G5NR Data Access Guide: Difference between revisions
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==== Programming ==== | ==== Programming ==== | ||
===== [[G5NR data access using C|C]] ===== | ===== [[G5NR data access using C|C]] ===== | ||
===== Fortran ===== | ===== Fortran ===== | ||
For reading a downloaded file or accessing directly via OPeNDAP using Fortran, please see [[G5NR data access using Fortran|this]] page. | For reading a downloaded file or accessing directly via OPeNDAP using Fortran, please see [[G5NR data access using Fortran|this]] page. | ||
===== Shmem example ===== | ===== Shmem example ===== | ||
==== Free clients ==== | ==== Free clients ==== | ||
Revision as of 10:55, 29 October 2014
For questions or comments please send an email to g5nr at lists dot nasa dot gov.
G5NR background
The GEOS-5 Nature Run (Ganymed release) is a 2-year global, non-hydrostatic mesoscale simulation for the period 2005-2006. In addition to standard meteorological parameters (wind, temperature, moisture, surface pressure), this simulation includes 15 aerosol tracers (dust, seasalt, sulfate, black and organic carbon), O3, CO and CO2. This model simulation is driven by prescribed sea-surface temperature and sea-ice, daily volcanic and biomass burning emissions, as well as high-resolution inventories of anthropogenic sources.
File format and organization
GEOS-5 files are generated with the Network Common Data Form (NetCDF-4) library, which uses Hierarchical Data Format Version 5 (HDF-5) as the underlying format. NetCDF-4 is an open-source product of UCAR/Unidata (https://www.unidata.ucar.edu/software/netcdf/) and HDF-5 is developed by the HDF Group (http://www.hdfgroup.org/). One convenient method of reading GEOS-5 files is to use the NetCDF-4 library, but the HDF-5 library can also be used directly. These files can be easily read by applications such as IDL, Matlab, GrADS, FERRET, NCL, Panoply as well in Python using the netCDF4, h5py or PyTables packages.
File naming conventions
Read file metadata
Download data files
Retrieve (global) data from FTP server
Retrieve data (global/subset) using download tool
Read downloaded data files
Fortran program to read data from downloaded file
Python program to read data from downloaded file
OPeNDAP client access
OPeNDAP is a data server architecture that allows users to use data files that are stored on remote computers with their favorite analysis and visualization tools. Opening an OPeNDAP file is as easy replacing the file name in the client software by an OPeNDAP URL. All G5NR collections that are provided by ftp/download-tool are also available on the OPeNDAP server
http://opendap.nccs.nasa.gov/dods/OSSE/GEOS-5.12/BETA9.