>I downloaded ISCCP data (D2) from the Langley Center.
><http://eosweb.larc.nasa.gov/HBDOCS/langley_web_tool.html>The data are
>on a equal-area grid in hdf format. Does anynone have a NCL sccript to
>convert this dataset in netcdf format on a square grid (i.e. 2.5x2.5) or
>on a T42 grid ?
Yes.
However, the HDF formated files are not of the
HDF-SDS [Scientific Data Set] or HDF-EOS 'flavors'
which NCL currently is designed to read. Rather
they are 'VDATA'.
This requires that the appropriate libraries
be loaded via a shared object. If your local system
does not currently have HDF, it can be obtained from
http://hdf.ncsa.uiuc.edu/release4/obtain.html
The main steps in the process are:
(1) The NASA provided fortran code isccp_d2_read.f
must be made a subroutine. Then create a shared object via:
WRAPIT -d -L /usr/local/lib -l df -l mfhdf isccp_d2_read.hdf_ncl.f
(2) create an NCL script that loads the external shared object
external ISCCP "./isccp_d2_read.hdf_ncl.so"
(3) The user must preallocate space for all 130 variables
on a 72x144 grid.
nvar = 130
mlon = 144
nlat = 72
xmsg = -1000. ;same as NASA ISCCP
x = new( (/nvar,nlat,mlon/), "float", xmsg)
Please contact me directly for more details about reading the data.
--- good luck D_______________________________________________ ncl-talk mailing list ncl-talk@ucar.edu http://mailman.ucar.edu/mailman/listinfo/ncl-talk
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