Publication Date:
2015-05-07
Description:
Satellite altimetry is regularly used to map the global distribution of mode-1 internal tides. Validating altimeter measurements of internal tides with in situ data is difficult as the mooring observations typically are too short compared with the altimetry. Here, taking advantage of the long-term (since 1999) TAO/TRITON buoy observations at 2 o S-156 o E located at a Topex/Poseiden (T/P) crossover in a region of strong internal tides, direct comparisons are made between altimeter and in situ measurements over a common 15-year period. The hourly buoy data are decimated every 9.9-day to emulate altimeter measurements. The altimeter and decimated buoy data are highly coherent at the aliased semidiurnal period (~60 day), and they agree well for the stationary semidiurnal internal tide. For the non-stationary internal tide, which consists of a significant annual cycle, the demodulated amplitude from the altimeter appears to be contaminated by non-tidal signals. The demodulated amplitude from the decimated buoy data, on the other hand, is capable of resolving the temporal variability. This suggests the potential of mapping non-stationary internal tides from satellites.
Print ISSN:
0094-8276
Electronic ISSN:
1944-8007
Topics:
Geosciences
,
Physics
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