GIS has radically changed how people create and engage with geographic information. Online maps shape the primary user experience, serving as both the means of creation and the mechanism for sharing and delivery. Interactive GIS maps are now used widely—traveling with us wherever we go. People have come to appreciate the power of combining layers of all kinds in their maps for a richer, more significant perspective about their world. With Web GIS, your maps can be accessed and put to work by virtually everyone, everywhere.
Maps are important. Everyone understands and appreciates good maps. GIS users create and work with maps every day—they provide the basic experience and a practical interface for the application of GIS. Maps are also the primary way that GIS users share their work with others in their organizations and beyond. Maps provide a critical context because they are both analytical and artistic. They carry a universal appeal and offer a clarity and shape to the world. Maps enable you to explore your data and to discover and interpret patterns.
Online GIS maps can be created by anyone using Web GIS—and can be shared with virtually everyone. These maps bring GIS to life and can travel with us on our smartphones and tablets. Online maps have forever transformed computing and the web.
Make no mistake, traditional printed maps are not going away. They continue to be important because they help you quickly grasp the broader context of a problem or situation. The best printed maps are true works of art that can stir your emotions and imagination. There’s no comparable large-format document that communicates and organizes such large amounts of information so effectively and so beautifully. Cartographers using GIS will continue their craft of making astounding printed maps that teach and amaze.
And this will always be the case. Large-format printed maps and their digital cousins (such as PDFs) will continue to significantly occupy the good work of many mapping professionals. The difference now is that GIS tools have come of age for spectacularly high levels of professional cartography
Meanwhile, a major online mapping revolution is under way, and the implications of this are far-reaching. We all know that consumer maps are ubiquitous on smartphones and the web. Map-based applications regularly rank among the most used programs on smartphones and mobile devices. Online maps have familiarized millions of people with how to work with maps, and this massive worldwide audience is ready to apply maps to their work in ever more imaginative ways using Web GIS.
Any map that you make can be saved and shared online—intended for a specific audience and expected uses. Online maps have an interface, a user experience (UX) that comes with each map, called an app. With the ArcGIS platform, a user (which you are by reading this book and becoming a member of the Learn ArcGIS organization) now has a wide range of options for designing and implementing purposeful maps and apps. The possibilities for engaging the audience that matters to you are endless.
Since the earliest recorded human history, maps have served to preserve and transmit geographic data by means of a visual representation. As such, they appeal to both the creative and logical aspects of our thinking; they’re artistic but also logically organized around location.
The best maps unlock the full potential of the underlying data. Although the makers of the examples on this page weren’t likely thinking about their knowledge of landownership or safe harbors as data, this information was valuable enough to commit to capturing in their respective maps. Although this book is primarily about modern digital interactive maps, it’s practical and inspiring to recognize that good maps utilize information design principles that have been evolving for centuries.
Online maps can also provide the same powerful emotional and visual appeal of the great, printed maps. The age-old idea of information arranged spatially and thoughtfully presented for an intended audience will always be the guiding philosophy behind the work of geographic storytellers.
Successful maps work because they present some piece of geographic information in ways that illuminate, elevate, distinguish, intrigue, inspire, and promote fresh perspectives or points of view.
People are visual learners and seem to be instinctively attracted to maps. Maps help us instantly perceive patterns, relationships, and situations. They not only organize and present the rich content of our world, they offer a unique contextual framework for understanding, predicting, and designing the future.
GIS has a unique capability to integrate many kinds of data. It uses spatial location and digital map overlays to integrate and analyze the content of our world, uncovering relationships among all types of data. Maps and data form the underpinnings of GIS, which then organizes information into separate layers that can be visualized, analyzed, and combined to uncover meaning in data. This combination has resulted in a powerful analytic technology that is science-based, trusted, and easily communicated using maps and other forms of geographic visualization.
Online maps provide the user experience of working with and deriving answers from GIS. Maps provide windows into rich information—you can reach into a map to extract all kinds of related information. Maps also provide analytic functions that derive new information layers that enable us to answer whole new kinds of questions.
As you read this book, you’ll understand that maps can be 2D and 3D, and they can animate information through time. Because you can add new layers from many sources, you can gain a new perspective and a deeper understanding about the problems and issues that you are trying to address.
Perhaps the most profound role that maps play is that they provide a platform for engagement and conversations, for representing many points of view, for understanding the perspectives of others, and for helping humanity find answers to the many problems we face, things we care about—worthy goals that we can come together on.
Web maps are online maps created with ArcGIS that provide a way to work and interact with geographic content organized as layers. They are shared across your organization and beyond on the web and across smartphones and tablets. Each map contains a reference basemap along with a set of additional data layers, plus tools that work on these layers. The tools can do simple things, such as open a pop-up window when you click on the map, or more complex things, such as performing spatial analysis and telling you the agricultural crop production in every county across the United States.
At their heart, GIS maps are simple. Start with a basemap and mash it up with your own data layers or those from other ArcGIS users. Then add tools that support what you want your users to do with your map: tell stories, perform analytical studies, collect data in the field, or monitor and manage operations.
Virtually anything you do with GIS can be shared using maps. And they can go anywhere. GIS maps work online and on any smartphone, and along with your supporting GIS work, they are accessible anytime.
Anyone can make, share, and use web maps. You can start by going through a short example. Suppose you want to make a map that allows you to explore the food, architecture, and design destinations for San Diego.
Select a basemap and zoom into your area of interest.
Add your data layers and specify how each will be symbolized and portrayed.
Create pop-ups that enable users to explore features by clicking on them.
Save your map into your My Content folder with a good description and a thoughtful name.
Share your map as a story map or other configurable web app.
The idea of a digital map mashup—recombining various geographic layers—is one of the great force multipliers in modern cartography. This ability to easily share and repurpose digital content has allowed individuals to create far more ambitious maps than would be possible if they had to work in isolation or start from scratch. The rise of the map mashup expanded cartography, so that anyone could build upon the work of others. Most of the thousands of maps created and shared every day within ArcGIS are created this way—maps that build upon the data, labor, and insights of the larger community. This era of collaborative GIS has empowered everyday citizens to participate in mapping as never before.
In ArcGIS, map authors can readily access beautiful sets of professionally produced basemaps that provide the digital canvas on which to tell their stories. Each of the Esri basemaps has a theme or focus. Their range serves the need for almost any map type. Whether it’s terrain, oceans, roads, or another of the many themes, the right basemap complements your subject and provides the background information critical to establishing its geographic context (locations, features, and labels). Each of the ArcGIS basemaps contains highly accurate and up-to-date information, at multiple zoom levels covering geographic scales from detailed building footprints to the entire planet. Providing data at each level of detail, for all locations on the globe, takes a small army of cartographers and eats up terabytes of data. The good news is that each of us can benefit immediately from those efforts. Some of the most widely used basemaps, such as those seen here, rack up billions of views every week.
Basemaps seem simple and relatively unobtrusive—and this is precisely their purpose. They should provide locational context (the “stage”) for the content that is to be overlaid on them. Operational overlays carry the subject matter of the map and provide the purpose for making any map. A layer can be anything—emergency response incidents, your company’s monthly sales, life expectancy, the location of oil and gas wells, or live traffic conditions. Merging a great basemap with one or more operational layers forms the heart of the modern online map.
Some map authors are data creators interested in mapping their own data. Many other authors, however, need help finding operational layers; they know what they want to map but need guidance in finding the data to fully tell the story. Fortunately, ArcGIS provides access to an array of content to use in operational layers. The GIS community, including Esri, compiles and shares thousands of ready-to-use authoritative datasets in ArcGIS, covering everything from historical census data to environmental conditions derived from live sensor networks and stunning earth observations. And it’s all in the Living Atlas of the World. You will learn more about it in chapter 4. Finding mappable, interesting geographic layers has never been easier.
Blending together ready-to-use basemaps, operational layers, and statistical graphs into a live, dynamic map allows you to share geographic content in a simple and concise format.
Web maps work across multiple scales. Zoom in to see additional details and gain insight. Online maps provide continuous pan and zoom. They literally have no edges—you can pan anywhere and zoom in for greater detail. Even if you don’t have operational data for a particular area, the basemap will still provide reference.
Web maps are windows into a wealth of information. Click on a map location to “pop up” a report and explore the information behind it. Pop-ups help reach into the map for more detailed information that emerges on demand. A single window into a map can become a window into a world of related information, including charts, images, multimedia files, and analytics. The ability to link such a wide variety of content to the map has transformed how we think about maps. They’ve evolved from static containers of data to dynamic information vessels.
Your online maps are no longer static. They can be readily and immediately updated because your layers online can contain the latest, most accurate information. When your data changes, the maps that reference that layer are also updated.
Your maps can combine more than your own data. You can mash up your rich GIS data with information from other users—in fact, whatever is useful and relevant to your objectives from the entire world of GIS users.
The world is full of data, and maps help you make sense of it. There is a growing need to turn geographic data into compelling maps. People just want to create beautiful, interactive maps and infographics with live data, easily and with confidence. The smart mapping mission is to provide a kind of strong “cartographic artificial intelligence” that enables virtually anyone to visually analyze, create, and share professional- quality maps in just a few minutes, with minimal mapping knowledge or software skills.
Smart mapping is designed to give ArcGIS users the confidence and ability to quickly make maps that are visually pleasing and effective. Cartographic expertise is “baked” into ArcGIS, meaning it’s part of the fundamental user experience of using ArcGIS. The map results that you see in front of you are driven by the nature of the data itself, the kind of map you want to create, and the kind of story you want to tell.
By taking much of the guesswork out of all the settings and choices that you could conceivably tweak, your initial map results are cartographically appropriate and visually pleasing. You can always change things at will, which you’ll undoubtedly do as you gain more experience, but smart mapping gets you to something effective very quickly. You spend less time iterating and wrangling your maps into fulfilling your intention.
One of the critically important capabilities of smart mapping is the added ability to interactively explore your data layers—for example, you can explore the range of values for median household income within each block group in your map by interacting with the histogram of median income values. The ability to interact with the data behind each map layer provides deeper insights into the questions you are trying to answer.
Maps are interactive, rewarding experiences, and not just pretty pictures. The most valuable maps are information products that are visually interesting from the first time you see them. Yet they reward you with additional information as you explore and interact with the map. When you touch the map, it responds by giving you details about the things you touch—touch a store and it tells you this year’s sales to date with a chart of the previous three years’ sales.
Great maps don’t just happen automatically, though. You have to put a little bit of yourself into the effort, just like a great resume, which starts out as a template but requires your information—your data—as well as your interpretation to make it really sing. The data you are mapping won’t tell its story without your help. Once you see the patterns emerging in the map, you can start emphasizing what’s important, and de-emphasize everything else.
Try to always make “beautiful” maps. By that, we mean effective ones that are clear on first opening but that also engage users of all levels to drill in, explore, interrogate, and learn.
Start with the final result you have in mind and work backward. To paraphrase Roger Tomlinson, one of the fathers of GIS in the 1960s, you’ve got to know what you want to get out of a GIS to know what to put into it. Clicking aimlessly leads to no clear resolution. Have a clear idea of the story you want to tell about your data. Then get some test data and go for it.Make a Better Map: How to map counts and percents together
ArcGIS Pro provides capabilities that enable serious mapmakers to create truly excellent maps, including support for highly sophisticated mapping workflows employed by professional cartographers. It includes tools for rich data compilation, for importing data from a multitude of publication formats, and for integrating this data with your own data to create consistent, accurate, and beautiful cartographic products for both printed and online maps. ArcGIS Pro is the workhorse application for serious cartographic production in both 2D and 3D and is used daily by hundreds of thousands of GIS users worldwide. This modern application builds on the tradition of great mapping with such enhancements as advanced 3D scenes.
The swisstopo map seen below, with its characteristic drawing and text style evolved by generations of Swiss cartographers over the past century, is widely considered the benchmark for 3D topographical mapping on paper. Today the agency uses tools like ArcGIS Pro to achieve the same results with computers.
While great cartography obviously predates the advent of computers, the digital era has yielded incredible fruit when it comes to mapping in the third (vertical) and fourth (temporal) dimensions. ArcGIS Pro provides tools that allow modern spatial storytellers to extend their maps into 3D and 4D (aka time).
What makes a good map? How can you engage people with a map? How do you make a map that offers unexpected insights and captivating appeal? We have been working on something at Esri that we hope will answer these questions: Maps We Love.
Maps We Love is an ongoing project where you will see the best of what’s possible with ArcGIS. This is where you come for the inspiration, ideas, and information you need to turn your data into brilliant maps. We give you a behind-the-scenes look at important steps, plus resources (lots of links) so you can dig deeper into these topics. Maps We Love is designed to demystify mapmaking, to give you the confidence and assurance that you can make beautiful, effective maps.Explore more Maps We Love
In this lesson you’ll use the US Department of Defense’s recently released Theater History of Operations data to create an 11” x 17” wall map encompassing all bombing and ground attack missions carried out by the United States from 1966 to 1974 during the Vietnam War.
You’ll begin by downloading detailed country outlines from the Living Atlas. With over 3.1 million missions in the dataset, the challenge is to create a data visualization that is more of a macro view. Each mission is represented by a single, nearly transparent point, so that isolated missions are hardly visible, while areas of intensive saturation bombing are nearly opaque. Finally, you’ll add a column chart of total missions by month and additional map elements including annotations, a scale bar, and title to complete the final product.