GNSS-Derived Path Delay: An Approach to Compute the Wet Tropospheric Correction for Coastal Altimetry

• Type: Article in International Scientific Journal
• Date: 2010

Authors

Joana Fernandes, MJ (Author) FCUP; Clara Lazaro (Author) FCUP; Alexandra L Nunes (Author) Other; Nelson Pires (Author) Other; Luisa Bastos (Author) FCUP; Virgilio B Mendes (Author) Other

Journal

Title: IEEE Geoscience and Remote Sensing Letters

Vol. 7 No. 3

Pages: 596-600

ISSN: 1545-598X

Publisher: IEEE

Indexing

ISI Web of Knowledge - 38 Citations

Scopus - 40 Citations

Scientific classification

FOS: Engineering and technology > Electrical engineering, Electronic engineering, Information engineering

Other information

Authenticus ID: P-003-58P

DOI: 10.1109/lgrs.2010.2042425

Abstract (EN): This letter presents an innovative method for computing the wet tropospheric correction for altimetry measurements in the coastal regions, where the measurements from the microwave radiometers (MWRs) onboard altimetric missions become invalid. The method, called Global Navigation Satellite System (GNSS)-derived Path Delay, gives an estimation of the correction, along with the associated mapping error, from the combination of independent zenith wet delay (ZWD) values obtained from the tropospheric delays derived at a network of coastal GNSS stations, from the MWR measurements acquired before land degradation, and from the European Centre for Medium-Range Weather Forecasts Deterministic Atmospheric Model. The wet tropospheric correction is estimated at each altimeter point with an invalid MWR value using a linear space-time objective analysis technique that takes into account the spatial and temporal variability of the ZWD field and the accuracy of each data set used. The method was applied in the South West European region for the whole Envisat data series, and the results are presented here. The uncertainty of the wet-delay estimates is below 1 cm, provided they are obtained for points at distances shorter than similar to 50 km from a GNSS station, and/or valid MWR measurements are available for the estimation. The method can be implemented globally and foster the use of satellite altimetry in coastal studies.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 5