[ferret_users] Mass transport normal to a vertical section along a track

[Praveen V K <veluthed@xxxxxxxxxxx>]

Hi All,

I am wondering whether ferret can do this.

I have a 3D-regular grid data of 240 X 240 X 24 (x,y,z) dimension.
Can we calculate the Mass transport normal to a Section line which is  
not parallel to Longitude or Latitude in ferret?

I tried the following method.

use uv.nc
 let vtrans = v*xbox*zbox
 let utrans = u*ybox*zbox

! Transport Section line (approximately diagonal to lat-lon grid)
let xpoints = {-42.2090,-41.7973,-41.3856}
let ypoints = {62.3584, 62.1288,61.8992}

let utrans_sec = samplexy(utrans,xpoints,ypoints)
let vtrans_sec = samplexy(vtrans,xpoints,ypoints)
let trans_mag  = (utrans_sec^2+vtrans_sec^2)^0.5
     let trans = trans_mag*vtrans_sec/abs(vtrans_sec) ! This is to  
get the direction, since I know they are going south.

I am not sure whether I am getting the transport normal to the section or not!
If not, can we get normal transport for such sections in ferret.

Thanks

Praveen