The Accidental Tide Gauge: A GPS Reflection Case Study From Kachemak Bay, Alaska

Author

Larson, Kristine M. ; Ray, R.D. ; Nievinski, Felipe G. ; Freymueller, J.T.

Author_Institution

Dept. of Aerosp. Eng. Sci., Univ. of Colorado, Boulder, CO, USA

Volume

10

Issue

5

fYear

2013

fDate

Sept. 2013

Firstpage

1200

Lastpage

1204

Abstract

For the last decade, it has been known that reflected GPS signals observed with specialized instruments could be used to measure sea level. In this letter, data from an existing geodetic-quality GPS site near Kachemak Bay, Alaska, are analyzed for a one-year time period. Daily sea-level variations are more than 7 m. Tidal coefficients have been estimated and compared with coefficients estimated from records from a traditional tide gauge at Seldovia Harbor, ~ 30 km away. The GPS and Seldovia estimates of M₂ and S₂ coefficients agree to better than 2%; much of this residual can be attributed to true differences in the tide over 30 km as it propagates up Kachemak Bay. For daily mean sea levels the agreement is 2.3 cm. Because a standard geodetic GPS receiver/antenna is used, this GPS instrument can measure long-term sea-level changes in a stable terrestrial reference frame.

Keywords

Global Positioning System; geodesy; oceanographic regions; sea level; tides; Alaska; GPS Because; GPS instrument; GPS reflection case; GPS signals; Kachemak Bay; Seldovia Harbor; Seldovia estimates; accidental tide gauge; geodetic GPS antenna; geodetic GPS receiver; geodetic-quality GPS site; long-term sea-level changes; sea level; specialized instruments; terrestrial reference frame; tidal coefficients; Antenna measurements; Global Positioning System; Sea level; Sea measurements; Standards; Tides; Time series analysis; GPS; multipath; reflections; tide gauge;

fLanguage

English

Journal_Title

Geoscience and Remote Sensing Letters, IEEE

Publisher

ieee

ISSN

1545-598X

Type

jour

DOI

10.1109/LGRS.2012.2236075

Filename

6450045