Kenneth Field
Recent Posts
Red, Blue and Purple: mapping the 2012 US Presidential Election
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very time an election occurs, maps become a key component in telling the story, but what type of map best tells the story of the winners and losers? Red/blue choropleths? Areas shaded in an array of purples? Value by alpha maps? Dot density by County? Ultimately, the areas used (e.g. Counties) are arbitrary, exhaust space and dictate the visual pattern we see. We can warp them into cartograms but these sometimes distort geography too much for them to make much sense. The patterns we see are as much a product of the boundaries as the voting patterns of real people in real places. This blog entry explores different ways to map election results and describes a different type of map we made to show the 2012 Presidential election results…it’s a multiscale dasymetric dot density web map (viewable on ArcGIS Online).
Using Stamen and MapBox tilesets as basemaps in ArcGIS.com
In his recent blog entry Adding tile layers to your web map, Chris Whitmore explained how the March 2013 enhancement to ArcGIS Online supported the addition of a range of new file types to web maps. Chris described the approach of adding tile layers to web maps which allows you to use web-accessible map tiles from a server directly using a URL request from the browser. In this blog entry I show you how this approach can be used to integrate Stamen and MapBox tilesets in your ArcGIS Online web maps.
Over the edge 3D: designing the deaths in Grand Canyon map
This blog entry explores a little of the design, authoring and publishing approaches we took when creating a map of all known deaths in Grand Canyon. Actually it’s two maps…a print map and a web map and we’ll think about the different design and technical constraints we dealt with and opportunities we were able to leverage with the different mediums to make each version work effectively as an information product. We also share the style files and other components so you can try out some of the 3D cartographic effects yourself. Continue reading
Telling thematic stories in ArcGIS Online
By Kenneth Field (Research Cartographer), Damien Demaj (ArcGIS Online Cartography) and Linda Beale (Geoprocessing)
At the 2012 Esri Education GIS Conference and the 2012 Esri International User Conference, we demonstrated how you can build informative thematic maps using the ArcGIS System. The purpose of the sessions was to take relatively simple datasets and create a range of alternative thematic map types that told a story in different ways. This demonstrated the techniques for creating the maps using ArcGIS for Desktop as our authoring environment and ArcGIS Online as our publishing mechanism. As the XXX Olympiad is currently taking place in London, UK we illustrated how alternative maps can be made to tell different stories of the relative success of nations over the period since the first Olympic games in 1896. Continue reading
Using a binning technique for point-based multiscale web maps
By Kenneth Field, Esri Research Cartographer
Presenting point-based data on a web map is challenging because of the problem of overlapping symbology, particularly as you zoom out of the map to view data at smaller scales. So-called push-pin web maps are very easy to make with ArcGIS Online but making the map make visual sense at the smaller scales requires a little more work. In this blog entry we illustrate how data binning can be used to aggregate large point-based datasets into hexagonal polygons to overcome the problem and improve the web map across all scales.
Using alternative thematic basemaps with ArcGIS.com map viewer
By Kenneth Field, Esri Research Cartographer
The default projection for all basemaps in ArcGIS Online is Web Mercator. In a previous blog entry, Bern Szukalski explained using custom basemaps as an alternative to Web Mercator and the ArcGIS Resource Center provides information on how to build online basemaps. Mercator projections are very useful for certain mapping tasks but not so good for others because they dramatically exaggerate northern and southern latitudes. This exaggeration deforms the shape and size of areas. Whilst Web Mercator has become a widely adopted web mapping standard (because of the tiling system being well suited to this spatial reference), there are situations where you may want a different map projection. In thematic mapping, for instance, you might want to preserve areas or shapes or even use a more pleasing view of the world than Web Mercator provides at small scales. This blog entry describes how you can switch out the default basemap for your own, simplified thematic basemap.
Creating a time aware web map for the torch relay event
By Kenneth Field, Esri Research Cartographer
In the lead up to London’s big sporting event in July 2012, the symbolic torch will travel the length and breadth of the United Kingdom. The route has been designed to maximize the opportunity for the UK population to view the torch as it makes its way, across 70 days, stopping at over 1000 locations where bearers will parade the torch locally. The torch relay event web map provides a time aware window on the event for locals to follow and for more distant observers to explore.
Creating a multimedia trail web map
By Kenneth Field, Esri Research Cartographer
Tourist trail maps engage people new to an area and guide them to sights of importance or interest, often using a particular theme. The Esri story maps team recently published a trail map of New York City’s High Line and also a short walking tour around Esri’s Redlands campus. Both examples illustrate the way in which web maps allow you to combine basemaps, route information, point of interest markers and multimedia (e.g. photographs) to tell a rich visual story. Web maps like these can be used either as a virtual tour to give a narrative without actually visiting the area, or as a navigation aid as users follow the trail in reality using a hand-held device. In this blog entry, we’ll look at how you can make a walking trail web map. Continue reading
Using a mapmaking checklist for map design
By Kenneth Field, Research Cartographer, and Damien Demaj, Online Cartographic Product Engineer
We all have favorite maps that we think are great, but rather than just saying a map looks great, how many of us are able to take a critical look at it, evaluate it, and explain why it looks great? Having the ability to reflect on and evaluate maps as information products is important to understanding effective cartographic design so you can optimize communication of the intended message in your own maps as well as be able to understand why other maps work. In this blog entry, we’ll briefly look at some static maps and a web map to see what we think makes them great and then show you how using a checklist gives you the tools to reflect on maps in the same way. Continue reading
Pie sector features communicate multivariate data
By Kenneth Field, Esri Research Cartographer
In many industries, simple geometric shapes such as squares and circles do not adequately represent objects. Some phenomena are just more complicated and require alternative approaches to represent them meaningfully. We had a question on Ask a Cartographer recently about creating pie segment shapes as features to support a requirement in the telecommunications industry. The geometry of the feature needed to represent the signal emitted from a cellphone mast. This sort of geometry cannot be built out of the box but by using Python we were able to build a custom Geoprocessing tool that could automate the process and build the features required. In this blog entry we explain why a pie segment better represents a cellphone signal, how they were constructed and what data are needed to run the tool. We also share the Geoprocessing tool so that others with this requirement can make similar maps. Continue reading
