Getting to Know ArcGIS Pro 2.6. Michael Law

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      Governments are opening access to data at an unprecedented rate. The open data movement provides agencies and the public with authoritative data and enables all levels of government to develop new tools and applications. Typically, only highly sensitive data is safeguarded or copyrighted anymore. Open data provides a way for people to extract information when they need it. It allows citizens, organizations, and governments to get right to problem solving, rather than spending a great deal of valuable time searching for and requesting data. ArcGIS® Open Data, an ArcGIS Online solution, allows an organization to host the data it collects so that the public can freely view interactive maps and search for and download data.

      Figure 1.3. Governments and organizations share open data through online portals. Michigan Open Data Portal (http://data.michigan.gov).

      GIS in the world: Fire prevention

      The City of Surrey Fire Service in British Columbia, Canada, focuses on fire-reduction education programs to increase prevention and awareness and create safer communities. The agency used GIS to identify areas of the city that met the requirements of being at high risk. GIS allowed the city to prepare a strategy of targeting education to reduce home fires. Read more about the project, “Preventing Home Fires before They Start,” at www.esri.com/esri-news/arcnews/winter1314articles/preventing-home-fires-before-they-start.

      Figure 1.4. Residential fire incidents in the City of Surrey for a six-year period. Courtesy of the City of Surrey.

      Basic GIS principles and concepts

      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.

      Figure 1.5. Map of Abu Dhabi showing building footprints, points of interest, roads, green space, and water features. Map courtesy of Municipality of Abu Dhabi City.

      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.

      Figure 1.6. Map of the Ogallala Aquifer showing a surface that represents the saturated thickness, water-level change, and projected usable lifetime of the aquifer. Map courtesy of Center for Geospatial Technology.

      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.

      Figure 1.7. A map with parcels, water lines, and valves. Attributes of the valve features include maintenance dates and information about valve type, size, usage, cover, lid type, and condition.

      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.

      Figure 1.8. Map of Portland, Oregon, showing net migration or deaths per acre because of “senior shedding” or out-migration. The red isolines identify concentrated areas in which mothers age 30 and over gave birth. Map courtesy of Portland State University.

      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, СКАЧАТЬ