Animating EMUs with ArcGIS Pro!

I recently took to ArcGIS Pro to visualize and analyze the EMU clusters. Having spent most of my Desktop analysis experience in ArcMap, I was both surprised and quite pleased with what I discovered. Here are a few handy tricks I learned which can greatly aid in understanding this vast dataset a little better!

As you probably already know, the EMU points are a multidimensional dataset that can be sliced in many ways, each of them offering a unique and valuable perspective on the data. One such way – and probably the most obvious – is to slice the data by depth, looking at all the EMUs that occupy the world’s oceans between two depth intervals. If we do this iteratively, we can give ourselves 100 different views of the data. Doing so allows us to visualize how the prevalence of each EMU grows or shrinks as we descend deeper into the water column!

ArcGIS Pro has a neat capability which allows exactly this. It’s called the range slider.

The range slider acts in a way that’s very similar to a definition query. The main distinction? It allows its users to sidestep the multiple button clicks required to do an incremental step up or down in the result returned by the query.

To enable a range for a particular dataset, first, double click on a layer from the Contents pane to expand its layer properties. Once there, click ‘Range’ to go to the respective pane and specify the field on which you want to enable the capability.

(Note: the range slider only works on numeric fields, so if you’re working with categorical data and wish to try ranges out on it, you’ll first have to create a new field as assign numeric values to them.)

Now, when you click on your layer which is range-enabled, the following tab appears on the ribbon interface. This allows you to further customize properties such as how many steps within the range to visualize at once, how quickly you’d like to step through the range span, and whether you’d like to view it on repeat or switch directions.

Alternatively, you can also use the vertical range slider that will appear on the right side of the map pane to achieve the same effect. Once you have this all set up, simply click the ‘Play All Steps’ button to animate to your heart’s content!

For more on the range slider and its full capabilities, see the help topic here:

Get started with the range slider—ArcGIS Pro | ArcGIS Desktop

To get started working with the full suite of EMU data yourself, check out the EMU open data portal here:

And, finally, I wouldn’t leave you without first sharing a simple visualization of what I’ve just described. Enjoy!

The animation above shows the range slider and EMU data in full action and was created by using a third party application for capturing GIFs. Beginning at surface level (0m), the animation illustrates 100 distinct variations in the EMUs as they change with depth, all the way down to 5500m below the surface.

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  1. Mike Wilburn says:

    It’s worth noting that the acronym ‘EMU’ stands for ‘Ecological Marine Units’. For more on this rich data layer, have a look at its homepage here: