Skip to content
/ Topo Public

NCAR Global Model Topography Generation Software for Unstructured Grids

Notifications You must be signed in to change notification settings

NCAR/Topo

Repository files navigation

February 2023, NCAR.

User's guide: https://github.com/NCAR/Topo/wiki/User's-Guide

What's new in version 2.0.1:

	*Command-line execution (e.g.):

	./cube_to_target --grid_descriptor_file ne30pg3.nc  
			 --intermediate_cs_name gmted2010_modis_bedmachine-ncube3000-220518.nc 
  	                 --output_grid ne30pg3 --smoothing_scale 100.0 
			 --name_email_of_creator 'Peter Hjort Lauritzen, [email protected]'

  	 Note: if you get the error message
	
	  No smoothed topo file specified
 	  Required argument not specified: 
 	  grid_descriptor_file

	 you are probably using Intel compiler. Please use GNU as outlined in the User's guide.

	*New improved source topography data (ice sheet regions)
	 See #10

	*Internal iterative Laplacian smoother with "no leak" option
	 See #39

	*Support for SCRIP and ESMF grid descriptor file formats

	*Seamless support for variable resolution grids 
	 (sub-grid-scale variables and smoothing seamlessly adapts to resolution changes)

	*CESM compliant metadata on netCDF file

Please note important bug fix in tag NCAR_Topo_2_0_1

This software is partially documented in

	Peter H. Lauritzen, Julio T. Bacmeister, Patrick Callaghan and Mark A. Taylor, 2015: 
	NCAR Global Model Topography Generation Software for Unstructured Grids. 
	Geosci. Model Dev., 8, 3975-3986, doi:10.5194/gmd-8-3975-2015

and updated by Julio Bacmeister/Peter Hjort Lauritzen for CESM2.2 support (internal smoothing, 
ridge finding algorithm, etc.) and variable resolution (Adam Herrington, Rene Wijngaard).


Overview of directories
=======================


bin_to_cube:
------------

Bin high resolution elevation data (on regular lat-lon grid) onto cubed-sphere grid.
Creates intermediate cubed-sphere data for cube_to_target. This is used to separate
scales for SGH and SGH30.

Note: The user does not need bin_to_cube step unless wanting to change
      source dataset and/or intermediate cubed-sphere resolution.


cube_to_target:
---------------

Code to process elevation data and remap to target grid.

List namelist options: Execute ./cube_to_target --help

Software will produce plot.sh which can be used to produce NCL plots of topography data
(source plot.sh)

Default interemdiate cubed-sphere data on Cheyenne is located at

	/glade/p/cgd/amp/pel/topo/cubedata/gmted2010_modis_bedmachine-ncube3000-220518.nc

Example:

See cubed_to_target/ne30pg3.sh. Execute (on Cheyenne) with:

    qcmd -l walltime=04:00:00 -- source ne30pg3.sh

Fast regression tests:

    source regr_test1.sh     -fast version of ne30pg3.sh but using ncube=540 
    	   		      intermediate cubed-sphere grid data
    source regr_test2.sh     -low resolution variable resolution test using ncube=540 
    	   		      intermediate cubed-sphere grid data
    source regr_test2_lap.sh -same as regr_test2.sh but using Laplacian smoother
    source regr_test3.sh      low resolution test for lat-lon grid using ncube=540 
    	   		      intermediate cubed-sphere grid data


regression-test-data:
---------------------

Data used for regression tests in cubed_to_target. See above.

make_rll_grid_descriptor_file:
------------------------------

Code to make SCRIP grid descriptor files for regular latitude-longitude grids