Sign up for our daily briefing

Make your busy days simpler with Axios AM/PM. Catch up on what's new and why it matters in just 5 minutes.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Denver news in your inbox

Catch up on the most important stories affecting your hometown with Axios Denver

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Des Moines news in your inbox

Catch up on the most important stories affecting your hometown with Axios Des Moines

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Minneapolis-St. Paul news in your inbox

Catch up on the most important stories affecting your hometown with Axios Twin Cities

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Tampa Bay news in your inbox

Catch up on the most important stories affecting your hometown with Axios Tampa Bay

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Charlotte news in your inbox

Catch up on the most important stories affecting your hometown with Axios Charlotte

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

A green sea turtle among the corals at Lady Elliot Island, the southernmost coral cay of Australia's Great Barrier Reef. Photo: Jonas Gratzer/LightRocket via Getty Images

Australia's Great Barrier Reef has lost over half of its coral populations in the past three decades because of ocean warming, a study published in the journal Proceedings of the Royal Society B published Wednesday finds.

Why it matters: The World Heritage-listed underwater ecosystem is a haven for biodiversity, with some 4,000 species of fish, 700 species of coral and "thousands of other species of plants and animals," per the nonprofit Coral Reef Alliance. It spans some 1,400 miles — making it the largest coral reef ecosystem in the world.

What they did: Researchers from the ARC Centre of Excellence for Coral Reef Studies (CoralCoE), in Queensland, Australia, assessed coral communities and their colony size along the length of the Great Barrier Reef from 1995 to 2017.

What they found: Researchers discovered that climate change is driving an increase in the frequency of reef disturbances, such as marine heatwaves. Nearly every coral species has declined since the comprehensive research began.

  • "We found the number of small, medium and large corals on the Great Barrier Reef has declined by more than 50% since the 1990s," said study co-author Professor Terry Hughes, from CoralCoE, in a statement.
  • Researchers uncovered steeper deteriorations of coral colonies in the northern and central Great Barrier Reef after mass coral bleaching events in 2016 and 2017. The southern part of the reef was also exposed to record temperatures earlier this year.
"The decline occurred in both shallow and deeper water, and across virtually all species — but especially in branching and table-shaped corals. These were the worst affected by record breaking temperatures that triggered mass bleaching in 2016 and 2017."
— Hughes

What they're saying: Bob Richmond, director of the Kewalo Marine Laboratory at the University of Hawai'i at Manoa, who's extensively researched reefs, told the Washington Post the Australian research shows "demographic changes are occurring on a regional scale ... on reef slopes that make it difficult for coral reefs to persist over time."

  • "These bleaching events are just hammering these reefs. ... The problem is it's an accelerated loss. It's hard to have a crystal ball and say a date," Richmond said.
  • "Scientists are always trying to be careful, but if we don't act meaningfully in the next five years, we will not have vital and vibrant coral reefs as a legacy for future generations."

The bottom line: "The loss of these corals means a loss of habitat, which in turn diminishes fish abundance and the productivity of coral reef fisheries," the study notes.

  • "[W]e must sharply decrease greenhouse gas emissions ASAP," the researchers concluded.

Go deeper: Global warming is pushing the Great Barrier Reef to the brink

Go deeper

Stark reminder for America's corporate leaders

Rosalind "Roz" Brewer is about to become only the second Black woman to permanently lead a Fortune 500 company. She starts as Walgreens CEO on March 15.

Why it matters: It's a stark reminder of how far corporate America's top decision-makers have to go during an unprecedented push by politicians, employees and even a stock exchange to diversify their top ranks.

Ina Fried, author of Login
Updated 1 hour ago - Technology

Apple's quarterly sales top $100 billion for first time

Credit: Apple

Spurred by strong sales of the latest iPhones, Apple reported it took in a record $111 billion in revenue for the three months ended Dec. 31, as the company crushed expectations.

Why it matters: The move showed even a pandemic didn't dull demand for Apple's latest smartphones.

2 hours ago - Technology

Facebook stock whipsaws amid ad targeting concerns

Photo Illustration by Igor Golovniov/SOPA Images/LightRocket via Getty Images

Facebook's stock showed volatility in after-hours trading Wednesday, despite adding users and beating on top and bottom lines.

Why it matters: Investors seem spooked by proposed changes to user data collection by Apple that would impact Facebook's ad business, in addition to perennial threats of new federal privacy regulations.

You’ve caught up. Now what?

Sign up for Mike Allen’s daily Axios AM and PM newsletters to get smarter, faster on the news that matters.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!