GIS on Macs

Until fairly recently, you couldn’t really put Macintosh and GIS in the same sentence without a sense of embarassment. But now the combination of a substantial body of mostly free software, plus the ability to run Windows for the market-dominating commercial products from ESRI, MapInfo, etc., makes a Mac a fabulous platform for GIS, remote sensing, cartography and scientific visualization.

Some worthwhile free software for OS X

For the command-line

The Unix side of the Mac has some valuable programs (you really should have at least the first two):

These, and more, are available through the fink project and MacPorts, admirable efforts which try to simplify the installation of Unix-based software for the less-geeky user. In large part they succeed; but the sacrifice one makes in using them is that they often lag behind current versions.

Probably the most important single site for Mac GIS software is William Kyngesburye’s kyngchaos website. In addition to valuable information on how to compile software on OS X, he offers reasonably up-to-date binaries of many programs, including grass, PostgresSQL, gdal and proj (note that qgis is now handled by Thank you, Mr Kyngesburye.


If you are running Windows on a Mac, several of the above are available for Windows; in addition you should look at Windows-only free software such as:

Not worth the trouble?

If you are taking GIS classes at high school or university then you will probably want to use the same software selected by your school. MultiSpec can do much of the classification and other raster analysis that the big boys can do, but if you have assignments, chances are that your graders will be looking for the numbers produced by the official software—those produced by MultiSpec may be just as valid, but they may be slightly different, and a grad student poring over a hundred assignments will be reluctant to listen to your explanation of why your answers are a bit unusual. But for learning the intricacies of remote sensing, or producing an analysis which does not have to match ‘the’ answer, free software can do much of what commercial products can. And approaching assignments via different software can help you to really understand both the problem and the answers.

Hints on data

As you collect more and more data for your GIS and remote sensing explorations, you will experience a common problem: organisation. Many gigabytes, many regions, many data formats and many projections will lead to many confusions if you don’t watch out. Some suggestions:


Some important general sites:

For those especially interested in elevation data and visualization, these three sites are superb:

And here are some major global data sites:


If you have any comments, please send e-mail to: geog  at-sign  oh-no-not-again  dot  info.