Says @AndrewSkinner : "Sometimes it seems we are obsessed with using red and green in our maps. It’s an easy option! Red for bad, green for good … yes? But some users have difficulty differentiating between red and green. About 8% of the world’s population (overwhelmingly, but not exclusively, male), suffer from some form of color blindness, and over 99% of them have a red-green deficiency."
There's a lot you can do using Media Map, one of the configurable apps that supports swipe. Here's an example of how you can use swipe to visualize Living Atlas content, in this case using three layers from NOAA that helps us understand sea level rise and its impacts to coastal areas.
The Community Maps Program enables community contributions of authoritative data to help build the ArcGIS Living Atlas. You can provide feedback, create detailed features, and share data layers and services, contributing to Esri basemaps that anyone can use....
Recently, users have asked us about basemaps that are accessible and/or color-blind-safe. In particular they have asked for maps that comply withWCAG(Web Content Accessibility Guidelines) standards, and the US Federal ‘Section 508’ equivalent. This presents a few challenges. A map can be a complex structure that relies on a well-developed hierarchy, and a basemap is an extreme example of that. Imposing a new set of rules on top can be a daunting prospect!
What follows is an attempt to get to grips with the graphic aspects and to present you with some alternatives.
What are the standards?
This is a difficult question, at least in how these standards relate to maps. The graphic requirements tend to concentrate on legibility of text (WCAG-AA standards call for a contrast ratio of at least 4.5 between text and background). It suggests that for many of our maps we could meet this requirement simply by changing labels to black, placing a halo behind them to act as the ‘background’, and leaving the rest of the content alone. A map is much more than just its labels though, and we want to improve the accessibility of the map content as well.
What is different about a basemap?
John Nelsonhas talked about ‘BASE-maps’ versus ‘base-MAPS’. A BASE-map is a deliberately subdued background map used as an underpinning for your information (think ‘Light/Dark Gray’ or ‘Topographic’). This is challenging if it is an accessible map, where contrast between symbols is important. A ‘base-MAP’ is a stronger reference map (think ‘National Geographic Style’), where your information is added to the overall picture. That makes accessibility easier to build-in. Either way there needs to be some room in the map hierarchy for the user’s information.
How can we approach this?
We need to find a balance between accessibility and functionality.
So, we can use a color-blind-safe palette and increase contrast between map features, to make the map work for a broader audience. This means that the map will use at least some strong colors and tones. We can avoid ‘fussy’ fonts that might be difficult to pick out of the background. And we can increase the size of labels (but carefully – we don’t want to swamp the basemap with words!). Haloes help with the legibility of labels, but they can be destructive to the rest of the map information.
Ultimately, we may have to consider cutting some of the content of the map.
I have created a map design that tries to walk a line between accessibility, and functionality as a basemap. It is more of ‘base-MAP’, but I’ve tried not to go overboard with it.
I have chosen Ubuntu as the font to use throughout the map. It has some character to it, but it is clear and legible.
All labels are in black or white.
Smaller labels are increased in size, but not to the point at which they take over the map. I use capitalization for some features (such as road/street names) to create a contrast with other labels.
All labels have haloes, but in most cases, I’ve tried to soften the impact of them by blurring the edges and adding a touch of transparency.
Using the basemaps
These basemap layers will be available for you to use at the URLs linked above for the foreseeable future. The map content is updated with our regular basemap data updates. I may make periodic changes to these map styles as needed based on your feedback and our experience using the maps.
If they prove popular, we’ll consider incorporating them into the core basemap set. We’ll try to give you plenty of warning if we decide to shut these URLs down and replace them.
I would appreciate any feedback you care to provide, either via the comments section below, or directly email@example.com.
Thanks! Andy Skinner
Color-blindness suitability was assessed using ‘Color Oracle‘. Color contrast was assessed usingcontrast-ratio.com.Thanks to Mark Harrower and Emily Meriam for their input.
The newest feature available inEsri Vector Basemapsis a tile set of contour lines. We’re including contours in a newmultisource tile layer,as part of a web map namedTopographic (with Contours). This detailed content covering the globe is available as a beta release for viewing through the new ArcGIS OnlineMap Viewer Beta, ArcGIS Pro 2.5 and newer, and Runtime apps built on 100.5 and newer. Users on older versions of the clients will only see the topographic map layers, not the additional contour layers.
Esri Vector Basemapsprovide users with a rich collection of map styles to choose from. The vector tile format allows for a nearly unlimited amount ofcustomizationof styles. Although available in ArcGIS Online for the past few years, we continue to roll out new features to enhance the experience.
These vectorized contours are published as their own hosted tile layer (World_Contours_v2). You can add them to any map, including your own custom style by using theWorld Contourstile layer.
In our newTopographic (with Contours)web map, the contours are not just draped on top of the map. In fact, the contours are not even added to this web map as a separate layer. The contours are included within a singletopographic vector tile layer, integrated with the rest of the basemap features. The contours start displaying at LOD 11/1:~144K scale.
The newWorld Topographic Map (with Contours)vector tile layer has a root.json file that includes two vector tile sources. This tile layer with multiple sources is an example of amultisource tile layer. Displaying two or more vector tile sources in a single tile layer, i.e. as a multisource tile layer, is possible when using the new Map Viewer Beta.
The JSON code in a multisource tile layer includes paths to two or more vector tile services. In ourWorld Topographic Map (with Contours)layer style, the two sources are namedesriandcontours. Theesrisource includes all the features drawing the topographic map. This includes land color, water fill, park polygons, roads, and map labels. Thecontourssource includes features that draw the contour lines and contour labels.
The benefit of a multisource tile layer is that the features in the map are drawn from both sources and displayed in the proper display order. This is achieved by including the JSON layers from both set’s vector tiles. Layers to draw contour lines are ordered in their proper position of the code, above the land tints and below the water lines. Layers for the contour labels are ordered with other map labels near the end of the root.json code.
Single source root.json style file (basemap source = esri)
Topographic web map without contours (top) | Topographic (with Contours) (bottom)
We encourage users to migrate and use theEsri vector basemaps. The addition of contours brings parity between the vector topographic map and raster topo version in terms of map content.Review our plan for moving many Esri raster basemap services into mature support in the next year.
How else can users take advantage of multisource tile layers?
Users can create a VTPK in Pro from their own data and publish it as a hosted tile layer. It can be combined with any of the Esri Vector Basemap styles, much like our contours. By editing the style JSON and adding the additional source and feature layer code, user-generated tiles can be integrated in the map display at any level of the map stack. For example, users could position the code for their content below other map labels without having to use separate base and reference layers. Using a multisource tile layer, there is only one map layer rendering all the content.
Users can create their own tiles in Pro and combine any multiple number of layers in the same coordinate system and tiling scheme.
In addition to the new Map Viewer Beta in ArcGIS Online and Enterprise 10.8.1, multisource tile layers can be viewed in ArcGIS Pro version 2.5 or newer, apps using Runtime version 100.5 or newer, & StoryMaps. Users on older versions of the Esri clients will only see the topographic map layers, not the addition of the contour layer.
What’s next for the Esri Vector Basemaps?
A vectorized hillshade layer to replace the current raster service that’s included in vector maps such as Topographic or Street Map (with Relief). The multisource Topographic (with Contours) tile layer will include three vector sources: esri, contours, and hillshade, providing a full vector map solution.
Multisource tile layers are a new addition to the display and use of vector basemaps in ArcGIS Online. The ability to combine these multiple layers into one single vector tile layer allows a better representation of basemaps, especially in the case of our Topographic map with Contours, with the addition of our vectorized contour layer.
Bookmark thisEsri blog linkto keep current on vector basemap releases.
NAIP imagery has long been available inArcGIS Living Atlasas a dynamic image service, enabling image analysis on the 4-band source imagery dating back to 2010. However, for those who wish to leverage the imagery for visualization, the latest NAIP imagery has been optimized for display quality and performance in the form of a new tile layer.
On top of that, the NAIP imagery has been enhanced to provide the best results. See the before and after below:
In addition, the metadata display has been improved, meaning you have instant access to the source, acquisition date, accuracy, resolution and more. All available with a single click.
ArcGIS Living Atlas of the World provides foundation elevation layers and tools to support analysis and visualization across the ArcGIS platform. These layers get updated quarterly with high resolution elevation data from open sources and community maps program. In a recent release, world elevation layers are updated with bathymetry and a few high-resolution elevation datasets.
The Esri vector basemaps were updated this week with new content from our commercial data provider and community contributions. The content below details how you can influence map content and styling. Additionally, we’re sharing details on new and expanded map features. Check in on theVector Basemaps blogsfor related information.
Data Contributions and Community Map Editor
TheCommunity Maps Program for Basemapsuses the best available data sources to produce a wide variety of multi-scale, online basemaps. These maps serve as a foundation for almost any GIS task. Provide your organization’s authoritative data to enhance the map. If you don’t have a collection of data layers to provide, but still want to contribute, consider adding content through theCommunity Maps Editor app. Edit parts of the Esri Community Maps basemap to add detailed features for universities, schools, parks, landmarks, and other special areas of interest.
A key benefit using Esri Vector Basemaps is custom cartographic styling. Through the Vector Tile Style Editor, put a unique touch on your map’s look. The Quick Editor feature single click color changes across the map. Don’t like the results? Click again. Fine tune the map style through layer control changes. Turn features off. Change colors. Replace typefaces. Adjust line widths. These are the tip of what can be done to make your mark on your design. Theeditor is accessible through this appor from the “change style” icon in the map viewer. Seesupporting documentation.
Esri Vector Basemaps are now available in 24 localized languages. Another expansion in the Localization efforts is the map styles available. Our creative vector styles (Charted Territory, Modern Antique, Nova, etc.) are now included in the language/regional basemap galleries. Refer to thisFAQ answerfor the list of available languages of the Esri vector basemaps.
Asreported earlier this year, our collection of Beta layers include extended points of interest. We initially included millions of places in the United States usingSafeGraph Placesas the data source. In this week’s release, we expanded our global reach outside the U.S. Millions more restaurants, stores, businesses, and other POIs are in the map from HERE Places Extract data.We’ll continue to improve the Beta items before a production release.
Esri User Conference
This year’sEsri User Conferenceis a virtual event on July 13 – 16, 2020. Many sessions related to theArcGIS Living Atlasare available this year. Basemaps, the Style Editor, and Community Maps are a few of the topics covered. The U.C. event also provides an opportunity to connect with Esri cartographers and other staff. Navigate to the Basemap & Community Maps page. We’re part of the Living Atlas and Location & Data Services area.Register todayand check us out.
Need to make a correction to one of our maps? OurFeedback Servicesare built for this purpose. Mark up the map and enter the details. We’ll review and publish the edit to the basemaps.