Introduction to ArcGIS OnlineJeffrey Widener, GIS Librarian/Assistant Professor

(Updated: August 26, 2016)

DescriptionArcGIS Online is a collaborative web-based mapping application that enables users to store (some) data, analyze it, project it, share it, and publish it. ArcGIS Online has a suite of plug-and-play maps, and it also allows users to upload their own data to the ArcGIS system.

ESRI, the producers of ArcGIS Online and the ArcGIS mapping software, have three different levels of ArcGIS Online—a public account that is free and also freely available to people on the web, a 60-day free trial of ArcGIS Online, and an enterprise paid subscription service.

Today, you will establish and ArcGIS Online public account. You will download two earthquake datasets from the Oklahoma Geological Survey. You will upload these datasets into your online map. You will also learn how to symbolize the data points.

Part I1. Go to https://www.arcgis.com/home/.2. In the top right corner, click sign in. 3. At the sign in screen, select “create a public account.”4. Fill in your information and select create my account.5. Once you’re signed in, open a new web tab.

Note: you can go back in to your account profile later and give ESRI your home address. They have two publications that you’ll receive via snail mail—ArcGIS User and ArcNews. Both publications are rich resources for mapping and staying up to date.

Part II1. Go to www.ogs.ou.edu. 2. On the left side of the screen, click “Research,” “Earthquakes,” and “Catalogs.”

3. Click on the 2010 catalog. 4. Download the “2010.csv” file.5. Go back to the catalog list and download the “2015.csv” file in the 2015 catalog.6. Move these files out of your downloads folder and onto your desktop.

Note: go back to one of the catalogs and look at the list of files. Some of the file extensions will likely make no sense to you and that’s OK. A csv (comma separated values) file is often good enough to work in many mapping applications. The .kml file (Key Marked Language) is specific to Google Earth and other Google products.

Part III1. Go back to your ArcGIS Online page. Make sure that you’re still logged in.2. On the Menu bar at the top of the page, click on “Map.”

3. On the top left side of the screen is an “Add” menu. Select “Add Layer

from File.”

4. Either search for your 2010.csv file using the choose file button, or drag and drop the 2010.csv file into the window.5. Click “Import Layer.”6. Your 2010 earthquakes should now be showing on your map, and you should now have a populated “Change Style” window on the left side of your screen.7. Take some time to look at your options on your style screen. The “Choose an attribute to show” option contains the fields (or data column titles) in the CSV file. You typically need metadata to decipher what the fields mean, but these are somewhat intuitive. 8. The style likely defaulted to county. Switch the “attribute to show” to “pref_mag,” which is the magnitude/intensity (measured on the Richter scale) of the earthquake.9. Notice that the mapping application senses the data and gives you options for the drawing style. 10. Click on options in the“ Counts and Amounts Size” box. 11. Notice that pref_mag has negative numbers in it. These are unknown earthquake occurrences, meaning something set off the seismometer but it didn’t get a good recording. You could manually remove these from your CSV file, or clean up the data, which we’ll skip for now.12. Click the close triangle in the Change Style box.13. Click “Done” at the bottom of your Change Style box.14. Repeat the same steps for the 2015.csv file.15. Click on options in the“ Counts and Amounts Size” box. 16. Click on symbols and change the color of the 2015 earthquakes.17. Click OK and Done.18. Click on “Contents.”19. On the 2015 layer file, click the icon that looks like a table/chart. It’ll likely take some time, but on the lower portion of your map, you’ll have the CSV file visible. 20. How many earthquakes occurred in 2015?21. Find the same information for 2010.22. Take some time to play around with your data.