01-05 December 2025
INCOIS, Hyderabad, India.
| Abstract Submission No. | ABS-02-0043 |
| Title of Abstract | Vertical Kelvin wave propagation produced by a subsurface ridge |
| Authors | Dr. Laxmikant Dhage*, Dr. Ted Durland, Dr. Ted Strub, Dr. Vincent Combes |
| Organisation | INCOIS |
| Address | Indian National Centre for Ocean Information Services (INCOIS) Pragathi Nagar, Telangana, India Pincode: 500090 E-mail: laxmikant.d@incois.gov.in |
| Country | India |
| Presentation | Oral |
| Abstract | The vertical propagation of Coastal Trapped Waves (CTWs) due to subsurface ridges is explored with the help of linear numerical and analytical models. Results show that submerged ridges projecting from the shoreline can scatter a horizontally propagating single baroclinic mode Kelvin wave into both upward and downward propagating Kelvin wave (KW) beams, emanating from the ridge top. The semi-infinite shelf response to an incident single mode KW reveals alongshore dependence of the vertical structure in the form of multi-modal ridge-top KWs, suggesting that the width (alongshore extent) of the ridge is an important factor in determining the basin response past the ridge. We hypothesize that over narrow ridges (less than twice the Rossby radius of deformation on ridge-top), the trapped solutions at the edges of the ridges overlap and interact to transmit horizontally propagating energy into the surface layer of the downstream basin. At the same time narrow ridges result in a weaker subsurface peak in velocity next to the ridge top in the downstream basin. This decreases the amplitude of vertically propagating KW beams. The relative strengths of horizontally and vertically propagating KW modes are examined by using alongshore KW velocity profiles as a boundary condition near the ridge edge in the downstream basin. When the subsurface peaks in the vertical current profile are stronger, the basin response includes higher amplitudes of vertically propagating KW beams. Conversely, when the broader surface maximum is stronger, the horizontal energy propagation at the surface is higher. |
| Are you part of IIOE-2 endorsed project | no |
| Keywords | Kelvin Wave, Coastal Trapped Waves, Vertical Propogation |
| For Awards | no |