Mapping is an excellent way to gain insights that aren’t readily available through other forms of analysis, and many of the datasets on Enigma Public contain coordinates you can map. To get an idea of what’s available, try searching the “Metadata only” for latitude longitude.

Most of the resulting datasets include information you can map (if a dataset has no “hits” listed, this usually means there are columns labeled “latitude” and “longitude”). If you open one of the datasets and click the Fields tab, you can scroll through the field names to confirm.

Mapping nuclear power stations and toxic release data

In this example, we’ll use CARTO to map two Enigma datasets. The datasets we’ll use are:

Both datasets include location information in a format you can map using CARTO. Here’s an example from the Nuclear Reactors database.

Downloading the datasets

To map the datasets in CARTO, you’ll need to begin by exporting the data from Enigma Public. For each of the two datasets:

  1. Use the link above to open the dataset in the Enigma Public Data Viewer.
  2. Click the Export button to download the dataset to your computer.

You should now have the two CSV files you need.

Uploading the data to CARTO

If you don’t already have an account on CARTO, sign up for a free account at When you have your account, sign in and follow the steps below.

  1. Click Maps near the top left of the CARTO window and choose Your datasets from the menu.
  2. Click the NEW DATASET button at the top right of the screen.
  3. On the CONNECT DATASET tab, use the BROWSE button to add the “Nuclear Reactors” dataset, or drag it to the “drag & drop” area. Then click CONNECT DATASET.
  4. When the dataset is displayed, click CREATE MAP at the bottom right of the screen. Then click EDIT YOUR MAP. You’ll see a dot marking the location of each nuclear reactor represented in the dataset.
  5. In the left panel, click the dataset and then click STYLE LAYER.
  6. Increase the FILL size to 20 and change the color you something that contrasts with the default color (for example, blue).

Now that you have the nuclear reactors marked on your map, add the toxic release data as follows:

  1. Click the Back arrow beside the dataset name to return to the LAYERS panel.
  2. Click the ADD button and then click CONNECT DATASET.
  3. On the CONNECT DATASET tab, use the BROWSE button to add the “Toxic Release” dataset, or drag it to the “drag & drop” area. Then click ADD LAYER.

Now that you have the two datasets represented as layers on the map, you can begin exploring.

Looking for relationships

With the two datasets represented on the map, zoom in to explore a region of interest. For example, you might be interested in the southeastern United States.

You can now look for releases (in yellow) that coincide with nuclear reactor sites (in blue). However, you won’t yet get any information about any site. You can fix that as follows:

  1. In the left panel, click the Nuclear Reactors dataset (the one with the green ‘A’ button above).
  2. Click STYLE LAYER if prompted, and then click the POPUP tab.
  3. Under Style, click the LIGHT button.
  4. Under Show items, select owner and facility.
  5. Click the Back arrow beside the dataset name and do the same for the “Toxic Release” dataset (the one with the red ‘B’ button above). This time select parent_company_name, unit_of_measure, chemical, facility_name, and total_releases.

Now go to the map and click on any toxic release marker that’s located within a nuclear reactor marker. The examples below indicates that, according to the data, 13,433 pounds of nickel compounds was released from the Crystal River Power Plant, and 20,000 pounds of methyl methacrylate was released from Southern Nuclear Plant Wilson/Vogtle.


A single dataset can yield a lot of interesting information, but when you combine two datasets, you can gain insights that aren’t available otherwise. Mapping is a great way to combine two datasets that include location information, and CARTO is an excellent tool to use to do this.