Getting to Know ArcGIS Pro 2.6. Michael Law
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What is a GIS?
Probably the most commonly asked question to those working in the geographic information system (GIS) field is also one of the most difficult to answer in just a few brief paragraphs: What is a GIS? A GIS is composed of five interacting parts that include hardware, software, data, procedures, and people. You are likely already familiar with the hardware—computers, smartphones, and tablets. The software consists of applications that help make maps. The data is information in the form of points, lines, and polygons that you see on a map. People, users like you, learn how to collect data using mobile devices and then make maps using the software and data on computers. As your knowledge of GIS grows, you will learn more about procedures and workflows to make maps for yourself or your organization. Decision-makers and others in an organization rely on GIS staff to maintain data and create insightful map products.
GIS has many facets. It captures, stores, and manages data. It allows you to visualize, question, analyze, and interpret the data to understand relationships, patterns, and trends. GIS can be used simply for mapping and cartography. You can use it on the web to view maps and collections of data. You can also use it to perform spatial analysis to derive information from multiple data sources. In any capacity, the results from a GIS can influence decisions. Organizations in almost every industry, no matter what size, benefit from GIS and realize its value.
Collecting spatial data—that is, information that represents real-world locations and the shapes of geographic features and the relationships between them—involves using coordinates and a suitable map projection to reference this data to the earth. For example, the distance that separates a conservation area and a neighborhood of a city is an example of a spatial relationship. How is wildlife in the conservation area affected by the increasing pressures of a growing urban setting? The spatial relationship between geographic features allows the comparison of different types of data.
When paired with attribute data—information about spatial data—a GIS becomes a powerful tool. For example, the location of a hospital is considered the spatial data (referenced to the earth). Information about the hospital, such as its name, number of rooms available, emergency rooms, specialization in medical procedures, patient capacity, and number of staff, is all considered attribute data. You can use this attribute information to maintain records in a hospital network. It allows people who have that information to perform spatial analysis—a technique that reveals patterns and trends—to answer the following types of questions: What are the average wait times for emergency visits to the hospital? Does the patient capacity efficiently serve the demographics of a given city area? Do certain medical conditions happen more frequently in the area, and is the hospital equipped to handle them? To answer these questions fully, you must compare the data and attempt to explain the patterns. A children’s hospital can integrate spatial analysis with population-based resource planning to propose children’s health-care initiatives. This integration can greatly increase the hospital’s ability to identify and allocate resources to better meet local health-care needs, providing timely access to care for children across a city or region.
GIS in the world: Cultural heritage and GIS
Cultural Site Research and Management and the University of Arkansas Department of Geosciences began a project more than 25 years ago to understand the accumulating effects of nature and foot traffic in the ancient city of Petra, Jordan, a stone city famously used as a backdrop in the movie Indiana Jones and the Last Crusade. GIS was used to create a database and model for use in archaeological research and land management and is currently used to automatically monitor and detect changes in the condition of historical sites in Petra. Read more about the project, “Cultural Heritage Management and GIS in Petra, Jordan,” at www.esri.com/news/arcnews/summer12articles/cultural-heritage-management-and-gis-in-petra-jordan.html.
GIS today
GIS has been helping people better understand their world since the 1960s. It provides a framework of practical means for transforming the world with all kinds of activities, from improving emergency response to understanding bird migration patterns. People are integrating GIS into how they work with data because it is a visual, quantitative, and analytic tool. It provides people with the structures and concepts to handle data systematically.
People today have unprecedented access to data and information. A growing system of connected networks allows people to easily access data, collaborate with others, and produce and share results from desktops, laptops, and mobile devices—essentially from anywhere. The current trend of connecting people who work in the office and in the field allows for real-time analysis. Decision-makers use operations dashboards to monitor real-time data feeds and other sources of information. For example, a GIS coordinator for a local government can track real-time emergencies and respond by coordinating fire, police, and ambulance resources.
GIS is pervasive, interactive, and social. Dynamic and interactive maps on the internet, known simply as web maps, are ideal for allowing many users to access and quickly locate features and visualize data. In the past, it took a team of GIS professionals to put together an online map. Now anyone can connect to ArcGIS® Online, make a map with a few layers and a basemap, and then share it with friends, coworkers, or anyone. The latest generation of web maps has simplified that process and now forms a platform that anyone can use.
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.
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.
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