壤湿度总是在强降雨后呈现上升趋势,基于单星的土壤湿度与实测数据平均相关性为0.75,多星融合解译结果的相关性达到0.89,土壤含水率的均方根误差(root mean squared error,RMSE)为0.87%;地表形变时间序列在北(north,N)、东(east,E)方向形变较为稳定,天顶(up,U)方向的形变与大气水汽、积雪深度和土壤湿度存在一定的响应性波动.
