DynmodesShear

Computes the vertical ocean dynamic modes with background currents U and stratification Nsq

%Yannis Cuypers LOCEAN Sorbonne Université 07/2022

computes the vertical oceanic baroclinic modes with background currents U and

startification Nsq (extends dynmodes https://github.com/sea-mat/dynmodes by J. Klinck to the presence of background current). Dynmodes (included in the package is used to get a first guess of the mode phase speed.

Function call:

[Wmod,Pmod,c]=dynmodesShear(Nsq,U,p,nmode)

Nsq (rad/s)^2 and U(m/s) are vectors varying with depth/pressure

(same size as p), p vector of pressure in dbar

nmode= mode number

Wmod,Pmod vertical mode strcture for pressure (Horizontal velocity) and vertical velocity

and phase speed c for the mode nmode

based on Thompson Haskell computation as described in Shi and Fan 2009 DOI: 10.1016/S1001-6058(08)60159-6

Note that there is a typo in Shi and Fan 2009 matrix Eq.16 should be +fp in the exponentials

note that phase speed c is considered positive so that U sign should be

defined with c direction as a reference

Computation will not work for critical or spupercritical condition (U

overocomes c at any depth)