Monthly Archives: October 2009
To get in the Halloween spirit, I created a layer package of data from the 2007 US Census of Agriculture about pumpkins, and shared it on ArcGIS Online [view layer package here (181 KB)]. You can explore where pumpkins are grown using this data and ArcGIS Desktop or ArcGIS Explorer.
I was inspired by Chris Kollen, a librarian at the University of Arizona, who created maps of potential Trick-or-Treaters (based on the population of 5-13 year olds) and the distribution of bats in Arizona.
What other Halloween topics could be mapped? The US Census Bureau issued a press release of Halloween facts and figures (which they do for several holidays each year); perhaps you’ll find inspiration there. Personally, I’d like to research the production of chocolate next…
In a recent ESRI EdCommunity blog, I described how to download and use a script to create cartograms in ArcMap. While I examined total CO2 emissions by country, the same tool can be applied to any data at any scale. Because I consider cartograms to be an excellent research and teaching device, I then examined a historical county data set from 1900 to 2000. I was interested to see what cartograms would reveal about historical population trends for specific areas and discovered that they serve as a springboard for discussion about the forces responsible for such changes.
I created a cartogram for the past 100 years for Colorado. I joined the resulting cartogram feature class with the original data on the field “ObjectID” so that I could examine the population attributes. The maps comparing 1920 with 2000, below, show differences and similarities.
As expected, Denver County dominates in population each year. Was it natural to locate the state capital there, or did its capital status encourage subsequent population growth? Denver’s population, at 256,000 in 1920, doubled to 527,000 by 2000, but the state population more than quadrupled, from 939,000 to 4.3 million. Consequently, the cartogram’s “area” represented by Denver’s population decreased from 47,000 to 32,000 square kilometers as Denver’s share of the state total dwindled from 27% to 12%. Pueblo and Weld also decreased in relative size between 1920 and 2000, but for different reasons. Pueblo County’s share decreased with the decline of its iron and steel industry. Weld County’s share decreased due to the rise of agribusiness until 1980, but then experienced rapid suburbanization along with much of the High Plains. Agricultural counties outside of this zone decreased in size on the cartogram and in absolute population, evidenced in the shrinking of counties like Cheyenne and Prowers along Colorado’s eastern border. Also noticeable is the rise of suburban counties such as Douglas, Jefferson, and Arapahoe.
What do you think your state will look like over the past 100 years? Use the cartogram tool to find out!
Recently PBS aired The National Parks: America’s Best Idea. The series has inspired this sequence of blog postings about aspects of my personal park explorations over the years. I’m using ArcGIS Explorer (AGX) in the investigation. See other national park blog posts for more (including details on performing some functions listed below).
We’re moving through my Fav 7. Today, Redwood…the last stop. In exploring my other top parks, a theme rings out—geology and related threads. In a trip to this park, the geologic setting is very much evident but in my view, it’s impossible to not be humbled to silence and awe not by the landscape, but what’s on it—living things, the Redwoods. These trees, Sequoia sempervirens, represent the tallest and are among the longest and oldest living entities on planet Earth…and they only live in one place—along the US Pacific Coast from southern Oregon to Big Sur, California. In preparing for this entry, I did a bit of Web research on the trees, the park(s), and aspects such as the importance of fog as a key part of the overall water supply for the trees. Also, I was excited to see that the redwoods (range, threats, sustainability, history) were the October 2009 cover story of National Geographic magazine.
Using AGX, I do several things I’ve not covered in this series so far: Download and add a park boundary shape file from the National Park Service Data Clearinghouse (NOTE: Not all NPS data are ready for immediate direct use by AGX), plan a trip to a few key park sites, and check the weather for our trip.
To start, I create a Redwood folder for content (layers, Web research, views). Next, I add the NPS Klamath area parks boundary file and zoom to the Redwood NP extent. Where to go next?
A great place to stay in Crescent City, CA is the Hampton Inn. Using its address and ZIP (100 A St, 95531), I locate and add it to my map. The places I want to visit include the Hiouchi Information Center, the Stout Grove (by way of the Howland Hill Scenic Road), and the Klamath River Overlook. I use the Notes feature to pinpoint the places I want to explore.
Using the AGX Route function, I add the route sequence and execute the multistop route and derive a useable map for my day’s travels.
What’s the day’s weather like for the Redwoods? Check out the AGX Weather Forecast Add-in.
Stay tuned for the final installment in this series.
We tend to focus on the analytical capabilities of GIS, and rightly so, as that is its major strength. However, GIS can also be used to quickly create customized maps. These maps can be used by the instructor to support a lesson, or by the student to support an oral or written report. Frequent requests such as, “Does a map exist that just shows rivers and countries of Africa but without the country names?” have frequently appeared on listservs and blogs over the past 15 years. Such a map may not exist online or in a textbook, but can easily be generated with GIS.
Consider the map I recently created below showing some major Amish communities in the northeastern part of the country.
While this map supported an article authored by a colleague for the Journal of Geography, it could just as easily be used to support a classroom discussion on the Amish in the USA. I started with the data packaged in the population change lesson on ArcLessons:
http://edcommunity.esri.com/arclessons/lesson.cfm?id=457. I unzipped the data, started ArcMap, and added the data layers. I zoomed to the study area, labeled three states, exported my counties of interest to a separate data layer, symbolized them as black, and added numbers and leader lines. For the inset map, I created a new data frame, copied the state lines into it, and drew a study area box. I created a layout, inserting the northeastern USA and 48 states data frames. I exported the map as a grayscale image. In a short amount of time, I had created a customized map.
What sort of map do you or your students need? Central Asia ecoregions? Michigan lakes and rivers? Phoenix median age by neighborhood? Using data sets from ArcLessons, data portals, or from the ESRI Data and Maps DVDs, allows for you and your students to create exactly the maps you need in ArcMap.
Upon further reflection, even these customized maps in turn support critical thinking, so we are right back to analysis!
The Geospatial Semester is a unique project where high school seniors in Virginia study geospatial technologies and do locally-based projects as they earn college credit from James Madison University. They learn cutting edge 21st Century Skills as they begin the transition from high school to higher education or the world of work.
The project’s brand new website is available at http://www.isat.jmu.edu/geospatialsemester/
It features student projects, a map of participating schools, prize-winning maps and more. For more information, contact Dr. Bob Kolvoord (email@example.com).
The Scholars’ Lab at the University of Virginia Library will host two rounds of an NEH-funded Institute for Advanced Topics in the Digital Humanities, on the theme of Enabling Geospatial Scholarship. A first four-day event (November 2009) is geared toward 20 library, museum, and digital humanities center professionals, and aims to shape policy and build the technical capacity of the institutions they represent to support boundary-pushing geospatial scholarship.
A second round of the Institute (May 2010) is geared toward humanities faculty members, graduate students, and other scholars. An opening discussion will identify central questions facing the studies of space and place in the digital humanities. Martyn Jessop’s 2008 article on inhibiting factors in humanities GIS will serve as a guide, and Jessop will present his work. Participants will explore a variety of tools and core GIS concepts through hands-on activities, and discuss the challenges of applying science-based GIS tools to research in the humanities.
See the Institute’s home page for more information. Participants will be selected through a competitive application process.
-Angela Lee, ESRI Education Programs Manager
Recently PBS aired The National Parks: America’s Best Idea. The series has inspired this sequence of blog postings about aspects of my personal park explorations over the years via ArcGIS Explorer (AGX). See other national park blog posts for more.
We’re moving through my Fav 7. Today, Acadia—the first national park east of the Mississippi River (1916). I have only been to Acadia once and then not for long enough. Regardless, it quickly got added to my list of favorites—rugged terrain, ocean, great vistas, rich woodland vegetation, and of course, geology. Touring the park you’re quick to recognize some interesting features and many of them expose a glacial past—U-shaped valleys, a North American fjord, erratics, and glacial polish and striations abound. Also, as the Pleistocene ice met the surface features, they encountered resistance—igneous, granitic objects like Mt Cadillac, the remains of an ancient caldera.
Using AGX, I tackle several things: Simply explore the park from a vantage not possible by ground observation to note some of its characteristics (including glacial features), use Web research to learn more about the park and its primary component—Mt Desert Island—and build a Background folder of Web content, identify an aspect of glacial extent in the region, and add some key Notes. (NOTE: I wanted to add an outside GIS layer or two on geology and glaciation but was unsuccessful in my initial searches. However, as I sent in this post, I remembered that the National Atlas has data on glacial limits. I will include the layer in a future expansion of this project.)
As with other parks, I begin by creating an Acadia folder for content. Next, I create contextual Views allowing roaming and easy return. My Web research nets a number of key references on the area’s glacial and bedrock geology. I add them as Links to a new Background folder. In the process, I discover that the 1 km thick ice sheet that covered the park extended, at maximum, some 370 miles into the Gulf of Maine and I want to highlight that using the Measure function to add a line of that distance to my map. I also add information in its associated Pop-up, again using lessons learned at the AGX Resource Center blog > text…HTML.
For the remainder of this first Acadian pass, I add a few photographic notes—one of mine as local content on the granitic shoreline and others focusing on glacially-influenced features using Web links.
Stay tuned for the next installment.
- George Dailey, ESRI Education Program Manager
At my first ever geography teacher institute, at Macalester College in 1986, one of the leaders held up a data table and said “Look at this table! Just look at it! You can just … just … put your ear up close, like this, y’see … and hear it crying out … ‘I wanna be a map!’” Ever since the dawn of ArcView2 — long before “mashups” became popular — I’ve been happily joining external data tables to shapefiles in order to make dozens of new maps.
I never tire of it. To this day, joining tables to existing features remains, in my mind, one of the most powerful capacities of GIS. It opens up vast galaxies of exploration! And talk about math! Going through banks of numbers and looking at ways to classify them, query them, normalize one by another, sort and sum and statisticalize them (huh?), is a powerful way to build understanding of a given data set, and how one item relates to another.
The other day, I saw an email from the National Center from Education Statistics, describing new data about public schools from the 2007-08 school year. The PDF document had a set of six tables about the 50 states. I downloaded it and took about 20 minutes to convert them into one long spreadsheet (Excel file). Then it was time to play with the data.
Above you can see one look at the student/teacher ratio. Below, you can see one look at the ratio of students eligible for free or reduced lunch. (It also helps to look at the original PDF document.)
There’s never an end of data to explore. Joining data tables to existing features is a piece of cake in ArcView. Try it, and maybe you too will be able to look at the table and hear it crying out … just listen … it wants to be a map!
- Charlie Fitzpatrick, Co-Manager, ESRI Schools Program
Cartograms, because they distort our normal view of things, are wonderfully rich research and teaching tools. A distance cartogram shows relative travel times and directions within a network. An area cartogram is a map in which some variable is used instead of the land area in each polygon to compute the size of that polygon. Many of us remember using graph paper to make rectangular area cartograms as undergraduates (but perhaps I am dating myself). Today, one can use Web GIS and desktop GIS to create cartograms. For example, nearly 700 variables can be mapped on www.worldmapper.org, and the data can be downloaded as Excel spreadsheets and analyzed within ArcGIS.
To dig deeper and make your own cartograms, with the ability to do bivariate analysis within a GIS environment, use the ArcScript cartogram tool that Tom Gross in the ESRI Applications Prototype Lab created, on: http://arcscripts.esri.com/details.asp?dbid=15638. How can a GIS, which focuses on the accurate spatial representations of features, be used to create cartograms? Try this script and find out!
Once you install the cartogram tool, inside ArcMap, access ArcToolbox. Create a toolset, add the cartogram tool, and run it. The intuitive interface allows specifying input and output, and even comes with a nice assortment of international population and other variables to practice on. You can distort the base layers so that your cartogram can include the distorted layers for reference. I did this for cities, a 30-degree world grid, and a satellite image of the Earth to see these reference layers overlaid on my cartogram.
In this example, I chose to map the total CO2 emissions by country in 2004, in millions of metric tons, from the US Energy Information Agency. What patterns do you notice?
The cartogram map layer has to be written into a geodatabase, but otherwise, the tool has few restrictions. I am very pleased cartographically with the results, and the methodology of how the cartograms are generated is well documented.
What other variables and scales could you map and analyze as cartograms?
The ESRI Education User Conference (EdUC) proposal deadline has been extended to November 13, 2009. Peer-to-peer presentations about GIS in education are at the heart of the EdUC – share your experience and wisdom with your colleagues by presenting a paper or poster. See the EdUC Call for Presentations for details.
For the 2010 EdUC, we are especially encouraging presentations on GIS in science, technology, engineering and math (STEM) education, multi-disciplinary projects, workforce training, GIS in school/campus administration, and ArcGIS Server-based teaching and projects.
The 2010 EdUC will be held July 10-13, 2010 in San Diego, CA.