Evidence of inertially generated coastal-trapped waves in the eastern tropical Pacific

Observations of coastal‐trapped waves (CTW) are limited by instrumentation technologies and temporal and spatial resolutions; hence, their complete description is still limited. In the present work, we used measurements from high‐frequency radio scatterometers (HFR) to analyze the subinertial dynami...

Full description

Saved in:
Bibliographic Details
Published in:Journal of geophysical research. Oceans 2014-05, Vol.119 (5), p.3121-3133
Main Authors: Flores-Vidal, X., Durazo, R., Zavala-Sansón, L., Flament, P., Chavanne, C., Ocampo-Torres, F. J., Reyes-Hernández, C.
Format: Article
Language:English
Subjects:
Coastal environments
Coherence
Geophysics
Gulfs
Inertial
Marine
Meteorology
Oceanography
Oceans
Offshore
Offshore engineering
Oscillations
shelf
waves
wind
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Observations of coastal‐trapped waves (CTW) are limited by instrumentation technologies and temporal and spatial resolutions; hence, their complete description is still limited. In the present work, we used measurements from high‐frequency radio scatterometers (HFR) to analyze the subinertial dynamics of the Gulf of Tehuantepec in the Mexican Pacific, a region strongly influenced by offshore gap winds. The data showed subinertial oscillations that may be explained by poleward propagating CTWs. The oscillations showed higher coherence (95% confidence) with gap winds in the Gulfs of Papagayo and Panama than with local winds. Vertical thermocline oscillations, measured with a moored thermistor‐chain, also showed subinertial oscillations coherent with Papagayo and Panama winds. The period of the observed oscillations was ∼4 days, which corresponds to the inertial period of the Gulf of Panama. This suggests that inertial oscillations generated by offshore wind outbursts over Panama may have traveled northward along the coastal shelf, and were detected as surface current pulses by the HFR installed approximately 2000 km further north in the Gulf of Tehuantepec. To further explore the presence of CTWs, the 4 day band‐pass filtered currents measured by the HFR were analyzed using empirical orthogonal functions. We found that the first mode behaved like a CTW confined to the shelf break. Additionally, the observed oscillations were compared with baroclinic and barotropic CTW models. The results support the notion that nearly inertial baroclinic CTWs are generated in the Gulfs of Panama and Papagayo and then propagate toward the Gulf of Tehuantepec. Key Points Report evidence of a inertially generated coastal‐trapped waves Study the process that triggers coastal‐trapped waves in the tropical Pacific High‐frequency radars and its ability of detecting complex ocean features
ISSN:2169-9275
2169-9291
DOI:10.1002/2013JC009118