Journal of Geodesy

, Volume 87, Issue 5, pp 439–448

Global empirical model for mapping zenith wet delays onto precipitable water

  • Yi Bin Yao
  • Bao Zhang
  • Shun Qiang Yue
  • Chao Qian Xu
  • Wen Fei Peng
Original Article

DOI: 10.1007/s00190-013-0617-4

Cite this article as:
Yao, Y.B., Zhang, B., Yue, S.Q. et al. J Geod (2013) 87: 439. doi:10.1007/s00190-013-0617-4


We can map zenith wet delays onto precipitable water with a conversion factor, but in order to calculate the exact conversion factor, we must precisely calculate its key variable \(T_\mathrm{m}\). Yao et al. (J Geod 86:1125–1135, 2012. doi:10.1007/s00190-012-0568-1) established the first generation of global \(T_\mathrm{m}\) model (GTm-I) with ground-based radiosonde data, but due to the lack of radiosonde data at sea, the model appears to be abnormal in some areas. Given that sea surface temperature varies less than that on land, and the GPT model and the Bevis \(T_\mathrm{m}\)\(T_\mathrm{s}\) relationship are accurate enough to describe the surface temperature and \(T_\mathrm{m}\), this paper capitalizes on the GPT model and the Bevis \(T_\mathrm{m}\)\(T_\mathrm{s}\) relationship to provide simulated \(T_\mathrm{m}\) at sea, as a compensation for the lack of data. Combined with the \(T_\mathrm{m}\) from radiosonde data, we recalculated the GTm model coefficients. The results show that this method not only improves the accuracy of the GTm model significantly at sea but also improves that on land, making the GTm model more stable and practically applicable.


GPS meteorology Zenith wet delay Precipitable water 

List of abbreviations


Constellation Observation System of Meteorology, Ionosphere, and Climate


Global Positioning System


Global Pressure and Temperature


Global \(T_\mathrm{m}\) model


Global Navigation Satellite System


European Centre for Medium-Range Weather Forecasts


Integrated Global Radiosonde Archive


Mean Absolute Error


Precipitable Water Vapor


Root Mean Square


Zenith Wet Delay

Supplementary material

190_2013_617_MOESM1_ESM.docx (24 kb)
Supplementary material 1 (docx 24 KB)

Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Yi Bin Yao
    • 1
  • Bao Zhang
    • 1
  • Shun Qiang Yue
    • 1
  • Chao Qian Xu
    • 1
  • Wen Fei Peng
    • 1
  1. 1.School of Geodesy and GeomaticsWuhan UniversityWuhanChina