GIS (Geographic Information System) technology is an essential tool for any archaeologist; nobody would argue that. But in my experience as a scholar and also teaching introductory courses to GIS, I have realised that, in many occasions, archaeologists are not totally able to explain what a GIS is. This is caused in my opinion by something I call the tyranny of the technology. Let me explain.
Roger Tomlinson, the father of GIS, was the first person to use this terminology, in a paper published in 1968 entitled A Geographic Information System for Regional Planning. This work was the result of the development of the first true operational GIS, the Canada Geographic Information System in 1960, because, and this is the key factor, computers are essential for GIS.
A GIS is any system designed to capture, store, manipulate, analyse, manage, and present all types of spatial or geographical data. The development of computers in the second half of the 20th century, specially the “democratization” that started in the 80’s, made them an essential tool for any scholar. This, combined with the availability of high-resolution satellite images and the increased accuracy and affordability of hand-held GPS devices in the last two decades, has caused an uncontrolled increase on GIS studies.
First things first, this is a blog, not a scholar paper. It is a forum to debate and share ideas and experiences, not a publishable paper based on statistics of GIS use and misuse. But in my experience, GIS is many times misused in the scientific community because it has become very easy to use it. Is not that great? Indeed! There is no question that making technology accessible and affordable to everybody is fantastic. But too often I have encountered “GIS experts” whose only capabilities are opening GeoTiff files in a program. A map, any map, even the paper ones, is an ideal representation of a landscape. And it will be as good or bad as the person who made it, and this is not actually necessary related tothe resolution of the source files as much as with the capabilities and understanding of the mapper. And this creates a lot of noise, not only for the lack of expertise but also because many among these researchers never explain how they have made the map. So, before we start, remember this. A GIS paper always needs a clear methodology section that includes the version of the software and the map sources that were used. The magic word is Replicability.
So why all these disclaimers? Because I intend to publish here from time to time some posts about GIS methodology for beginners based on my research and teaching experience on the topic. I am preparing a more extensive and systematic publication on teaching GIS for non-specialists, and I think it is a great idea to test my methodology with whoever wants to try the advices I will give here. Despite being a basic course, it will cover a wide range of topics and types of analyses, and although you will not become a GIS expert, I am sure you will be able to prepare very good and reliable maps for your research and publications, including analyses of view-sheds, least cost paths and, my favourites, predictive models. I will leave .pdf of these lessons in my academia.edu account, so you will have a better edited version, in case you want to incorporate them to your research. Since the final publication will take a (long) while I suggest you to use this blog as on-line reference if you need to cite these notes in your work:
RODRIGUEZ-ALVAREZ, E. Introduction to GIS (I). Archaeostuff. Available at: (accessed date).
These notes are based on a seminar I taught for some semesters at University of Arizona, so I am very grateful to everybody who took part on them and helped me with their questions and encouragement to take this step further and try to convert my notes into a coherent guide. Obviously, these lessons are not a substitute for a University-level class. But I believe that self-training, if it is taken seriously and from reliable sources, it is not only possible but also a great improvement on our careers. So, let us start by having a look at two web pages that are going to become your best friends: GRASS, where we will finds the free software we are going to work with, and earthexplorer.usgs.gov, a fantastic source for free DEM maps from all over the world. Spend some time getting familiar with it while I prepare the next post on GIS. It will be ready as soon as possible!