Topographic Rossby waves at a site north of the Gulf Stream
Abstract
The Woods Hole Oceanographic Institution has maintained buoys with current meters at Site D (39° 20'N, 70°W) for over three years, though there are large gaps in the record. Using a new spectral estimation technique, evidence is found in the data for strong topographic Rossby waves at depths of 500 m and more. For periods of about 2 days to 2 weeks, the spectra drop with a "— 3" power law, which is to be expected for a two-dimensional inertial subrange. Significant coherences of 0·6 and up are common between depths and between the velocity components at each depth. The motions at the three depths are nearly in phase. The velocity components at each level are nearly out of phase, giving significant down-slope momentum flux. A numerical model supports the suggestion that the observed coherent waves are driven by random forcing from the Gulf Stream decay region, and filtered by the large depth-change of the slope.
- Publication:
-
Deep Sea Research A
- Pub Date:
- 1971
- DOI:
- 10.1016/0011-7471(71)90011-8
- Bibcode:
- 1971DSRA...18....1T