Tour of NCL Website www.ncl.ucar.edu Modified by R. Grotjahn 2016 03 04

NCL capabilities: Functions Support Visualization (many graphics, map overlays, 3-D, etc.) Mathematical (divergence, regridding, EOFs, filtering, etc.) Statistical (correlation, spectra, wavelets, kmeans, etc.) Earth-science specific (omega, vorticity, PV, crop variables, heat stress, Taylor diagram, etc.) Computational (array creation, file conversion, etc.) Support Examples (very many, illustrative, very useful guides) Reference listings of functions Manuals, training exercises, and presentations FAQs (searchable)

NCL capabilities: See overview: Handles many output formats http://www.ncl.ucar.edu/overview.shtml Handles many output formats publication-ready plots built-in capabilities, especially for earth science (>600 functions) supports Fortran and C externals

NCL routines: use specifically with climate and model data computing empirical orthogonal functions, Fourier coefficients, singular value decomposition, averages, standard deviations, sin, cosine, log, min, max, etc. retrieving and converting date information drawing primitives (lines, filled areas, and markers), wind barbs, weather map symbols, isosurfaces, and other graphical objects robust file handling 1-dimensional, 2-dimensional, and 3-dimensional interpolation, approximation, and regridding facilitating computer analysis of scalar and vector global geophysical quantities (most are based on the package known as Spherepack) retrieving environment variables and executing system commands

NCL capabilities: It can do a lot because it is built on many long-established libraries both graphical and mathematical

NCL Examples: Applications page www.ncl.ucar.edu/Applications/ Great starting place to find the capability you seek. Many datasets available as well

NCL Examples: Applications page links: Graphics Data Analysis (cont.) Applications page links: Graphics Cylindrical equidistant maps http://www.ncl.ucar.edu/Applications/cylineq.shtml Panel plots http://www.ncl.ucar.edu/Applications/panel.shtml WRF model http://www.ncl.ucar.edu/Applications/wrf.shtml Vectors http://www.ncl.ucar.edu/Applications/vector.shtml

NCL Examples: Applications page links: Datasets File I/O http://www.ncl.ucar.edu/Applications/list_io.shtml Shape files http://www.ncl.ucar.edu/Applications/shapefiles.shtml Topography http://www.ncl.ucar.edu/Applications/topo.shtml Daymet http://www.ncl.ucar.edu/Applications/daymet.shtml PRISM http://www.ncl.ucar.edu/Applications/prism.shtml

NCL FAQs: Link: http://www.ncl.ucar.edu/FAQ/ Useful learning tool, search it if you cannot find an example that does what you want to do Code snippets provided Categorized, but search is usually more effective You can ask your own questions.

NCL Functions: Functions are listed several ways: Also: alphabetically: http://www.ncl.ucar.edu/Document/Functions/list_alpha.shtml by category grouping: http://www.ncl.ucar.edu/Document/Functions/ by function type grouping: http://www.ncl.ucar.edu/Document/Functions/list_type.shtml via applications examples: http://www.ncl.ucar.edu/Applications/ Also: Graphics resources (like ws, vc, cn, etc.): http://www.ncl.ucar.edu/Document/Graphics/Resources/ but these are specialized, many are beyond the level of this class

NCL color tables: Link: http://www.ncl.ucar.edu/Document/Graphics/color_tables.shtml Create your own http://www.ncl.ucar.edu/Document/Graphics/create_color_table.shtml Use named colors http://www.ncl.ucar.edu/Document/Graphics/named_colors.shtml Examples: (rainbow, +/-, etc.)

NCL Other Popular Links: See: http://www.ncl.ucar.edu/links.shtml Markers: http://www.ncl.ucar.edu/Document/Graphics/marker_styles.shtml Dashed/line patterns: http://www.ncl.ucar.edu/Document/Graphics/dash_patterns.shtml Font tables: http://www.ncl.ucar.edu/Document/Graphics/font_tables.shtml

NCL Other Tools: Main link: http://www.ncl.ucar.edu/Document/Tools/ Conversion between ncl and some other formats, notably GRIB#, HDF_, shapefiles: http://www.ncl.ucar.edu/Document/Tools/ncl_convert2nc.shtml Wrapper to include Fortran or C functions in your NCL program: http://www.ncl.ucar.edu/Document/Tools/WRAPIT.shtml graphics x-window viewer idt: http://www.ncl.ucar.edu/Document/Tools/idt.shtml Links to other tools such as: ImageMagick: for conversion between graphics types (e.g. ps  png) mpeg2encode: to create a mpeg from a multi-frame ps file

NCL in python: PyNGL and PyNIO modules PyNGL (Python interface to NCL’s graphics library) http://www.pyngl.ucar.edu/ PyNIO (Python interface to NCL’s file I/O capabilities) http://www.pyngl.ucar.edu/Nio.shtml Training via exercises: http://www.pyngl.ucar.edu/Training/Exercises/

NCL Support: Common error messages: http://www.ncl.ucar.edu/Document/Language/error_messages.shtml Main email support link: http://www.ncl.ucar.edu/Support/email_lists.shtml ncl-talk: http://mailman.ucar.edu/mailman/listinfo/ncl-talk other pages for ncl installation questions about PyNGL and PyNIO http://mailman.ucar.edu/mailman/listinfo/pyngl-talk

NCL Tutorials: General link: http://www.ncl.ucar.edu/Training/Workshops/links.shtml NCAR Powerpoints: http://www.ncl.ucar.edu/Training/Workshops/Scripts/ Example scripts (contouring, maps, overlays, vectors, shapefiles,…): http://www.ncl.ucar.edu/Training/Workshops/Scripts/ Step-by-step Graphical exercises: http://www.ncl.ucar.edu/Training/Workshops/Exercises/ Sample data files: http://www.ncl.ucar.edu/Applications/Data/

NCL End of overview: Next: NCL-04_Shea-Brownrigg_Introduction.pdf Learn the basics of the language, make example plots.