The NOAA National Operational Model Archive and Distribution System (NOMADS) provides information on available services for use with NOMADS data, along with a listing of some useful tools.
NCEI Tools
NOAA's Weather and Climate Toolkit allows you to download and visualize data available from NCEI, to include climate and weather data, radar data, satellite data, and NOMADS model data. The tool may be downloaded as stand-alone software or run through a java interface.
External Tools
The tools listed below are freely available software that can be used with most NOMADS data. The list of tools is not all-inclusive. NCEI cannot guarantee the tools are free from viruses or could compromise the security of your computer system. The listing is not an endorsement for any particular organization and is provided for general informational purposes.
Utilities
Wgrib is a command-line program useful for working with GRIB-1 files. It provides you with the ability to inventory, decode, and rewrite GRIB-1 files.
Wgrib2 is another command-line tool that works with both GRIB-1 and GRIB-2 files. It has much more functionality than Wgrib.
CDO tools are a set of command-line tools for both manipulating data files and for analyzing their data. Both GRIB and NetCDF file formats are supported with over 600 functions available for processing data.
NetCDF Operators is another set of command-line tools that perform several operations on NetCDF files. GRIB data downloaded from NOMADS can be converted to NetCDF format and used with NCO tools to perform a variety of operations on the data. NOMADS' services also provide conversion of GRIB data to NetCDF format.
Viewers
Panoply is a Java application provided by NASA for plotting gridded data. It handles both GRIB and NetCDF file formats. Several types of plots can be made with Panoply: horizontal 2-D, vertical slices, time plots, and even 2-D arrays of values. Images can be saved and animations made. Various map projections and color scales can be chosen.
Ncview is a basic NetCDF file viewer. It was developed by David W. Pierce at the Scripps Institution of Oceanography, University of California, San Diego.
ncBrowse is a Java application provided by NOAA/PMEL/EPIC for plotting NetCDF files.
Data Analysis
The Grid Analysis and Display System (GrADS) is available through the Institute of Global Environment and Society (IGES), Center for Ocean-Land-Atmosphere Studies (COLA). GrADS is an advanced tool for visualizing both gridded and station data from several different file formats, including GRIB, NetCDF, and BUFR. Several types of plots can be made with GrADS: contours, shaded contours, streamlines, barb plots, vector plots, line graphs, bar graphs, and station plots. GrADS may be used interactively or through pre-programmed scripts.
Ferret is a program useful for the analysis and visualization of gridded data. Designed for oceanographers and meteorologists, it is capable of utilizing OPeNDAP to retrieve data from NOMADS and other remote sites that provide OPeNDAP services.
The University Corporation for Atmospheric Research (UCAR) Computational & Information Systems Lab (CISL) program offers the National Center for Atmospheric Research (NCAR) Command Language (NCL). NCL is a program for analyzing and visualizing scientific data. NCL is an interpreted language suitable for making scripts. NCL handles many file formats, including GRIB and NetCDF.
The Integrated Data Viewer (IDV) is a Java-based set of libraries and applications for visualizing and analyzing various types of geophysical data. IDV was developed by the Unidata Program Center (UPC), University Corporation for Atmospheric Research (UCAR). IDV will render 3-D plots of data and allow you to interactively generate plots and animations.
The Man computer Interactive Data Access System (McIDAS) is another Java-based package of tools for analyzing and displaying geophysical data in two or three dimensions. Maintained by the Space Science and Engineering Center (SSEC) of the University of Wisconsin-Madison, McIDAS includes tools for handling various data types, including gridded GRIB and NetCDF data.
VAPOR is an advanced set of applications and libraries for visualizing gridded data. It enables you to render 3-D volumes, isosurfaces, contours, flow lines, and many other types of plots. Tools are included with VAPOR to convert GRIB, NetCDF, and other file formats into its own native VAPOR Data Collection (VDC) format.
Lawrence Livermore National Laboratory (LLNL) leads a consortium in the development of an open source collection of scientific data analysis and visualization utilities known as UV-CDAT. The utilities work with a variety of data types and are designed to work with the Earth System Grid Federation (ESGF).
Libraries
The European Centre for Medium-Range Weather Forecasts (ECMWF) produces an application program interface (API) library for working with GRIB1 and GRIB2 files. The library can be used to develop software to encode, decode, and manipulate GRIB files. The library also comes with some command-line tools ready for compiling and using on GRIB files.
The University Corporation for Atmospheric Research (UCAR) Unidata program maintains a set of C, C++, and FORTRAN libraries for working with NetCDF files.
NOMADS Access Services
The following services are available for retrieving, viewing, and processing NOMADS data at NCEI.
THREDDS Data Server (TDS) is a web server available through NCEI NOMADS for a variety of methods to search, obtain information on, and download data. TDS provides services through OPeNDAP protocol, ncWMS, Web Coverage Services, ncISO, and NetCDF subset services. NOMADS datasets can be received through TDS by selecting TDS access links through the NOMADS data products pages or by navigating through the NOMADS' TDS catalog. The same model data is now available on the new NCEI Center-Wide TDS.
File Transfer Protocol (FTP)
File Transfer Protocol (FTP) is a standard network protocol provided by NCEI and NOMADS for downloading data files. NOMADS datasets can be received through the FTP service by selecting FTP access links through the NOMADS data products pages or by navigating through the NOMADS FTP directory structure.
Hypertext Transfer Protocol Secure (HTTPS)
HTTPS provides another standard network protocol to retrieve data files from NOMADS. HTTPS services are available by selecting HTTPS access links through the NOMADS data products pages or by navigating through the NOMADS' HTTPS directory structure.
The NCEI Archive Information Request System, formerly known as the HDSS Access System (HAS), allows access to data stored on the Hierarchical Data Storage System (HDSS) tape robotics storage system. Model data not available online might be available offline though AIRS by selecting AIRS or HAS access links through the NOMADS data products pages or by navigating through the "Model" data section of the AIRS System.
ERDDAP is another data server that gives you the means to subset gridded model data in several common file formats and to visualize data by making graphs and maps. Access to selected model, satellite, and climate data is available via the NCEI ERDDAP.
