GIS and Scale

I’m giving two papers at EAAs. The first, I’ve toiled with for a few months. The other paper is like a benign parasite that’s been hanging around in the back of my head for just as long but has wiggled its way to the surface. The paper is in a lightening session organized by Becky Seifried and Tuna Kalayci with allows for 6 minute papers with 6 slides. I’m thinking that at about 100-120 words per minute, my paper should be around 600-700 words. Here’s my first shot at putting words on the screen.

GIS and Scale

For as long as I can remember, I’ve been fascinated by Jorge Luis Borges one-paragraph story, “On Exactitude in Science.” It tells the well-knowns story of Cartographers Guild who produced a map of the Empire at the scale of 1:1. The map, of course, was useless, but “still today, there are Tattered Ruins of that Map, inhabited by Animals and Beggars.”

I never think of this map more than when wandering the Greek countryside having studied a trusty 1:5000 map, only to discover that a seemingly manageable slope disguised a 3 meter cliff nestled between two sections of otherwise gentle incline. 

Archaeology, of course, has long concerned itself with scale and the resolution of the tools that we use to produce the images, measurements, and figures through which we develop our arguments for life in the past. Depending on the purpose, a 1945 air photo or Corona satellite image, for example, maybe nearly unusable or a brilliant window into a past landscape, or both. As a archaeologist concerned primarily with regional scale survey, I tend to find frequently parallels between the scale of maps, aerial and satellite photographs, and my own work. It should hardly surprise anyone that a way of  seeing the landscape the developed, in part, from the field of Area Studies should be so comfortable using the tool designed to allow “seeing like a state.” Millimeters and centimeters rarely concern us much when our study area is measured in tens of square kilometers and survey units measured in thousands of square meters.

Excavators deal with issues of scale as well. While strata are empirical entities, excavators rely upon an often unacknowledged level of resolution in discerning which divisions in strata represent meaningful cultural or natural phenomenon. As microstratigraphic analyses have increasingly revealed, with increases to stratigraphic resolution, new information becomes visible. The widespread use of petrography and microscopic analysis of ceramics has similarly challenged longstanding practices of ceramic identification based on typologies, shapes, and macroscopic definition of fabrics. It is perhaps unsurprisingly that scale in time and scale in space are often related in archaeological practice with every day life of a small holder or peasant or the intermittent activity of a seasonal settlement requiring much finer resolution than the life on an region or an Empire. (This is a point more eloquently made by Borges in his story.)

At the same time, as archaeologists we are increasingly aware of impact of processes that take place on a global scale, including climate change, we are also being challenged to expand the scale of our understanding beyond even the most expansive regional survey project. The scope of climate patterns alone can easily exceed even continental scale shifting the inconvenience of 1:5000 meter maps from lacking human sized detail to being too detailed than necessary for analysis.  

As Ömür Harmanşah has pointed, however, the archaeology of the Anthropocene will require a more nimble archaeology that can move between spatial scales to integrate the daily life of communities and, even, individuals with expansive global patterns. This spatial scaling likewise requires chronological scaling which allows us to slow down and accelerate from seasons to centuries. In recent years, archaeologists and historians have celebrated our ability to aggregate and analyze BIG DATA and the growing ubiquity of GIS, remote sensing on a large scale, and various linked data standards has expanded our tool kit for integrating big data. At the same time, archaeology never tires of refining chronologies and producing ever more chronologically granular data that ranges from seasonal shifts to the ephemeral of individual experience. 

The question that remains is how do we manage these vast shifts in scale when the lure of BIG DATA and the powerful tools created to manage vast flows of information receive constant refinement and the practices required to wrest the fine grain information necessary to understand small scale experience remain time consuming, idiosyncratic, and highly particularistic?