Map data from USGS DEM and NLCD 2006. Original map produced by Carl Sack, 2012 (CC-BY-SA).

Welcome to my website. A little bit about me: I make maps. I teach. I enjoy being in nature, exploring new places, and building community. I like to eat good food and read good books that make me think. I am a strongly-motivated justice seeker looking for ways that mapping can empower the marginalized and oppressed in society. I am a proud new father. Of my many useful skills and likeable attributes, I believe the most important is that I am a life-long learner, which entails a constant search for new knowledge and skills and teaching others what I know.

"In every outthrust headland, in every curving beach, in every grain of sand there is the story of the earth."

-Rachel Carson

All work on this page is authored by Carl Sack and licensed Creative Commons (CC-BY-SA).

Invisible Nation: Mapping Sioux Treaty Boundaries: This was a series of maps I put together showing the boundaries of Sioux Territory as defined by the peace treaties of 1851 and 1868 and interpreted by the Indian Claims Commission in the 1960s and 70s. These maps involved experimenting with adding sattelite imagery to shaded relief. I detail my research process and design choices in this blog post.

The Black Snake in Sioux Country: I made this map to show the geography of the 2016 struggle of the Standing Rock Sioux Tribe and their allies against the Dakota Access Oil Pipeline in North Dakota. The map highlights the reroute of the pipeline corridor to avoid potential water contamination in majority-white communities while putting Native American communities at greater risk, along with the locations of resistance camps and where the pipeline company preemptively bulldozed an area containing archaeological sites to avoid a court-ordered halt to construction. My full statement on the map is available here.

Rivers At Risk: This is a series of maps I started work on to show the location of each segment of Enbridge Energy's Line 61 and Line 5 pipelines and the rivers they cross that would be threatened by an oil spill. Enbridge's Line 61 is in the process of expansion up to 1.2 million barrels per day of tar sands oil, 150% of the capacity of the more famous (and failed) KeystoneXL pipeline. Enbridge is considering constructing a "twin" to Line 61 that would carry an additional 450,000 barrels per day.

Maps for Capitalism, Nature, Socialism: I create about one map every two months pertaining to an environmental justice issue on contract for the peer-reviewed journal Capitalism, Nature, Socialism.

A Sand County Disappearing: Frac sand mining has exploded in Wisconsin over the past two years, raising concerns about air and groundwater pollution in the western part of the state. Of even greater concern is where the sand goes: it's fueling a boom in hydraulic fracturing or fracking, a natural gas extraction technique that has contaminated drinking water supplies with methane and a soup of cancer-causing chemicals. (view small)

Mining In Northern Wisconsin: In 2002, another UW Geography grad student, Zoltán Grossman, created a map showing all of the active prospects for mines in the northern part of the state. Mining is once again a hot-button political issue, so I decided that an updated version of Zoltán's map would be a useful information resource for the concerned public. We worked together to update and distribute the map, keeping the original black-and-white design for simplicity and reproduceability.

Water On the Line: I believe in using maps to advocate for communities and the environment. My map of the proposed Penokee Mine site in northern Wisconsin was reprinted hundreds of times and used by legislators, local residents, and environmental activists around the state.

Other Penokee Maps: Between 2012 and 2014 I made a number of maps of the Penokee Hills and Bad River Watershed, both for public use and for activists seeking a better understanding of the scope of the proposed mine. Although less widely distributed than Water on the Line, many of these maps were nonetheless used by many and had an impact on the struggle. The Penokee Mountains Heritage Park map in particular was an imaginative collaboration with the Lac Courte Orielles Tribe's Harvest and Education Learning Project to envision what kind of cultural, economic, and recreational resource the Penokee Hills could be if preserved for future generations.

Madison Light Rail: What if Madison, Wisconsin had a light rail transit network? What would such a network look like if developed cost-effectively, using mostly existing rail corridors? What benefits could it bring to workers, commuters, and the local economy? I became curious about these questions and decided to pursue them through an independent mapping, spatial analysis, and info graphic project over the summer of 2014.

Passenger Rail in the United States: The U.S. once had the most advanced, widespread passenger rail network in the world. Our system today is a shambles, while other nations continue to make advances that put rail as the cleanest, safest, most comfortable, and in many cases fastest way to travel. High-speed rail advocates in this country have put forward proposals for decades, but keep running into a brick wall of powerful car makers and oil companies that keeps the federal subsidies to new road construction flowing. The recent $8 billion infusion of cash is a start, but miniscule compared to what the feds pump into car travel every year and what is needed to get us back on track. This graphic poster makes the case for a real rebuilding effort that could put a nation to work and slash our use of fossil fuels. Find a high-resolution version here.

Child Suicide: Choropleth maps are dramatic representations of data that activate visual thinking, allowing the map user to make meaning from information that would be otherwise tough to parse. Difficult problems and overlooked topics can be brought into the light of public scrutiny, creating a force for change.

Major Coal Mines: Much scrutiny has been given to the destructive practice of mountaintop removal coal mining in Appalachia, but as I was surprised to discover while making a Wikipedia-style proportional symbol map of this dataset, the vast majority of domestically-produced coal now comes from mines in Western states. In fact, only two of the 60 most-producing coal mines are West Virginia MTR mines.

Ashland County Themes: These maps required a combination of spatial analysis operations along three different themes. I went beyond ArcGIS and added a little extra flair to them in Illustrator.

Duluth Trails: An as-yet-unfinished project predating my move to grad school, I intended to create a trail guide to Duluth, Minnesota and vicinity. This urban metropolitan area contains thousands of acres of public land ranging from developed parks to near-wilderness, and over 100 miles of nonmotorized recreation trails. I wrote descriptions and created aesthetically-pleasing maps of most of the trail systems in and around the city.

Interactive web maps:

MapStudy: This is a web framework I designed to allow researchers to easily create map-based survey applications for hypothesis testing. It currently uses Leaflet on the client side, but is intended to eventually support the creation of maps using D3, MapboxGL, REST services, static images, and embedded frames. It is configurable with a wide range of interactions and design choices and collects both form input data and user interactions, storing them in a database and/or e-mailing them to the researcher directly. I constructed it with a modular MV* architecture using Backbone.js. MapStudy is an open-source project hosted on GitHub and very much a work in progress.

Senegal Transhumance: This map was designed to display data collected on livestock resting points and watering points along herding corridors in western Senegal, and to allow additional data to be uploaded by trusted local parties. The goal of the project is to provide Senegalese policymakers with an idea of where herding routes—and thus herders' livelihoods—are threatened by agricultural expansion. The project is directed by UW Geography Professor Matt Turner; the data was collected by Senegalese research assistants and processed by other UW-Madison graduate students. The map will officially launch in the spring of 2016.

Global Madison: This is an online, responsive situated learning application designed for the Introduction to Global Studies course at UW-Madison. Designed for mobile, it provides a browser-based guided tour of five key sites in Madison's East Isthmus for investigating changes in different aspects of the global economy from Fordist to Post-Fordist production regimes. The application was designed by a graduate seminar class in which I took part, and I completed the necessary code during the summer of 2014. The app was assigned to students in the Global Studeis course in the fall semesters of 2014 and 2015.

Interactive Sankey Diagrams: I created these visualizations using D3.js to explore the interactions of users with my Master's Thesis wikimap (see below). One Sankey diagram shows the frequency of all pairs of interactions performed in sequence, while the other two visualize interaction paths taken by different users through the application. These visualizations illuminated the interaction strategies of different map users.

Bad River Watershed Wikimap: For my Master's Thesis project, I developed a crowdsourced web map, or 'wikimap,' of the Bad River Watershed in northern Wisconsin. The map displays features in the watershed added by users, along with user-added text, photos, audio, and video. The goal of the wikimap is to publicize the landscape values associated with places in the watershed that give those places special meaning. The map was built entirely with open-source technologies; the interface uses the Leaflet web mapping library, and the data is passed through PHP, stored in a PostGIS database, and served back to the map by Geoserver as an OGC Web Feature Service.

D3 Lab Prototype: I developed this coordinated visualization example using the D3 JavaScript library, and wrote an accompanying tutorial, as a contribution to updating the UW-Madison Cartography curriculum. My work was used for the third lab in the Interactive Cartography course, replacing a former lab that relied on Adobe Flash. A later version of the prototype and tutorial was published in the cartography journal *Cartographic Perspectives* and is available on GitHub.

Leaflet Lab Prototype: I developed this simple Leaflet web map example, and wrote an accompanying tutorial, as a contribution to updating the UW-Madison Cartography curriculum. My work was used for the first two labs in the Interactive Cartography course, replacing former labs that relied on Adobe Flash.

Queen City Icons: This modest project involved creating a library of icons representing 16 distinct feature types with local significance for Cincinnatians in three broad categories. I used the well-worn Google Maps API (v3) to generate and style the map. It was both an exposition of my skills as a low-pixel-count artist and an exploration of how I make meaning of the places I think of as important in my original hometown.

Renewables Around the World: Over the summer (2012), I participated in a comparitive study of four web mapping technologies run by Dr. Robert Roth through the UW-Madison Cartography Lab. We were asked to map data from the Organisation for Economic Cooperation and Development about energy use from renewable sources in forty countries between 1971 and 2010. I used were the Google Maps API to create my version.

Web Map Services Demonstration Page: Last summer (2012) I had the opportunity to teach myself JavaScript and delve into the exploding world of web mapping libraries, APIs, and services. I put together this page as a way to expose the guts WMS and other RESTful service requests for a tutorial presentation I gave to the student-run GIS Collective. Bonus photo: Me (right) with other members of the GISC during one of our summer collaboration sessions.

Wisconsin Sea Grant Story Map: One of the coolest things about building interactive web maps is the sharing of insights among the online community and the ability to build on the work of others. This was a JavaScript web mapping project that I did for an employer building on one of a series of templates built by programmers at Esri and made available to the public to tell the story of the work that Sea Grant as done around Wisconsin.

Flash maps:

Madison Gap Map: For this project I had the opportunity to work with two peers in the UW Cartography program and a team from the UW Madison Educational Policy Studies program. We created a geovisualization application to examine trends in Madison's student demographics and school achievement metrics, with the goal of addressing the achievement gap between students of different races.

World Mega Cities: This Flash-based interactive map provided my very first computer programming experience. Disclaimer: It was done for a class, not really for the BBC. And it's way cooler than any maps that are actually on the BBC's website. Please don't sue me, Englishpeople.

Lake Superior Watersheds: This was my second Flash map, delving into the world of geovisualization. What I wanted to accomplish required a novel geoprocessing method, for which I used ArcGIS to derive each individual watershed's percentage of each land cover type based on the National Land Cover Dataset (NLCD 2006).

PDF Resumé — last updated 03.22.2017

PDF Curriculum Vitae — last updated 03.22.2017

Northlandia—A Blog About Maps: My personal blog features posts about what I'm working on and learning and want to share with the world. Check it out!

Web Mapping Overview Series: I put together an eight-part blog series detailing what I learned during my summer studying web mapping technologies in 2012, so that others who are just starting out might be able to pick it up faster and not be intimidated. Out of this work, I produced a white paper for UW Sea Grant.

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Sack, C.M. and R.E. Roth. 2017. “Design and evaluation of an Open Web Platform cartography lab curriculum.” Journal of Geography in Higher Education 41(1): 1-23.

Abstract: Recent shifts in web map technology away from proprietary software and toward development on the Open Web Platform have increased the number and complexity of technical skills needed to do cartography on the Web. Web-based cartography curricula likewise must be adapted to prepare geography, cartography, and GIS students with the skills needed to make use of open source technology. This paper describes the design and evaluation of a novel curriculum for the laboratory component of a web mapping course offered by a university geography department. We drew from constructivist educational theory to create a scaffolded and spiralled lab curriculum that builds on prior understanding and progressively increases student independence and confidence. We evaluated the success of the new curriculum through an instructor log, student feedback on assignments, and an exit survey. The evaluation revealed significant growth in student abilities and confidence in the use of Open Web Platform-based mapping tools as a result of the curriculum scaffolding. This research provides a methodology for designing and evaluating curriculum around highly technical skills that are increasingly in demand in research, education, and industry careers.

Sack, C.M., R.G. Donohue, and R.E. Roth. 2014. “Interactive and Multivariate Choropleth Maps with D3.” Cartographic Perspectives 78: 57-76.

Tutorial for the On The Horizon section of the journal.

Roth, R.E., R.G. Donohue, and C.M. Sack. 2014. “A Process for Keeping Pace with Evolving Web Mapping Technologies.” Cartographic Perspectives 78: 25-52.

Abstract: The current pace of technological innovation in web mapping offers new opportunities and creates new challenges for web cartographers. The continual development of new technological solutions produces a fundamental tension: the more flexible and expansive web mapping options become, the more difficult it is to maintain fluency in the teaching and application of these technologies. We addressed this tension by completing a three-stage, empirical process for understanding how best to learn and implement contemporary web mapping technologies. To narrow our investigation, we focused upon education at the university level, rather than a professional production environment, and upon open-source client-side web mapping technologies, rather than complementary server-side or cloud-based technologies. The process comprised three studies: (1) a competitive analysis study of contemporary web mapping technologies, (2) a needs-assessment survey of web map designers/developers regarding past experiences with these technologies, and (3) a diary study charting the implementation of a subset of potentially viable technologies, as identified through the first two studies. The process successfully achieved the practical goal of identifying a candidate set of web mapping technologies for teaching web mapping, and also revealed broader insights into web map design and education generally as well as ways to cope with evolving web mapping technologies.

Donohue, R.G., C.M. Sack, and R.E. Roth. 2014. “Time Series Proportional Symbol Maps with Leaflet and jQuery.” Cartographic Perspectives 76: 43-66.

Tutorial for the On The Horizon section of the journal.

Sack C.M. 2013. “User-Centered Design for Coastal Web Atlas Maps and Tools: A Process Manual.” Wisconsin Coastal Atlas White Paper.

White Paper produced for the UW Sea Grant Institute.

Sack, C.M. 2013. “Tools and Best Practices for Coastal Web Maps.” In: CoastGIS Conference 2013: Monitoring and Adapting to Change on the Coast. Eds. Devillers, R., Lee, C., Canessa, R. and A. Sherin. pp. 160-164.

Abstract: The advent and speedy advancement of internet-based mapping technologies have made possible the collaborative creation, analysis, and sharing of geographic data on a breathtaking new scale. Emerging technologies can benefit coastal management agencies by providing tools for effective use of geographic data by managers and the public. However, their application also demands an ongoing investment of research, training, and work hours, warranting a comprehensive reference to the field of technologies and best practices for their use in the coastal setting. Essential elements for developing useful coastal web maps include compliance with technical standards set forward by the Open Geospatial Consortium (OGC), attention to cartographic conventions, and interactivity that fits the goals of coastal atlas developers. This paper is limited to a discussion of key examples of current web mapping technologies and how they might best be implemented as part of coastal web atlas development.

Sack, C.M. 2013. Mapmaking for Change: Online Participatory Mapping Tools for Revealing Landscape Values in the Bad River Watershed. Master's Thesis. Madison, WI: University of Wisconsin-Madison.

Abstract: The research reported here contributes to an emerging understanding of crowdsourced information and collaboration in the Geoweb. Its focus is Online Participatory Mapping (OPM), or the public, collaborative synthesis and presentation of Crowdsourced Geographic Information to support the goals of a community. This research draws from the fields of GIScience and participatory development practice to examine how new Geoweb technologies might empower communities to promote their own values and agendas when faced with contentious land use issues. It tests whether crowdsourced web maps can replace or complement specialist-generated geographic information with local knowledge and landscape values.

Sack, C.M. 2013. “Designing Map Democracy: The Creation of the Bad River Watershed Wikimap.” In: Proceedings of the Association of American Geographers.

Abstract: This paper describes the user-centered design and evaluation of an online participatory mapping application, or wikimap, for revealing narratives of place and landscape values in northern Wisconsin’s Bad River Watershed. The wikimap represents an emergent use of volunteered geographic information (VGI): collaborative mapping of local knowledge and values to support the goals of a community. Geoweb technologies are broadening Cartography, challenging specialist control over mapmaking by providing tools that allow the general public to participate to a greater degree. Participatory web maps that support VGI may help empower marginalized voices in land use decision-making if built with these users in mind. To explore what tools and interaction strategies should be supported in the wikimap to best fulfill this democratic promise, a user-centered design approach was applied during the development of the wikimap. The process began with a needs assessment consisting of eight interviews with stakeholders from natural resource agencies and nonprofit community groups active in the Bad River Watershed. Participants’ answers were analyzed to inform the conceptual design of the wikimap, including the user objectives, information types, and key interactions it should support, as well as ethical considerations and strategies for promoting participation of local residents. Multiple prototypes were developed, with feedback obtained from participants on each. A final stage of user testing currently is in progress. Insights from the development process will be synthesized into recommendations for designing similar applications to meet the needs of community stakeholders dealing with important land-use issues.

Sack, C.M. 2013. “Mapping Sense of Place: Online Participatory Mapping for Indicating Landscape Values.” In: Proceedings of the 26th International Cartographic Conference.

Abstract: The past decade has witnessed the immense growth of online geographic information technologies and crowdsourced geographic information. The increasing involvement of non-specialists in the Geoweb has been interpreted as dismantling elite Cartography and re-empowering every human’s innate mapping ability. But this assertion may belie the multitudinous and even conflicting goals of different uses of crowdsourced geographic information, which can be disempowering as well as empowering. This paper explores the potential of online participatory mapping as an empowering use of Geoweb technology. It describes a case study that employed user-centered design to create a crowdsourced web map for community-driven mapping of places and landscape values.

Roth R.E., R.G. Donohue, C.M. Sack, T.R. Wallace, and T.M.A. Buckingham. 2013. “A Process for Assessing Emergent Web Mapping Technologies.” In: Proceedings of the 26th International Cartographic Conference.

Abstract: The current pace of technological innovation in web mapping offers new opportunities and creates new challenges for web cartographers. The continual development of new mapping applications and solutions produces a fundamental tension: the more flexible web mapping options become, the more difficult it is to maintain fluency in using and teaching these technologies. We address this tension by describing a case study process completed to meet the needs of the University of Wisconsin‒Madison Cartography program. Specifically, we conducted a sequence of three studies: (1) a competitive analysis study of contemporary web mapping technologies, (2) a needs assessment survey of internal designers/developers regarding past experiences with these technologies, and (3) a diary study charting the implementation of a subset of potentially viable technologies for the program. The process successfully achieved the goal of identifying an appropriate suite of web mapping technologies for the UW program, but also revealed broader insights into web map design as well as ways to cope with evolving web mapping technologies.


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