NetCDF

Status Report: September 2012 - April 2013

Russ Rew, Dennis Heimbigner, Ward Fisher

Strategic Focus Areas

The netCDF group's activities support Unidata's strategic goals in the following ways:

  1. Enable widespread, efficient access to geoscience data
    by developing netCDF and related cyberinfrastructure solutions to facilitate local and remote access to scientific data.
  2. Develop and provide open-source tools for effective use of geoscience data
    by supporting the use of netCDF and related technologies for analyzing, integrating, and visualizing multidimensional geoscience data; enabling visualization and effective use of very large data sets; and accessing, managing, and sharing collections of heterogeneous data from diverse sources.
  3. Provide cyberinfrastructure leadership in data discovery, access, and use
    by developing useful data models, frameworks, and protocols for geoscience data; advancing geoscience data and metadata standards and conventions; and providing information and guidance on emerging cyberinfrastructure trends and technologies.
  4. Build, support, and advocate for the diverse geoscience community
    by providing expertise in implementing effective data management, conducting annual training workshops, responding to support questions, maintaining comprehensive documentation, maintaining example programs and files, and keeping online FAQs, best practices, and web site up to date; fostering interactions between community members; and presenting community perspectives at scientific meetings, conferences, and other venues.

Activities Since the Last Status Report

Project and Issue Tracking

We use a project tracker tool to manage bug reports, track issues, plan releases, and make our development process more transparent to users. Between September 2012 and April 2013, we created 51 issues, updated 83 issues, resolved 30 issues, and we currently have 86 open issues. (Note: issues vary greatly in size and effort required to resolve, so number of issues is not a useful measure of amount of work to do.)

Workshops

We conducted annual netCDF training workshops in October, 2012. There were 26 registrants for the "NetCDF for New Users" session, and 17 registrants for the "NetCDF Annual Update" session. The 2012 workshops were put online in early November.

Releases

Several release candidates were made available in early 2013, leading up to Version 4.3.0 release of netCDF-C software in April. This release includes important portability and performance enhancements, bug fixes, and new features, as described in the Release Notes.

Release 4.3.0 is the first to include portability to the Windows Visual Studio development environment, using CMake, a new alternative to previous autoconf-based distributions, which are still supported.

The Windows porting work has significantly improved netCDF interoperability and led to fewer requests for support for help building netCDF from source on Windows platforms, now that pre-built libraries and executables for the latest version are available.

Conference Presentations, Blogs, and Publications

Steve Sullivan produced a white paper on improving netCDF compression, to accompany prototype software. At the AMS Austin meeting in January, Russ Rew presented a talk on improving data accessibility by chunking large datasets, updated in April for the UCAR 2013 Software Engineering Assembly Conference, and the subject of Unidata Developer's Blogs.

Standards

In February, the Open Geospatial Consortium adopted the Climate and Forecast (CF) extension to the existing OGC Network Common Data Form (NetCDF) Core Encoding Standard version 1.0.


Planned Activities

Ongoing Activities

  • Respond to support questions and help requests from netCDF users.
  • Improve support for netCDF on various platforms.
  • Incorporate successful features of netCDF-Java into C-based libraries.
  • Respond to needs of a growing user community for representing observational data, satellite products, and geoinformatics data.

New Activities

During the next six months, we plan to create and present a new netCDF workshop for developers, expand Windows support to include the Fortran library, improve the documentation generated by Doxygen, and release updated versions of netCDF-Fortran and netCDF-C++ packages.

Metrics

During the last year, there were 98,000 downloads from 124 countries of the C-based netCDF software from Unidata, in addition to downloads from mirror sites, package management systems, and incorporation into other software packages. Detailed metrics, including for netCDF-Java/CDM, are available.

Other metrics include number of

  • Google hits for "netcdf": 1,270,000
  • Google hits for "netcdf-3": 763,000
  • Google hits for "netcdf-4": 715,000
  • Bing hits for "netcdf": 231,000
  • blog mentions of netCDF: 19,600
  • videos tagged as netCDF-relevant: 32,200
  • Google scholar entries for "netcdf": 9,320
  • books containing the term "netcdf": 6,620
  • free software packages that can access netCDF data: at least 84
  • U.S. patents mentioning netCDF: 51
  • commercial software packages that can access netCDF data: at least 21
  • Coverity estimate, defects per thousand lines of code: 1.469