Note: This page is PRELIMINARY. Steps described here may not work and/or there may soon be better ways to do these things.
These instructions were originally written by Oksana Guba and posted at https://docs.google.com/document/d/1ymlTgKz2SIvveRS72roKvNHN6a79B4TLOGrypPjRvg0/edit?usp=sharing . The basic idea is to create a .png file of the grid you want, then to use Paul Ullrich's SQuadGen code to turn it into the needed file type. For an overview of SQuadGen, see https://climate.ucdavis.edu/squadgen.php.
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