What is ESDR?

ESDR stands for the Environmental Sensor Data Repository, which is a server created by the Carnegie Mellon CREATE Lab that retrieves live time environmental sensor data from many different sources, from EPA air quality monitors across the United States to home sensors that are connected directly to the repository.

The ESDR Explorer helps to organize and visualize all of these sensors so that they are searchable and explorable.

Link to the ESDR Explorer tool: esdr.cmucreatelab.org/browse

Link to find where to upload your own sensors: esdr.cmucreatelab.org

How to use the ESDR Explorer:

When you first arrive:

You will notice the different areas of the website that have different functionalities to explore and look for sensors:

The Map Area:

Each blue dot represents a channel or group of environmental sensors located in that area. Clicking on a dot will open up a menu screen with checkboxes to show all the sensors associated with that dot:

By checking one of the checkboxes that appear, a graph is opened up at the bottom of the website displaying the data that exists for that sensor and a black outline will appear around the sensor. The graph that is opened up is displayed in the timeline area.

The Timeline Area:

The timeline area is located underneath the map.


The top of the timeline area has a timeline bar that lets you zoom in and out of any time range. You can drag on the timeline left and right to shift the time range, and you can scroll or two finger pinch on touchscreen devices to hone in on a smaller or larger region of time. You will notice that no data exists in this time range for the above image, so it may be necessary to zoom out to see where data does exist and then zoom into a desirable viewing range:

You can also use the Timeline Tools to easily manipulate the zoom timeline area. From left to right:

Opening up multiple channels will let you compare sensor data trends.

To delete a timeline, hit the small x button in the top left of each timeline:


The Channels Area:

The channels area displays the entire list of environmental sensors that exists in the repository and allows you to search for and filter the results. By typing into the search bar for a name or part of a name of a channel, the list at the bottom shortens and the dots on the map change to show the result of the search. You can further refine the search by hitting one of the search result filters, such as filtering the list for PM2.5 or Ozone, which will reduce the list to include every type of sensor checked. Not all channels are categorized by type, so the filter may hide a channel that shouldn’t be.

Hit the Clear Search Filters button to reset the map to show all nodes.

The Visualization Area:

This area allows helps to visualize air quality across the sensors for PM2.5 and PM10. You can start the visualization by pressing either the PM2.5 or PM10 buttons in the dark grey box and the dots on screen will color based on the legend that appears on the right. You can then drag on the timeline where the red cursor appears and watch as the colors change over time. By hitting the play button, the cursor will move across the timeline and its speed can be varied by changing the Loop Duration value (in seconds). You can have the timeline loop by pressing the Loop button. You can turn off the visualization by hitting the “None” button.

Finally, the Export Data button can be used to download a .csv (comma separated data, can be opened in Mi
crosoft Excel) or .json (can be converted directly into a Javascript object using Ajax) file of the data that is currently displayed on the timeline. You can download that data by pressing the “Download Link” link.