An Evaluation of GNSS Radio Occultation Technology for Australian Meteorology

Erjiang Fu, Kefei Zhang, Falin Wu, Xiaohua Xu, Kaye Marion, Anthony Rea, Yuriy Kuleshov, Gary Weymouth

Australian Bureau of Meteorology, Australia.
Surveying, Positioning and Navigation (SPAN) research group, RMIT University.

DOI:                 

Abstract

Earth atmospheric information has been primarily observed by a global network of radiosonde weather observation stations for global weather forecasting and climatologic studies for many years. However, the main disadvantage of this method is that it can not sufficiently capture the complex dynamics of the Earth’s atmosphere since its limited and heterogeneous geographic distribution of launching stations. Since the first low earth orbit (LEO) satellite equipped with a GPS receiver was launched in early 1990s, there are more than a dozen of GPS receivers onboard LEO satellites used for Earth atmospheric observation. Recent research has shown that the Global Navigation Satellite System (GNSS) radio occultation (RO) derived atmospheric profiles have great potentials to overcome many limitations of existing atmospheric observation methods. Constellation Observing Systems for Meteorology, Ionosphere, and Climate (COSMIC) retrieved atmospheric profiles are investigated using radiosonde measurements at 42 collocated stations in the Australian region. Statistical results show that the difference in average temperature is about 0.05 ?C with a standard deviation of 1.52?C and the difference in average pressure is -1.06 hPa with a standard deviation of 0.91 hPa. This research has also demonstrated that the GNSS RO derived atmospheric profiles have good agreement with the radiosonde observations.

Keywords

Radio Occultation, COSMIC, Radiosonde, GNSS.

Conflicts of Interest

The authors declare no conflicts of interest.

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