Precipitable Water Vapour Retrieval from GPS Precise Point Positioning and NCEP CFSv2 Dataset during Typhoon Events

Sensors

CraigMatthew Hancock¹  Huibde Ligt¹  Xu Tang¹  JonathanArthur Quaye-Ballard²  Yang Kong³  Hongkai Shi⁴  Zhiyong Xiang⁵ 

[1] Department of Civil Engineering, University of Nottingham Ningbo China, 199 Taikang East Road, Ningbo 315100, China;Department of Geomatic Engineering, Kwame Nkrumah University of Science and Technology (KNUST), Kumasi +233, Ghana;Ningbo Meteorological Bureau, 118 Qixiang Road, Ningbo 315100, China;School of Earth Science and Engineering, Hohai University, 8 Fochengxi Road, Nanjing 211100, China;The First Surveying and Mapping Institute of Zhejiang Province, Hangzhou 310012, China;

关键词: precise point positioning;    NCEP CFSv2;    CORS;    precipitable water vapour changes;    typhoon event;   

DOI  :  10.3390/s18113831

来源: DOAJ

【 摘 要 】

Radiosonde is extensively used for understanding meteorological parameters in the vertical direction. Four typhoon events, including three landfalls (MERANTI, NEPARTAK, and MEGI) and one non-landfall (MALAKAS), were chosen in analysing the precipitable water vapour (PWV) characteristics in this study. The spatial distribution of the three radiosonde stations in Zhejiang province does not meet the requirement in analysing changes in PWV during typhoon event. Global position system (GPS) observations are an alternative method for deriving the PWV. This enables improvements in the temporal⁻spatial resolution of PWV computed by the radiosonde measurements. The National Centers for Environmental Prediction (NCEP) re-analysed data were employed for interpolating temperature and atmosphere pressure at the GPS antennas height. The PWV computed from GPS observations and NCEP re-analysed data were then compared with the true PWV. The maximum difference of radiosonde and GPS PWV was not more than 30 mm at Taiz station. The Root-Mean-Square (RMS) of PWV differences between radiosonde and GPS was not more than 5 mm in January, February, March, November, and December. It was slightly greater than 5 mm in April. High RMS in May, June, July, August, September, and October implies that differences in GPS and radiosonde PWVs are evident in these months. Correlation coefficients of GPS and radiosonde PWVs were more than 0.9, indicating that the changes in GPS and radiosonde PWVs are similar. Radiosonde calculated PWVs were used for GPS PWV calibration for understanding the PWV changes during the period of a typhoon event. The results from three landfall typhoons show that the average PWV over Zhejiang province is increasing and approaching China mainland. In contrast, MALAKAS did not make landfall and shows a decreasing PWV trend, although it was heading to China mainland. Generally, the PWV change can be used to predict whether the typhoon will make landfall in these cases. PWV spatial distribution of MERANTI shows that PWV peaks change along the typhoon epicenter over Zhejiang province.

【 授权许可】

Unknown