27.2 Isopycne position in the course of autumn
Table of Contents
This page provides access to the Mediterranean seasonal isopycnal climatology reconstructed from the MODB data base. The resulting 3D fields (depth, salinity and temperature) are stored as 3D matrices, with description of the grid location. Direct access to these fields and a description of the file format are also provided on this page.
If there is any problem with this data set (reading, importing, ...) or for any comment please contact (A.Elmoussaoui@ulg.ac.be).(up to Table of Contents)
2. First experience
In this first time only one version of this seasonal isopycnal gridded data set is released (MED_ISOP1).(up to Table of Contents)
3. Isopycnal Analysed Data Fields
There are four seasons for the data set :
There are three files for each season :
Units are 'metre' for depth, 'psu' for salinity and 'degree Celsius' for temperature(up to Table of Contents)
4. Matrix description
To understand the way the data is stored, please refer to the figure below. The files are stored in a 3D array (matrix) with 3 indexes I, J, K, going from 1 to IMAX, 1 to JMAX, 1 to KMAX. The origin is located at the 'bottom left deepest corner'.
There are KMAX isopycnal surfaces from the bottom (K=1) to the surface (K=KMAX). Increasing I's go from W to E and increasing J's go from S to N.
Islands, coasts and places where there are no values are represented by an EXCLUSION VALUE.(up to Table of Contents)
The point (i,j,k) is located at (-5.5 + i*0.25 , i=1,167) long and (30.0 + j*0.25 , j=1,63) lat
at a isopycnal level given by the Kth line of the file (seasonal average density)
(up to Table of Contents)
6. Reading the data
The data sets are stored in compressed ASCII files. First you must 'uncompress' the files with the Unix command 'gunzip filename.gz'.
The first line of the ASCII file contains the dimension of the array : IMAX, JMAX, KMAX. The integers are stored with the FORTRAN format I5.
The second line contains the exclusion value, the minimum and the maximum value of this file. These numbers are stored with the FORTRAN format E12.5.
The remaining lines contains the data of the array, with 5 numbers per line (except the last line for each I-line).
The array is stored in horizontal slices from sea surface to sea bottom and from north to south. So the indexes go from :
read IMAX, JMAX, KMAX read VALEX, VALMIN, VALMAX DO K = KMAX to 1 DO J = JMAX to 1 DO I = 1 to IMAX read ENDDO ENDDO ENDDO(up to Table of Contents)
7. Access to the Data Fields
(up to Table of Contents)