An improved retrieval method, which uses the solution with a Gaussian constraint as the initial state variables for the Kalman Filtering (KF) method, was developed to retrieve the wet refractivity profiles from slan...An improved retrieval method, which uses the solution with a Gaussian constraint as the initial state variables for the Kalman Filtering (KF) method, was developed to retrieve the wet refractivity profiles from slant wet delays (SWD) extracted by the double-differenced (DD) GPS method. The accuracy of the GPS-derived SWDs is also tested in this study against the measurements of a water vapor radiometer (WVR) and a weather model. It is concluded that the GPS-derived SWDs have similar accuracy to those measured with WVR and are much higher in quality than those derived from the weather model used. The developed method is used to retrieve the 3D wet refractivity distribution in the Hong Kong region. The retrieved profiles agree well with the radiosonde observations, with a difference of about 4 mm km^- 1 in the low levels. The accurate profiles obtained with this method are applicable in a number of meteorological applications.展开更多
Based on meteorological field and air quality observation data, air pollution process over Pearl River Delta (PRD) in August of 2012 was analyzed. There were five notable pollution processes in this month, in which ...Based on meteorological field and air quality observation data, air pollution process over Pearl River Delta (PRD) in August of 2012 was analyzed. There were five notable pollution processes in this month, in which four pollution processes were related to typhoon. By using meso-scale meteorological model WRF, meteorological characteristics of two pollution processes induced by tropical cyclone were contrasted and analyzed. Results showed that O9 and PMTo concentrations significantly increased in PRD region during Typhoon Haikui period (7 -8 August), and other pollutant concentrations were also high. However, 03 and PM10 concentrations did not significantly increase during Typhoon Kai-Tak period (16 -17 August). This kind of concentration difference between two processes was related to typhoon pathway, wind direction and velocity, atmospheric boundary layer height, vertical transport and horizontal divergence field.展开更多
文摘An improved retrieval method, which uses the solution with a Gaussian constraint as the initial state variables for the Kalman Filtering (KF) method, was developed to retrieve the wet refractivity profiles from slant wet delays (SWD) extracted by the double-differenced (DD) GPS method. The accuracy of the GPS-derived SWDs is also tested in this study against the measurements of a water vapor radiometer (WVR) and a weather model. It is concluded that the GPS-derived SWDs have similar accuracy to those measured with WVR and are much higher in quality than those derived from the weather model used. The developed method is used to retrieve the 3D wet refractivity distribution in the Hong Kong region. The retrieved profiles agree well with the radiosonde observations, with a difference of about 4 mm km^- 1 in the low levels. The accurate profiles obtained with this method are applicable in a number of meteorological applications.
基金Supported by National Natural Science Foundation,China(41275100)Public Sector(Meteorological)Scientific Research Project,China(GYHY201306042,GYHY201406031)
文摘Based on meteorological field and air quality observation data, air pollution process over Pearl River Delta (PRD) in August of 2012 was analyzed. There were five notable pollution processes in this month, in which four pollution processes were related to typhoon. By using meso-scale meteorological model WRF, meteorological characteristics of two pollution processes induced by tropical cyclone were contrasted and analyzed. Results showed that O9 and PMTo concentrations significantly increased in PRD region during Typhoon Haikui period (7 -8 August), and other pollutant concentrations were also high. However, 03 and PM10 concentrations did not significantly increase during Typhoon Kai-Tak period (16 -17 August). This kind of concentration difference between two processes was related to typhoon pathway, wind direction and velocity, atmospheric boundary layer height, vertical transport and horizontal divergence field.