Inside the daring plan to map every coral reef from space

Coral reefs are the rain forests of the ocean. They are beacons of biodiversity that is a quarter of the world and provide food and livelihoods to more than half a billion people worldwide.

But these aquatic havens now face existential threats: overfishing, coastal development, and heat stress. If humankind's actions continue to warm Earth more than two degrees Celsius (3.6 degrees Fahrenheit) above preindustrial levels, coral reefs as we know them could almost completely vanish. Seeking this impending crisis, the need to monitor them has intensified. But coral researchers face a mammoth problem: They do not know where all of Earth's reefs are, and only a small fraction of those are actively monitored. How can conservationists protect what they can not locate?

Now, researchers are using data from Planet Labs, which operates the world's largest fleet of Earth-observing satellites, to make the first global, high-resolution map of all coral reefs-a project called the Allen Coral Atlas.

The atlas is coming together with urgency. On Monday at the Our Ocean conference in Bali, Indonesia, the team behind the atlas unveiled a global photomosaic of Earth's coral reefs, with a resolution of about 12 feet per pixel-far more detailed than existing global coral maps. They have also released the first detailed maps of five coral reefs, where they are testing automated processes for classifying the satellite images.

The goal is that sometime next year, the team's algorithms would be able to identify and map out regions that would be possible. And by the end of 2020, I would like to provide a baseline for monitoring bleaching events and other short-term changes.

Paul Allen, who co-founded and philanthropist Paul Allen, who funded its creation, and Hawai'i Institute of Marine Biology Ruth Gates, one of the project's lead scientists. Allen died suddenly on October 15 from non-Hodgkin lymphoma, and died on October 26 from brain cancer.

"Ruth Gates was one of the world's most visionary, passionate and committed voices for science, conservation and coral reefs," said Andrew Zolli, vice president of global impact initiatives at Planet Labs, in an email. "Her spirit animated our shared work from the outset … Even in grief, we are energized by her example and her fierce urgency, and doubly committed to seeing her vision realized."

So, too, with Allen. "Paul," says Lauren Kickham, a senior program officer for Vulcan, the company that oversees Allen's business and philanthropic ventures.

An experienced technologist and passionate philanthropist, Allen's mantra can be fast moving and fix things. Allen regularly tasked his staff with lofty, relentlessly impact-driven goals, such as counting every single elephant on the African savanna or tracking illegal fishing from space.

Allen-an SCUBA avid diver-was already funding coral research, but its concern intensified in 2017 when Allen found his favorite reveve sites sickened and bleached. "He was lamenting that some of us were not doing so well. And then he looked at me and said something funny, like: 'In fact, your job should be to save the world's coral reefs,' "says Art Min, Vulcan's vice president of impact. "And I was like, 'OK, challenge accepted!'"

Gates, whose research Allen funded, helped bring together the project's brain trust. In the summer of 2017, Gates puts Zolli. The peer made them know the same researchers at the Carnegie Institution for Science and invited them to join the project. In short order, the University of Queensland, too, came on board.

"It's a little bit like the world wanted this to happen," says Zolli, a National Geographic Emerging Explorer trainer. "Suddenly, we had the makings of a dream team."

The team's audacious mapping plan starts with Planet Labs' more than 150 Earth-observing satellites, the largest fleet of its kind ever launched into space. Most of these tiny satellites orbit around the planet's poles. As earth rotates beneath them, the fleet acts like a scanner, capturing images of the planet's surface strip by strip. Every day, they photograph Earth's entire surface in perfect detail, with just 12 feet per pixel.

To make Planet Labs' raw images, more suitable for coral mapping, the Allen Coral Atlas brought on ecologist Greg Asner of the Carnegie Institution for Science. For months, Asner's team has worked with Planet Labs to computationally strip the images of visual elements that obscure the reefs: the atmosphere, the clouds, the sun's reflection, and the seawater itself. Asner's team also had to make sure that Planet Labs' satellites passed over the same coral reef, they got the same measurements-a crucial, and difficult, calibration.

"Planet of the world, we had 132 different Planet satellites pass over, and it hit me like, 'Oh my god!'" Asner says. "How do you make 132 different satellites behave?"

Once Asher's team and Planet Labs clean up the images, they pass the photographs at the University of Queensland. There are two coral, rock, algae, sand, or other materials algorithms. Phinn notes that satellite monitoring of the oceans has lagged behind the earth, and the massive satellite networks needed for this mapping project. "It's just mind-blowing that we're able to do this," Phinn says.

So far, Phinn and Roelfsema's team has been tested in the world. Now, the team needs to verify these maps in the field. They're also working with local conservation groups to make sure the Allen Coral Atlas will be useful for their work.

Take Blue Resources Trust, a marine conservation non-profit in Sri Lanka, for example. Nishan Perera, the trust's co-founder, says that the new data could help Sri Lanka craft marine protected areas and conduct better-targeted reef surveys. "The Coral Atlas really takes it to another level," Perera says. "It helps you to focus your work and maximize your resources."

Gates was initially tapped to lead this audit and outreach effort, but in June 2018, she told her colleagues about her cancer diagnosis. Gates asked her friend and colleague Helen Fox, Senior Director at the National Geographic Society, to step in and help. The two had been close since 2003, when they met at the Hawai'i Institute of Marine Biology.

"She used to say, 'If you're not having fun, why do it ?,' which to me is amazing," said Fox in an email. I hope the Allen Coral will prosper and achieve its best to improve management and help save coral reefs. Nothing would be a better way to honor the amazing legacy of Dr. Ruth Gates. "

Once the Allen Coral Atlas has mapped Earth's reefs, its goal will be to monitor these reefs for flashes of short-term change, acting as a global coral alarm system.

The idea is to scan Planet Labs' images for sudden changes in brightness within the pixels that correspond to live coral reefs. If a patch of coral quickly lightens, the coral may have bleached, or perhaps blast fishing has shattered a reef and exposed the corals' white skeletons. If corals quickly darken, it can be a sign of algae, or growing over the corals themselves or blooming in the water nearby.

Asner, the Carnegie ecologist, says that the world's races to lower its carbon footprint, the Allen Coral could not help but find that they are key to the climate change's slants and arrows: "Those are key, not just because they" The goal of this project is to be more sensitive, but it is more likely that the future genetic research will be successful.

In the meantime, the team is racing forward, honored by Paul Allen's and Ruth Gates's legacies.

"Ruth and I shared a deep wonder for coral reefs," said Asner in an email. "We laughed a lot. I'm going to miss her dearly. "

"It's an astounding group of individuals and institutions … and that brings a lot of hope," adds Kickham, the Vulcan program officer. "We've got all the tools we need to make this possible. So bring it on. "