Frequently Asked Questions & Support

Why did you do this?

Paul G. Allen was an avid diver, traveling the world to explore new areas and sea life. While planning a dive at one of his favorite reef diving spots, his team informed him that the reef had recently died and he should no longer dive there. As a technology leader and philanthropist, Mr. Allen assembled some of the best scientists, advocates and remote sensing technologists to build a tool that would do three things:

  • Improve global understanding of our coral ecosystems
  • Drive better policies to help protect them
  • Encourage others to take action

He knew that only by filling data gaps about existing coral would scientists, NGOs and lawmakers be able to make those necessary decisions to giving coral reefs a fighting chance.

The Allen Coral Atlas brings together partners from Planet, University of Queensland, Arizona State University's Center for Global Discovery and Conservation Science (GDCS) and National Geographic Society to take high resolution satellite imagery and advanced analytics to map and monitor the world’s coral reefs in unprecedented detail. The Atlas aims to provide a high-resolution, up-to-date global image of the world’s coral reefs, and detailed maps showing the composition and structure of five important reefs located throughout the world.

Why are only a few reefs mapped and not the whole world?

The initial phase, through October 2018, was a proof of concept. We decided to focus our resources on sites with a wealth of existing field data, and sites representing different coral reef types, geographies, and sizes. The purpose of this approach was to demonstrate that our methods could be applied to a wide range of coral reefs globally.

When will you map the reef(s) I work on (and the rest of the reefs around the world)?

By Summer 2021, we plan to have all the world's coral reefs mapped. To get to the global scale, we are mapping region by region. If your organization is interested in contributing to your location, please contact us at

What do I do if I find an error or problem in the map?

We welcome your feedback. As this is an evolutionary process, and the Allen Coral Atlas is in a beta stage, the maps may have issues… some of which we are aware of, others we’d love to have you report to us.

Please submit any identified errors with suggested corrections to including: Reef name(s); coordinates and/or a georeferenced polygon (in kml, shapefile, or JSON format); screen shots from the Atlas of relevant area (annotated with details), explanation of the error and your suggestion for correcting it/them; any relevant field data; your contact details.

The statistical summary for mapped classes say “Mapped area: 0 km sq”, but I know there is coral there!

You are likely looking at only the satellite image layer in one of the areas we have not yet mapped, and so there is no area calculated for existing reef. If you think you have found an error, please contact our support team at

Why did you combine coral/algae as a single mapped class in the benthic community maps?

In the satellite data currently being used for mapping, coral and the algal forms growing on reefs “look” highly similar and it is difficult to separate them, hence the combined class. The microscopic algae that lives inside the living coral has similar concentrations of chlorophyll-A that fleshy algae, growing on top of dead corals, has. This gives them similar spectral reflectance signatures, making them difficult, if not impossible, to differentiate with the technologies we are using for the Atlas project. We’re investigating routes to differentiate these in the future.

How do I access your API?

It is on our technology roadmap, but not yet accessible. We plan to make it available in summer 2020. If you have ideas for integrations with the Atlas or interface requests, please let us know at

Can I use the Atlas as a chart for navigation?

Please don’t! We wouldn’t want you to run aground.

Can I use the Atlas for planning my coral conservation work?

We’d be ecstatic if you used the Atlas for this, and we would love to hear about it. Send us your stories at

Are you going to map deep water or cold water corals?

At this time we are only mapping tropical shallow coral reefs, between 30 degrees North and South of the equator in depths shallower than 10m for benthic composition and up to 20m for geomorphic zonation. These limits are set to encompass most reefs consistently across the globe. The depth limitation is a physical limitation of the satellite image data and its ability to detect and measure reflected light from corals accurately below a certain depth. Practically, this means that with increasing turbidity of the water column and/or depth, reef features are harder to discriminate from each other.

I have maps and field data - can these be submitted and used in the Atlas?

Yes, we expect to be able to provide this capacity in future. All data submitted may not be published and will have to meet certain data and meta-data standards. Please contact us at submissions@allencoralatlas.orgabout implementing your data.

Allen Coral Atlas data licensing and guidance on citation

Data licensing

  • Allen Coral Atlas maps, bathymetry and map statistics are © 2020 Allen Coral Atlas Partnership and Vulcan, Inc. and licensed CC BY 4.0 (

  • The Satellite Coral Reef Mosaic is © 2020 Planet Labs and licensed CC BY-SA-NC 4.0 (

  • NOAA Coral Reef Watch has specific recommendations for Coral Reef Watch Data and Product Citation, described in more detail in our Science & Methods section.

  • Some other data on the Atlas website is copyright by the data providers (e.g., Open Street Map) and requires proper attribution if reused.


Allen Coral Atlas (2020). Imagery, maps and monitoring of the world's tropical coral reefs.

For more information on citation and attribution:

We would love to hear about any use of our data.  Please tell us about it at

Other citation suggestions for specific use cases:  

  • Universal Web Citation Format: Use the following general citation format for any Allen Coral Atlas resource accessed digitally through the Allen Coral Atlas website:
    Allen Coral Atlas (2020). Imagery, maps and monitoring of the world's tropical coral reefs. Zenodo. DOI:

  • Images: For images obtained from the Allen Coral Atlas website at, use the following citation: Image credit: Allen Coral Atlas.

  • Integrating our data into a website or other product via our API and WMS: When integrating our data, please cite the Allen Coral Atlas in a manner that is clear, accurate and easily discover-able and link to our website.  Please be sure that our Content is never displayed in the absence of such citation. 


Geomorphic zonation classes

Geomorphic zones (100's–1,000's m) are those areas on a reef with a unique set of benthic and substrate structures produced by a specific combination of water depth, wave and current strength. Common zones are inner and outer reef flat, reef rim and reef slope. Where benthic is considered living matter and substrate are non-living matter.

Benthic composition classes

Benthic community zones (10's–100's m) are those areas that form an assemblage of frequently co-occurring coral, algae, seagrass, rock, rubble and sand.

Please see the below definitions for many more technical and scientific components of the Atlas. 

Contact Us:

As mentioned, this is an evolutionary process. Do you have a question, comment, or feedback? Just want to get involved? Let’s connect! Contact us at