Spatial Mapping Goes Mainstream

What began as a high-tech tool for geologists and cartographers has now become a go-to method of analysis for medical researchers, climatologists, anthropologists, marine biologists—really anyone working with data and maps.

Fifteen scientists from Stanford and USGS converged at Stanford Wednesday afternoon to showcase the latest in GIS—Geographic Information Systems—including maps of salmon shark migrations, Oakland bike routes, and the flow of arsenic in the Mekong River Delta.

Jasper Van der Bruggen, a GIS assistanct at Stanford, said the popularity of Google Maps and Google Earth has led to widespread interest in GIS technology.

“Ten years ago there was only a small group of people using GIS,” he said. “What we’ve seen in the last decade and especially in the last couple of years is that the general public became much more spatially aware.”

What Van der Bruggen means by that phrase is that rather than relying on charts and graphs to visualize data, we’re increasingly using that data as layers on top of maps. This makes it far easier in many cases to spot positive correlations between variables.

Take the case of the salmon shark. Natalie Arnoldi, a Biology major at Stanford, has been on a team tagging salmon sharks throughout the waters off the Pacific Coast. Arnoldi and her team then tracking the movements of the sharks by mapping their movement using GIS.

Her team’s research has led to a number of important findings, including the odd discovery that all female salmon sharks live in the Eastern Pacific, while males live in the Western Pacific and juveniles in the middle.

The research has also pinpointed hotspots where salmon sharks feed: next to river mouths where salmon spawn.

These findings would have been far more difficult to come by using older methods of data visualization.

“GIS is a completely different way to visualize and analyze your data,” said Van der Bruggen. “You do it spatially. Sometimes there are correlations or trends that are not visible if you present it in a table or in a graph. You have to put it on a map, otherwise you will not see those trends happening.”

Stacie Wolny, a GIS analyst at Stanford’s Natural Capital Project, has been working with the Colombian government to predict the negative effects of mining on watersheds throughout the country.

Using a modeling system they developed called InVEST—a tool for “progressive decision-making”—Wolny was able to visually depict which watersheds in Colombia would be damaged under different mining scenarios. Her mapping found that if the government allowed all requested mining permits to move forward, many watersheds would be totally destroyed.

“We’re giving all this information to the Colombian government, and hopefully they’ll be able to make better decisions,” said Wolny.

Wednesday’s GIS Day coincides with similar events in 45 countries around the world during Geography Awareness Week.

Van der Bruggen says one particularly exciting development in the near future will come as thousands of scientists use GIS tools to build maps using US Census data, which has been trickling out this year. He says that it’s a treasure trove of information since it contains ethnicity, income, and other important variables.

In the meantime, Stanford’s GIS team—housed at Branner Library—will continue to offer free workshops for the rest of this week on GIS, as well as continuing support to researchers throughout the university.