Harnessing GIS: Getting the Most from Esri's Free Online GIS
Professional Surveyor Magazine - April 2012
by Ray Carnes
Recently, I was talking to a group of California land surveyors when one of them asked me if there was an easy way for him to make a map from his spreadsheet that listed all the lat/longs of the projects he had done. He didn’t have any mapping software and wanted something very easy to use. It seemed like such a great question, I decided to share the answer with all of you.
For about three and a half years, Esri
has been building ArcGIS Online, a GIS hosted “in the cloud” that allows anyone with a web browser to create, share, and make changes to maps (and in some cases, download the data). As surveyors, you can use this service to check out a variety of data sources (USGS quads, PLSS, satellite and aerial imagery, NGS control, local benchmarks, digital plats, parcels, zoning, soils, landslide susceptibility, and more) before you head out to do your next survey. You can make a private map, email someone the link, and have them draw on it and let you know you should take a look at their changes. You can even upload your own data and embed the map on your own website.
Using Existing Maps
Point your web browser at www.arcgis.com
to see what ArcGIS Online has to offer. There are hundreds of thousands of maps that have been shared from government agencies, local governments, and private companies. Just type a keyword in the box at the top of the website.
Try any of these keywords to see some interesting maps: plat, parcel, survey, control, zoning. Once you get the hang of it, try your own search terms. When you find a map you want to see, click the Open link under the map thumbnail.
Creating Your Own Map
You can create your own map very easily. To save it you need to register with Esri. It is free and gives you 2GB of space for your maps and data uploads. Click Sign In
in the top right corner and then Create an account
on the page that comes up.
Once you have created your account, click the MAP
button at the top of the window. You will see that all it takes is four easy steps to make your map.
Step one involves panning and zooming: use your mouse and scroll wheel, the arrow keys on your keyboard, or the zoom slider on the left of the map. To zoom in, you can also hold down the shift key and drag a box on the map. Click the arrow in the top right corner to open an overview map.
Use the search box in the top right corner of the map to find locations such as place names, addresses, intersections, cities, points of interest, and geographic features. The map is automatically zoomed to the closest match from your search, and a callout marker is added (you can remove this by clicking the X in the upper right corner of the marker.)
You can create bookmarks on the map if you have several places you want to be able to navigate to more quickly. When you click a bookmark, the map is repositioned at the location and scaled to where it was when the bookmark was created. To create a bookmark, click the Bookmark
s button. To open the Bookmarks drop-down list, click Add Bookmark
and enter a name for the bookmark. The bookmark is added to the Bookmarks drop-down list. Click the Close
button to close the drop-down list.
Step two involves picking a basemap and deciding what other layers you want to add to the map. Select a basemap by clicking the Basemap
button and clicking on a specific basemap. You have a variety of choices including imagery, streets, topography, and shaded relief. To see information about one of the basemaps, click the basemap to add it to your map, click the Details
button, click the Show Content
button, then click the arrow to the right of the basemap name. Click Description
to see information about the basemap.
Once you have a basemap that you like, click the Add
button to see the four options you have for displaying content on top of the basemap. Search for Layers
is much the same as the searching you did before for maps, but this time for layers that you can add to your own map. Editable Layer
allows you to give yourself and others the ability to mark up the map and save Map Notes with the map. Add Layer from File
is where you can upload shapefiles, CSV/TXT files, and GPX files (the GPS exchange XML format).
Remember I mentioned uploading a spreadsheet of project locations? This is where you would do that. Make sure the columns with the lat/long coordinates are called lat, long; or latitude, longitude; or y, x. Any other columns (project details) will automatically appear in a popup when you click on the point.
When it comes time to choose how to display your data, you can choose from several hundred symbols in 10 categories and even supply your own symbols in JPG, GIF, or PNG format.
Add Layer from Web
is where you point to KML or CSV files hosted on a website. If you are really adventurous, you can also use this option to load a different basemap than the ones Esri provides.
Don’t forget to save your map when you are done!
If you added an editable layer to your map, you (or anyone else you share the map with) can easily mark it up. An Edit
button will appear on any map that you can edit. The Add Features
dialog will appear, allowing you to click on the kind of feature you want to add to the map.
Because you don’t have control over datum transformations with ArcGIS Online, the maps won’t be super-accurate, and you might find your data shift slightly from the precise locations you have collected. However, the shift will be in the range of the precision of the basemaps, about 1:10,000.
Embedding Your Map in Your Website
If you want to link or embed your map in a website, you must share your map with everyone. If you have your map open, click the Share
button. (If you don’t have your map open, click MY CONTENT
, check the box next to the map you want to share, and click the Share
button.) Once you check the box next to Everyone you will see that the Embed in Website
button becomes active. Check the size and options you want and copy and paste the code into one of your own web pages!
If you don’t have your own website, you can click Back
, then Make a Web Application
, and choose a template, and Esri will host it for you.
Sharing Your Map via Email
Once you have shared your map, you can get a shortened URL via the Share
button in the box where it reads Link to this map
. Email the URL—which points to your map—so others can view it, edit it, and even make their own map by building on yours.
Over 1,000 maps show up when you search on the term “survey.” Spend some time looking at a few of these and you will find examples of ArcGIS Online being put to some creative uses. Your colleagues are making maps of their chapter meetings to embed in their own websites. They are uploading survey control and benchmark data, as well as the projects they have worked on. They are harnessing GIS and making it work for them!
There are many other capabilities available with ArcGIS Online, so once you get comfortable with it, make sure you try scanning the help to learn more. You can create groups and invite others if you want to share maps among fewer people. Even better, visit www.esri.com/software/arcgis/arcgisonline/features/personal-use.html
to learn more and access over a dozen video demos showing everything I mentioned.
Remember, if you have anything you’d like to ask me about this article or anything else related to GIS technology for CAD users, I can be reached at email@example.com
. Be sure to email me if you’d like me to outline how you would do the same thing with ArcGIS Desktop (ArcView or ArcEditor).
Ray Carnes stumbled across GIS in 1992 and has used it ever since for managing data, modeling and analyzing geographic features and helping users understand how it helps them make better decisions. He has spent nearly 20 years (10 with Esri) providing GIS and IT technical support, training, implementation, and development services.
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