You can visualize data in a GIS as layers in a map. You can represent geographic and manufactured objects on the earth in a map by symbols: points, lines, and polygons. In the accompanying map, points represent trees and points of interest; lines represent roadways; and the polygons represent building footprints, green space, and water. Point, line, and polygon data is also called vector data. Features of the same type—such as trees, roadways, or buildings—are grouped together and displayed as layers on a map. To make a map, you add as many layers as you need to tell a story. If you are telling a story about a river that seasonally floods, you add a river layer and past flood hazard layers. You can also add a land-use layer to visualize what type of property, such as agricultural or residential, is affected by the flooded river. If you are building a city map, you start with a boundary layer, a street layer, and building footprints. By adding more layers, you can build a map that describes the city to your readers.
If you make a map of your house, a lake, or a city park, you might draw an outline to represent the outer boundary. But what about natural phenomena—such as temperature, elevation, precipitation, ocean currents, and wind speed—that have no real boundaries? Weather maps show blue areas for cold and red areas for hot. Wind speed can be represented using a range of colors. Or you can instead record and collect measured values for any location on the earth’s surface to form a digital surface, also known as a raster. Captured location data is recorded in a matrix of identically sized square cells at a specific resolution—for example, 15 square meters. In the accompanying example, an analysis of an aquifer uses different rasters to calculate a result showing saturated thickness and usable lifetime.
Features have locational data behind them. Features also contain attribute data, known as attributes. For a forestry map, point features that represent trees might include attributes such as tree species, height, bark thickness, and trunk diameter. For a utility map, lines that represent sewer pipes might include attributes such as flow rate, flow direction, pipe material, and length. Feature attribute information is stored in a table in a GIS database. Each feature occupies a row in the table, and an attribute field occupies a column. A GIS database can hold large collections of features and their corresponding attribute data. A GIS provides many tools for you to query, manipulate, and summarize large quantities of data.
Data can be queried and analyzed. In a GIS, you can perform a query on all the data that relates to phrases, terms, or features that you choose. For example, you might be looking for clusters of low-income neighborhoods to analyze poverty levels per square mile. Querying data from a database allows you to display only the data that relates to a certain theme. Additionally, a GIS enables you to identify spatial patterns in the data through the use of geospatial processing tools. What is the problem you are trying to solve, and where is it located? The accompanying map shows analysis and a complex pattern of senior citizen out-migration. Depending on your project, you can choose from among hundreds of analysis tools.
The ArcGIS® platform
ArcGIS Pro, part of the ArcGIS Desktop suite, is designed for GIS professionals to analyze, visualize, edit, and share maps in both 2D and 3D.
ArcGIS Desktop is part of the much larger ArcGIS platform, which also includes ArcGIS Online and ArcGIS Enterprise. Organizations can leverage the entire platform to share maps and apps with their end users.
ArcGIS includes ready-to-use spatial data and related GIS services, such as global basemaps, high-resolution imagery, demographic reports, lifestyle data, geocoding and routing, hosting, and much more.
Finally, the ArcGIS platform includes essential tools for developers to build web, mobile, and desktop apps.
ArcGIS® Pro
In this book you will learn how to use ArcGIS Pro and ArcGIS Online. Your work in ArcGIS Pro is organized into projects. These projects contain maps, layouts, layers, tables, tasks, tools, and connections to servers, databases, folders, and styles. Essentially, all the resources needed for a project are in one place. ArcGIS Pro can also connect to ArcGIS Online public content. And if you belong to an organization, you can share the content among your team. Projects are designed to be collaborative so that others can share and open them.
Maps and layouts display a project’s spatial data in either 2D maps or 3D scenes, or both simultaneously. You can create, view, and edit multiple maps, layouts, and scenes side by side, and even link them so that they can be panned and zoomed together. ArcGIS Pro uses ArcGIS Online basemaps, which provide a backdrop or frame of reference as you add your own layers.
A collection of geoprocessing tools allows you to perform spatial analysis and manage GIS data. Geoprocessing involves an operation that manipulates spatial data, such as creating a new dataset or adding a field to a table. You can combine tools in ModelBuilder™ to create a diagram or model of your spatial analysis or data management process. For advanced users, Python, the scripting language of ArcGIS, provides a way to write custom scripting functions to help automate ArcGIS workflows. In addition, tasks can be created and defined for organizational users who are required to follow specific workflow steps.
The ability to share your work is a central part of the ArcGIS platform. In ArcGIS Pro, you can share maps, layers, or entire projects. Sharing involves packaging components into a compressed file, which you can distribute to others within your organization or externally. You can store your package on a shared network drive or serve it across a website or mobile device.
To perform the exercises in this book, you need ArcGIS Pro installed on a computer that is running the Windows operating system, as well as an internet connection and an up-to-date web browser to access ArcGIS Online. Optionally, you might use a smartphone or tablet to access some of the ArcGIS apps that run on these devices.
Downloading exercise data
If you do not have an ArcGIS Online subscription, you can create a free ArcGIS Online trial account, which includes the authorization to use ArcGIS Pro. For more information about creating an ArcGIS Online trial account, go to www.esri.com/arcgis/trial.
The exercise data for this book is available for download from an ArcGIS Online group named GTK Pro 2.6, under the Learn ArcGIS organization, available at go.esri.com/GTKPro2.6Data.