Modelling weighted mean temperature in the West African region: implications for GNSS meteorology

Meteorological applications

article

Olalekan Adekunle Isioye¹  Ludwig Combrinck¹  Joel Botai³ 

[1] Department of Geography, University of Pretoria;Hartebeesthoek Radio Astronomy Observatory (HartRAO);South African Weather Service

关键词: Global Navigation Satellite System (GNSS);    radiosonde;    NCEP/NCAR reanalysis;    precipitable water vapour (PWV);    Nigerian Weighted Mean Temperature Equation (NWMTE);    weighted mean temperature of the atmosphere;    GNSS meteorology;   

DOI  :  10.1002/met.1584

学科分类：社会科学、人文和艺术（综合）

来源: Wiley

【 摘 要 】

Weighted mean temperature ( T m ) is a critical parameter in the estimation of precipitable water vapour from ground-based Global Navigation Satellite System (GNSS) receivers. In the present study, three models of T m are developed for GNSS meteorological applications in the West African region in general and Nigeria in particular. The first is a least squares linear regression model based on National Centers for Environmental Prediction/National Center for Atmospheric Research reanalysis II data for Nigeria from 2010 to 2012. A regression of 37 330 data pairs of surface temperature and T m calculated from the vertical profiles of temperature above each grid node of the reanalysis model was used to produce the Nigerian Weighted Mean Temperature Equation-I (NWMTE-I) model after outlier data were removed. By using the same approach, NWMTE-II was obtained from 11 433 radiosonde profiles from 24 sounding stations in the West African region for the period 2009–2013. NWMTE-III was produced from a combination of the data used to build NWMTE-I and NWMTE-II. To evaluate the accuracy of these three models, they were compared with four global models based on T m obtained by using the integral method, which was the reference model for this study. The normalized mean absolute error, root-mean-square error, model efficiency, reliability index and correlation co-efficient were used as performance indicators. The performances of the developed models were promising compared with the global models, justifying the importance of using measured meteorological parameters when estimating T m and fine tuning T m to specific areas or regions. Finally, NWMTE-III is recommended for Nigerian users and NWMTE-II for users in the West African region.

【 授权许可】

CC BY|CC BY-NC|CC BY-NC-ND