matlab_class/gcmfaces_calc/calc_overturn.m

function [FLD]=calc_overturn(fldU,fldV);
%object:    compute meridional overturning streamfunction
%inputs:    fldU and fldV are the fields of grid point transport
%output:    FLD is the streamfunction
%
%notes:     mygrid.LATS_MASKS is the set of quasi longitudinal lines along which
%               transports will integrated, as computed in gcmfaces_lines_zonal

global mygrid;

%initialize output:
n3=max(size(fldU.f1,3),1); n4=max(size(fldV.f1,4),1);
FLD=NaN*squeeze(zeros(length(mygrid.LATS_MASKS),n3+1,n4));

%prepare fldU/fldV:
fldU(isnan(fldU))=0; fldV(isnan(fldV))=0;

dxg=mk3D(mygrid.DXG,fldU); dyg=mk3D(mygrid.DYG,fldU); drf=mk3D(mygrid.DRF,fldU);
for k4=1:n4;
fldU(:,:,:,k4)=fldU(:,:,:,k4).*dyg.*drf*1e-6;
fldV(:,:,:,k4)=fldV(:,:,:,k4).*dxg.*drf*1e-6;
end;

%use array format to speed up computation below:
fldU=convert2array(fldU); fldV=convert2array(fldV);

for iy=1:length(mygrid.LATS_MASKS); 

   %get list ofpoints that form a zonal band:
   mskW=mygrid.LATS_MASKS(iy).mskWedge;
   vecW=gcmfaces_subset(mskW,fldU);
   mskS=mygrid.LATS_MASKS(iy).mskSedge;
   vecS=gcmfaces_subset(mskS,fldV);
   trsp=sum(vecW,1)+sum(vecS,1);

   %store:
   FLD(iy,1:n3,:)=-flipdim(cumsum(flipdim(trsp,2),2),2);

end; 

FLD(:,end,:)=0;


1	gforget	1.3	function [FLD]=calc_overturn(fldU,fldV);
2	gforget	1.2	%object: compute meridional overturning streamfunction
3			%inputs: fldU and fldV are the fields of grid point transport
4			%output: FLD is the streamfunction
5	gforget	1.3	%
6			%notes: mygrid.LATS_MASKS is the set of quasi longitudinal lines along which
7			% transports will integrated, as computed in gcmfaces_lines_zonal
8	gforget	1.1
9			global mygrid;
10
11			%initialize output:
12			n3=max(size(fldU.f1,3),1); n4=max(size(fldV.f1,4),1);
13	gforget	1.3	FLD=NaN*squeeze(zeros(length(mygrid.LATS_MASKS),n3+1,n4));
14	gforget	1.1
15			%prepare fldU/fldV:
16			fldU(isnan(fldU))=0; fldV(isnan(fldV))=0;
17
18			dxg=mk3D(mygrid.DXG,fldU); dyg=mk3D(mygrid.DYG,fldU); drf=mk3D(mygrid.DRF,fldU);
19			for k4=1:n4;
20	gforget	1.4	fldU(:,:,:,k4)=fldU(:,:,:,k4).dyg.drf*1e-6;
21			fldV(:,:,:,k4)=fldV(:,:,:,k4).dxg.drf*1e-6;
22	gforget	1.1	end;
23
24			%use array format to speed up computation below:
25			fldU=convert2array(fldU); fldV=convert2array(fldV);
26
27	gforget	1.3	for iy=1:length(mygrid.LATS_MASKS);
28	gforget	1.1
29			%get list ofpoints that form a zonal band:
30	gforget	1.5	mskW=mygrid.LATS_MASKS(iy).mskWedge;
31			vecW=gcmfaces_subset(mskW,fldU);
32			mskS=mygrid.LATS_MASKS(iy).mskSedge;
33			vecS=gcmfaces_subset(mskS,fldV);
34			trsp=sum(vecW,1)+sum(vecS,1);
35	gforget	1.1
36			%store:
37	gforget	1.5	FLD(iy,1:n3,:)=-flipdim(cumsum(flipdim(trsp,2),2),2);
38	gforget	1.1
39			end;
40
41			FLD(:,end,:)=0;
42
43