Start by logging into ArcGIS.com. Once you’re in, the home screen will look slightly different depending on if you have a free account or a UCSC affiliated account. The important part, which is the same for both, is the top menu.
Start by click Content. If you haven’t created anything yet, this page will say “No Items Yet,” but eventually this is where all of your content will be listed, including maps, StoryMaps, and individual datasets. Once you have content here, you can access to set things like sharing preferences and to open it for editing.
Now click Map in the top menu. This takes you directly to the map viewer and pulls up a blank map to get you started. In the next section, we’ll look at how to get started building a map from scratch.
Take a look around the map viewer. You should see three important areas: the top menu, the map details panel on the left, and the map viewer window in the main part of the screen.
In the top menu, you have several important controls that affect the whole map. On the left are options to Add data to the map and change the Basemap. In the middle are options to save your map and share your map. On the far right is a search box that allows you to quickly zoom to specific locations. There are additional options in this menu that you can explore. If you have a UCSC account you’ll note still more options, such as Edit and Analysis.
Let’s start by adding some data to the map.
From the Add menu, select Add Layer from File if you already have a map data file you want to use (filetypes accepted are CSV, Shapefile, GeoJSON, and GPX). After you find you’re file and click Import Layer, you’ll need to give this dataset a name and then add at least one tag—it can be anything at all pertinent (I often simply use “History”). You can then add your data the map.
If you don’t have a data file of your own, you can select Browse Living Atlas Layers from the Add menu. You can scroll down and make a selection or use the search box to narrow things down to something you might be interested in. For instance, if you search “earthquakes,” you’ll see a number of options, including the dataset “Recent Earthquakes.” Click to learn more about the dataset and then click Add to Map to add this dataset.
The details panel on the left shows you the data layers that exist in your map (if this is not visible or covered by another menu, you can click Details in the top menu and then Content to bring it back). You can add multiple data layers to your map, check and uncheck to make them visible or hide them, and drag them up and down to reorder how they appear on the map.
Deciding how to display your map data is important both for how you analyze that data and for how your present it to others. Styling is done layer by layer.
To change your basemap, select Basemap in the top menu and make a selection. There are further controls for the basemap below in the details pane.
For all other layers, controls are listed as icons beneath the layer’s name. Hover over the layer name to reveal these icons. The first option on the far left shows that layer’s legend. Next to that is an option to show the data table for that layer. Next to that is the option to Change Style.
Click Change Style. You’ll see two steps here. The first is to decide what attributes from your data you want to visualize. This could simply be the location itself. For that select “Show location only.” But if you have columns in the dataset that directly meaningful to your research question, then you can select one of those from the list. For instance, if you have a dataset of cities, and for each of those cities you want to show the overall population, if you have that figure in your dataset you can select it here. Same goes for a dataset on earthquakes—if you want to visualize the magnitude, select the appropriate column here. Note that you can only make one selection at a time.
Once you’ve chosen the attribute you want to show, under “Select a drawing style” you should see a few options that ArcGIS has determined might be appropriate for the kind of data you have. If you’ve selected “Show location only,” you’ll probably only have two options, a single symbol or a heatmap. If you’ve selected numerical data, you should have additional options such as showing values by color or size. To take the earthquake data example, if you selected “Counts and Amounts (Size),” the points would be displayed at different sizes based on the magnitude of the earthquake. The same would go for a dataset of cities with the population column selected.
When you select one of the style options, the map should automatically update with that style. You can then click “Options” for style to make further adjustments. Please remember to click OK (if you’ve gone into Options) and then Done when you are finished with your styling choice—if you don’t, the changes you’ve made won’t be saved. You can always go back and make further changes to the style by selecting the Change Style icon again for that layer.
A Few Styling Tips
As you can see, ArcGIS Online makes styling your data relatively simple. But there is still plenty of thinking on your part that is needed to make a map that both makes sense and is highly legible to viewers. Here a few things to consider:
– Make sure the style you’ve chosen for your data communicates the main point you want to make with that data.
– Consider you color choices. At a basic level, make sure they are legible to you, in particular that the color/s you use for your data is visible against your choice of basemap. Even better would be to consider accessibility by using a great color selection tool like ColorBrewer.
– If you are including more than one data layer, in addition to the basemap, be sure that the layers don’t compete with each other. If they do overlap in a way that is difficult to view together, consider leaving only one initially visible and allowing users to check and uncheck others to view them individually.
Unlike ESRI’s other mapping service StoryMaps, ArcGIS Online does not autosave your maps. So it is very important that you select Save frequently, and certainly before you exit a map you’ve been working on. The first time you save the map, you’ll have the opportunity to give it a name and some additional information.
When you are ready to share your map with others, first make sure the map is saved, then select Share from the top menu. You’ll first want to check who you want to share it with. If you have a free account, your choices will be between private and “Everyone.” If you have a UCSC account, you can choose between “Everyone” and “UC Santa Cruz” (which will make the map viewable only by others who have UCSC ArcGIS Online accounts).
You can then decide how to share the map. The two most commonly used options are sharing the link to the map or embedding the map on another website. For the latter option, simply click “Embed in Website,” adjust your settings, and then copy the HTML embed code. You can paste this code on another site you have access much as you would paste the embed code for a YouTube video.
In addition to importing datasets into a map, you can add points to a map using the Map Notes feature. Access this option by click Add > Add Map Notes. Name your new notes layer and then click Create. The left hand pane will show a wide range of symbol options. Simply select the symbol you want, click on the map where you want to add the feature, and then input information about that feature. You can then add more of the same symbol or select a different symbol to add. You can click symbols you’ve already added to edit their information or delete them. Click and drag to move added symbols.
If you want your basemap to be something other than the set offered by ArcGIS, there are a few ways you can do this. You can remove the basemap layer itself and use one of your own data layers as a basemap. This can make sense if you have a layer that has an appropriate amount of coverage, such as a dataset of country boundaries.
Another option—which we’ll focus on here—is to add a layer from another source. Let’s say you want to add a historic map as your basemap. Stanford University’s David Rumsey Map Collection is a great source for this kind of data. Not only does it have thousands of scanned historic maps, many of these have been georectified, which means they are ready to load into a digital map app like ArcGIS. We’ll practice loading one of these maps using the collection’s app services feature.
First, find a georeferenced map in the David Rumsey Map Collection that you want to import.
When you’ve found a map, click ‘This Map’ at the top of the screen to see more information about the map.
In the box labelled “Use in GIS apps” (just below the map preview image), click “Get Links.” Then copy the XYZ link.
In ArcGIS Online, click Add > Add Layer from Web. For type of data, select A Tile Layer.
Paste the XYZ link you just copied in the URL field. To use this as the basemap for the entire map, check the box “Use a Basemap.” If the map is of a more discrete location, such as a city or a region, you might want to use the layer on top of another basemap. Add the map's title and credit information. Then click Add Layer.
The layer should load in your map (you may need to zoom in on the map location and hide and then unhide the layer for it to load). If it a normal layer, and not the base layer, you can drag to reorder it as you would with any other data layer.
Editing Datasets (requires UCSC account)
To edit a dataset you’ve loaded into your map, click Edit in the top menu. You can then click an individual feature in the dataset and either delete it or edit its attribute data. Additionally, you can select New Feature in the left hand pane and click on the map to add a new feature to the dataset, including attribute data for that new point. Use the Undo and Redo buttons at the bottom of the pane if necessary.
Analysis (requires UCSC account)
With a UCSC account, you can also perform a large number of transformations and analyses on your data. When you select Analysis in the top menu, the left hand pane will display a little of categories that you can explore. Individual analysis options have an information icon to their right that provides an explanation of what that particular function does. Some functions transformation one or more datasets by joining them together, aggregating features within them, or summarizing their characteristics. Others do more advanced analyses such as identifying statistical clusters or calculating density of features. These analyses require at least one input dataset, sometimes more than one, and usually output a new dataset that will be automatically added to your map. Your exiting dataset layer should not be altered by these functions.