3.5-minute read

If you’ve not had much mental bandwidth left to ferret out non-COVID-19 news, we totally empathize. In case you missed the story of the third mass bleaching event in five years of Australia’s Great Barrier Reef, here’s a quick what’s what—along with a roundup of some inventive strategies aimed at keeping all of the world’s precious corals out of hot water.

Although some of the creature components of the natural world are currently experiencing a welcome period of rest and recovery, as a result of rising ocean temperatures, the large colonies of thousands of tiny animals that make up coral reefs are facing unprecedented heat stress that is exceeding their ability to adapt and survive. These architecturally complex living structures support beautifully biodiverse undersea communities that encompass up to 25 percent of all marine species, including 4000 types of fish and an estimated 8 million yet-to-be-discovered organisms. As critical parts of our planetary infrastructure, coral reef ecosystems contribute to the livelihoods of 500 million people in 100 countries, adding approximately 30 billion dollars to annual GDP.

Under normal environmental conditions, corals can live forever. Sadly, recurring and prolonged bleaching events caused by changes in water temperature and acidity as a result of oceans absorbing increasing levels of greenhouse gases (GHG’s) from the atmosphere have pushed corals beyond their comfort zone. During a bleaching event, stressed corals expel the symbiotic algae (zooxanthellae) embedded in their tissues, which they rely on for nutrition and which give them their often vibrant color. Without a consistent source of nourishment from their algal occupants, bleached corals slowly become weakened and may die, causing a chain reaction of equally adverse impacts for reef inhabitants. Depending on the amount of damage that occurs during a bleaching event, it can take decades for a coral reef to recover. To date, up to half of the world’s reefs have been severely damaged.

Okay, what’s the good news, you ask? Is there good news? Because we could use more of that. It’s undeniable that earth systems wait for no one, and our oceans have already been committed to a certain degree of warming. Now, one of the most important things we can do to create good news for corals and other marine wildlife is to help prevent bleaching events by reducing the GHG emissions that absorb radiation from the sun and raise ocean temperatures. As we sprint to ramp up mitigation efforts, scientists around the world from biologists to chemists to geophysicists are tackling the coral crisis from a few different angles in hope of changing the current trajectory from despair to repair. Here are some highlights from projects focused on saving our reef ecosystems from extinction:

Brightening Marine Clouds:
Earth scientists are geoengineering cloud parasols for the planet to cool waters around reefs and buy more time for corals. Through a process called marine cloud brightening, clouds are seeded with salt crystals to increase their reflectivity. These artificially enhanced bright clouds reflect solar radiation away from the earth lowering ocean temperatures in targeted reef areas. In late March, researchers at Southern Cross University in Australia conducted the first successful, small-scale cloud brightening experiment over a portion of the Great Barrier Reef. You can watch how they did it here.

Printing 3-D Bionic Corals:
Figuring out the symbiotic relationship between corals and algae will be critical for reef conservation in a warming world. To gain a better understanding of why corals expel algae under stress, bioengineers at the University of Cambridge have created bionic corals that can mimic the behavior of different coral species using biological materials and specialized 3-D printers. The Cambridge researchers also plan to construct large-scale colonies of man-made corals to grow algae for carbon capture and storage.

Breeding Climate Resilient Super Corals:
To create more resilient reef systems in anticipation of future warming, scientists at the Gates Coral Lab Hawaii Institute of Marine Biology are giving nature a helping hand through the breeding of corals that have successfully adapted to environmental stressors. By selecting the hardiest corals for reproduction and replicating various conditions of acidification, pollution, and temperature over time, marine biologists hope to grow more highly stress-tolerant super corals for use in reef restoration. You can learn more about these forward-thinking cultivators of corals in Coral Whisperers: Scientists on the Brink by Irus Braverman.

If you’re concerned about coral reefs and would like to keep tabs on how they’re holding up in near real-time, there are NOAA satellites for that at Coral Reef Watch.

You can also dive in and participate in some armchair ocean conservation by playing NeMO-Net, a new video game that helps train a NASA supercomputer to map the world’s corals.

If you’d like to follow a collaborative community of earth scientists working to maintain the healthy functioning of our planet, check out EarthCube.

And because gazing at marine life is good for you, to help tide you over until you’re free to roam, the Ocean Conservancy has coral reef wallpaper for your phone and desktop. Download away!

As always, hang in, stay safe, and be well!