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Removing tidal-period variations from time-series data using low-pass digital filters

January 1, 1982

Several low-pass, digital filters are examined for their ability to remove tidal Period Variations from a time-series of water surface elevation for San Francisco Bay. The most efficient filter is the one which is applied to the Fourier coefficients of the transformed data, and the filtered data recovered through an inverse transform. The ability of the filters to remove the tidal components increased in the following order: 1) cosine-Lanczos filter, 2) cosine-Lanczos squared filter; 3) Godin filter; and 4) a transform fitter. The Godin fitter is not sufficiently sharp to prevent severe attenuation of 2–3 day variations in surface elevation resulting from weather events.

Publication Year 1982
Title Removing tidal-period variations from time-series data using low-pass digital filters
DOI 10.1175/1520-0485(1982)012<0112:RTPVFT>2.0.CO;2
Authors Roy A. Walters, Cynthia Heston
Publication Type Article
Publication Subtype Journal Article
Series Title Journal of Physical Oceanography
Index ID 70174408
Record Source USGS Publications Warehouse
USGS Organization San Francisco Bay-Delta; Pacific Regional Director's Office