I was recently appointed the geography subject librarian for my library, which was mildly terrifying considering that I do not have a background in geography. But I was assigned the subject because of my interest in data visualization, and since my appointment I’ve learned a few things about the awesome potential opportunities to integrate Geographic Information Systems (GIS) and geospatial visualization tools into information literacy instruction and library services generally. A little bit of knowledge about GIS and geospatial visualization goes a long way, and is useful across a variety of disciplines, including social sciences, business, humanities and environmental studies and sciences. If you are into open data (who isn’t?) and you like maps and / or data visualization (who doesn’t?!) then it’s definitely worth it to learn about some tools and resources to work with geospatial information.
About GIS and Geospatial Data
Geographic Information Systems, or GIS, are software tools that enable visualizing and interpreting data (social, demographic, economic, political, topographic, spatial, natural resources, etc.) using maps and geospatial data. Often data is visualized using layers, where a base map (containing, for example, a political map of a city) or tiles are overlaid with shapes, data points, or choropleth shading. For example, in the map below, a map of districts in Tokyo is overlaid with data points representing the number of seniors living in the area: 1
You may be familiar with Google Earth, which has a lot of features similar to a GIS (but is arguably not really a GIS, due to its lack of data analysis and query tools typically found in a fully-featured GIS). You can download a free Pro version of Google Earth that enables you to import GIS data. GIS data can appear in a variety of formats, and while there isn’t space here to go into each of them, a few common formats you might come across include Shapefiles, KML, and GeoJSON. 2 Shapefiles, as the name suggests, represent shapes (e.g., polygons) as layers of vector data that can be visualized in GIS programs and Google Earth Pro. You may also come across KML files (Keyhole Markup Language), which is an XML-style standard for representing geographic data, and is commonly used with Google Earth and Google Maps. GeoJSON is another format for representing geospatial information that is ideal for use with web services. The various formats of GIS and geospatial data deserve a full post on their own, and I plan to write a follow-up post exploring some of these formats and how they are used in greater detail.
GIS/Geospatial Visualization Tools
ArcGIS is arguably the industry standard for GIS software, and the maker of ArcGIS (ESRI) publishes manuals and guides for GIS students and practitioners. There are a few different ArcGIS products: ArcGIS for Desktop, ArcGIS Online, and ArcGIS server. Personally I am only familiar with ArcGIS online, but you can do some pretty cool things with a totally free account, like create this map of where drones can and cannot fly in the United States: 3
ArcGIS can be very powerful and is particularly useful for complex geospatial datasets and visualizations (particularly visualizations that might require multiple layers of data or topographic / geologic data). A note about signing up with ArcGIS online: You don’t actually need to sign up for a ‘free trial’ to explore the software – you can just create a free account that, as I understand it, is not limited to a trial period. Not all features may be available in the completely free account.
CartoDB is both an open source application and a freemium cloud service that can be used to make some pretty amazing geospatial visualizations that can be embedded in web pages, like this choropleth that visualizes the amount of various kinds of pollution across Los Angeles.4
- OpenLayers – OpenLayers enables pulling in ’tile’ layers as base maps from a variety of sources, as well as enabling parsing of vector data in a wide range of formats, such as GeoJSON and KML.
- Leaflet.js – A fairly user-friendly and lightweight library used for creating basic interactive, mobile-friendly maps. In my opinion, Leaflet is a good library to get started with if you’re just jumping in to geospatial visualization.
Open Geospatial Data
Librarians wanting to integrate geospatial data visualization and GIS into interdisciplinary instruction can take advantage of open data sets that are increasingly available online. Sui (2014) notes that increasingly large data sets are being released freely and openly on the web, which is an exciting trend for GIS and open data enthusiasts. However, Sui also notes that the mere fact that data is legally released and made accessible “does not necessarily mean that data is usable (unless one has the technical expertise); thus they are not actually used at all.”6 Libraries could play a crucial role in helping users understand and interpret public data by integrating data visualization into information literacy instruction.
Some popular places to find open data that could be used in geospatial visualiation include:
- Data.gov – Since 2009, Data.gov has published thousands of public open datasets, including datasets containing geographic and geospatial information. As of this month, you can now open geospatial data files directly in CartoDB (requires a CartoDB account) to start making visualizations. There isn’t a huge amount of geospatial data available currently, but Data.gov will hopefully benefit from initiatives like Project Open Data, which was launched in 2013 by the White House and designed to accelerate the publishing of open data sets by government agencies.
- Google Public Data Explorer – This is a somewhat small set of public data that Google has gathered from other open data repositories (such as Eurostat) that can be directly visualized using Google charting tools. For example, you could create a visualization of European population change by country using data available through the Public Data Explorer. While the currently available data is pretty limited, Google has prepared a kind of open data metadata standard (Data Set Publishing Language, or DSPL) that might increase the availability of data through the explorer if the standard takes off.
- publicdata.eu – The destination for Europe’s public open data, a nice feature of publicdata.eu is the ability to filter down to datasets that contain Shapefiles (.shp files) that can be directly imported into GIS software or Google Earth Pro.
GIS and Geospatial Visualization In the Library
I feel like I’ve only really scratched the surface with the possibilities for libraries to get involved with GIS and geospatial data. Libraries are doing really exciting things with these technologies, whether it’s creating new ways of interacting with historical maps, lending GPS units, curating and preserving geospatial data, exploring geospatial linked data possibilities with GeoSPARQL or integrating GIS or geospatial visualization into information literacy / instruction programs. For more ideas about integrating GIS and geospatial visualization into library instruction and services, check out these guides:
- Introduction to Data Visualization, Angela Zoss, Duke University
- Mapping Tools, Laurie Allen, Bryn Mawr
- Geographic Information Systems (GIS), MIT
- GIS Services, Gregory McKinney, Temple University
- Geographic Information Systems (GIS), Washington University St. Louis
(EDIT 4/13) Also be sure to check out ALA’s Map and Geospatial Information Round Table (MAGIRT). Thanks to Paige Andrew and Kathy Weimer for pointing out this awesome resource in the comments.
If you’re working on something awesome related to geospatial data in your library and would be interested in writing about it for ACRL TechConnect, contact me on Twitter @lpmagnuson or drop me a line in the comments!
- AtlasPublisher. Tokyo Senior Population. https://www.arcgis.com/home/webmap/viewer.html?webmap=6990a8c5e87b42ee80701cf985383d5d. (Note: Apologies if you have trouble seeing or zooming in on embedded visualizations in this post; the interaction behavior of these embedded iframes can be a little unpredictable if your cursor gets near them. It’s definitely a drawback of embedding these interactive visualizations as iframes.) ↩
- The Open Geospatial Consortium is an organization that gathers and shares information about geographic and geospatial data formats, and details about a variety of geospatial file formats and standards can be found on its website: http://www.opengeospatial.org/. ↩
- ESRI. A Nation of Drones. http://story.maps.arcgis.com/apps/MapSeries/?appid=79798a56715c4df183448cc5b7e1b999 ↩
- Lauder, Thomas Suh (2014). Pollution Burdens. http://graphics.latimes.com/responsivemap-pollution-burdens/. ↩
- YMMV, but the performance of map animations that use Torque seems to be a little tricky, especially when embedded in an iFrame. I tried to embed the Ferguson Twitter map into this post (because it is really cool looking), and it really slowed down page loading, and the script seemed to get stuck at times. ↩
- Sui, Daniel. “Opportunities and Impediments for Open GIS.” Transactions in GIS, 18.1 (2014): 1-24. ↩