/[MITgcm]/MITgcm_contrib/gmaze_pv/compute_density.m
ViewVC logotype

Annotation of /MITgcm_contrib/gmaze_pv/compute_density.m

Parent Directory Parent Directory | Revision Log Revision Log | View Revision Graph Revision Graph


Revision 1.2 - (hide annotations) (download)
Mon Jul 10 15:09:01 2006 UTC (17 years, 10 months ago) by gmaze
Branch: MAIN
Changes since 1.1: +8 -1 lines
add PVflux diag and update

1 gmaze 1.1 %
2 gmaze 1.2 % [] = compute_density(SNAPSHOT)
3 gmaze 1.1 %
4     % For a time snapshot, this program computes the
5     % 3D density from potential temperature and salinity.
6     % THETA and SALTanom are supposed to be defined on the same
7     % domain and grid.
8     %
9 gmaze 1.2 % Files names are:
10     % INPUT:
11     % ./netcdf-files/<SNAPSHOT>/<netcdf_THETA>.<netcdf_domain>.<netcdf_suff>
12     % ./netcdf-files/<SNAPSHOT>/<netcdf_SALTanom>.<netcdf_domain>.<netcdf_suff>
13     % OUPUT:
14     % ./netcdf-files/<SNAPSHOT>/RHO.<netcdf_domain>.<netcdf_suff>
15     %
16 gmaze 1.1 % 06/21/2006
17     % gmaze@mit.edu
18     %
19    
20    
21     function compute_density(snapshot)
22    
23    
24     %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
25     %% Setup
26     %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
27     global sla netcdf_THETA netcdf_SALTanom netcdf_domain netcdf_suff
28     pv_checkpath
29    
30    
31     %% THETA and SALTanom files name:
32     filTHETA = strcat(netcdf_THETA ,'.',netcdf_domain);
33     filSALTa = strcat(netcdf_SALTanom,'.',netcdf_domain);
34    
35     %% Path and extension to find them:
36     pathname = strcat('netcdf-files',sla,snapshot);
37     ext = strcat('.',netcdf_suff);
38    
39     %% Load netcdf files:
40     ferfile = strcat(pathname,sla,filTHETA,ext);
41     ncTHETA = netcdf(ferfile,'nowrite');
42     THETAvariables = var(ncTHETA);
43    
44     ferfile = strcat(pathname,sla,filSALTa,ext);
45     ncSALTa = netcdf(ferfile,'nowrite');
46     SALTavariables = var(ncSALTa);
47    
48     %% Gridding:
49     % Don't care about the grid here !
50     % SALTanom and THETA are normaly defined on the same grid
51     % So we compute rho on it.
52    
53     %% Flags:
54     global toshow % Turn to 1 to follow the computing process
55    
56    
57     %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
58     %% Now we compute the density
59     %% The routine used is densjmd95.m
60     %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
61    
62     % Axis (usual netcdf files):
63     if toshow,disp('Dim');end
64     [lon lat dpt] = coordfromnc(ncTHETA);
65     nx = length(lon);
66     ny = length(lat);
67     nz = length(dpt);
68    
69     % Pre-allocate:
70     if toshow,disp('Pre-allocate');end
71     RHO = zeros(nz,ny,nx);
72    
73     % Then compute density RHO:
74     for iz = 1 : nz
75     if toshow,disp(strcat('Compute density at level:',num2str(iz),'/',num2str(nz)));end
76    
77     S = SALTavariables{4}(iz,:,:) + 35; % Move the anom to an absolute field
78     T = THETAvariables{4}(iz,:,:);
79     P = (0.09998*9.81*dpt(iz))*ones(ny,nx);
80     RHO(iz,:,:) = densjmd95(S,T,P);
81    
82     end %for iz
83    
84    
85    
86    
87     %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
88     %% Record output:
89     %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
90    
91     % General informations:
92     netfil = strcat('RHO','.',netcdf_domain,'.',netcdf_suff);
93     units = 'kg/m^3';
94     ncid = 'RHO';
95     longname = 'Density';
96     uniquename = 'density';
97    
98     % Open output file:
99     nc = netcdf(strcat(pathname,sla,netfil),'clobber');
100    
101     % Define axis:
102     nc('X') = nx;
103     nc('Y') = ny;
104     nc('Z') = nz;
105    
106     nc{'X'} = 'X';
107     nc{'Y'} = 'Y';
108     nc{'Z'} = 'Z';
109    
110     nc{'X'} = ncfloat('X');
111     nc{'X'}.uniquename = ncchar('X');
112     nc{'X'}.long_name = ncchar('longitude');
113     nc{'X'}.gridtype = nclong(0);
114     nc{'X'}.units = ncchar('degrees_east');
115     nc{'X'}(:) = lon;
116    
117     nc{'Y'} = ncfloat('Y');
118     nc{'Y'}.uniquename = ncchar('Y');
119     nc{'Y'}.long_name = ncchar('latitude');
120     nc{'Y'}.gridtype = nclong(0);
121     nc{'Y'}.units = ncchar('degrees_north');
122     nc{'Y'}(:) = lat;
123    
124     nc{'Z'} = ncfloat('Z');
125     nc{'Z'}.uniquename = ncchar('Z');
126     nc{'Z'}.long_name = ncchar('depth');
127     nc{'Z'}.gridtype = nclong(0);
128     nc{'Z'}.units = ncchar('m');
129     nc{'Z'}(:) = dpt;
130    
131     % And main field:
132     nc{ncid} = ncfloat('Z', 'Y', 'X');
133     nc{ncid}.units = ncchar(units);
134     nc{ncid}.missing_value = ncfloat(NaN);
135     nc{ncid}.FillValue_ = ncfloat(NaN);
136     nc{ncid}.longname = ncchar(longname);
137     nc{ncid}.uniquename = ncchar(uniquename);
138     nc{ncid}(:,:,:) = RHO;
139    
140     nc=close(nc);
141    

  ViewVC Help
Powered by ViewVC 1.1.22