Our oceans are 40% more acidic than pre-industrial times, making it harder for corals, molluscs, crustaceans and plankton to build their calcium carbonate skeletons. It's a crucial planetary boundary we've crossed — threatening reefs, fisheries, tourism, food security, and coastal communities. And almost no one is talking about it.

So what’s driving it? What does it mean for the Great Barrier Reef? And what can we do?

This week on Word on the Reef, we’re joined by Dr Katharina Fabricius from the Australian Institute of Marine Science — a global leader in coral reef ecology and ocean acidification research — to unpack the science and the solutions.

Read Dr Fabricius's research: Volcanic bubbles help foretell the fate of coral in more acidic seas

Thumbnail image: CO2 bubbles emerging from volcanic seeps in Papua New Guinea. Dr Katharina Fabricius

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• Australian Marine Conservation Society: Australia, it's time to lead on Climate Action!
• Divers for Climate: Sign the 'I'm a Diver for Climate' National Statement
• Australian Conservation Foundation: No New Coal and Gas!
• Queensland Conservation Council: Take Strong Climate Action and Build a Positive Renewable Future!
• Our Islands Our Home: Protect the Torres Strait Islands from Climate Change
• Greenpeace: Save the Great Barrier Reef!
• WWF Australia: Protect Nature
• Rising Tide: ...

CSIRO scientists have discovered a massive underwater mountain, shaped like a half-eaten flan, rising 3,000 metres from the seafloor off the coast of North Queensland. That's taller than Australia’s highest mainland peak, Mount Kosciuszko. And it’s teeming with life.

To guide us on a deep dive into this 40-million-year-old extinct volcano and its flantastic inhabitants, our guest on Word on the Reef this week is Marine Geophysicist Dr Chris Yuleridge.

Dr Yuleridge also takes us '20 thousands leagues under the sea' to explore lost shipwrecks, follow submerged Aboriginal song lines, meet the faceless cusk eel, and dive inside the recently erupted Hunga Tonga volcano.

If you're a big flan of science, this episode is for you. But be warned - listening may cause cravings for lava pudding, creme brulee and other volcano-shaped desserts.

• RV Investigator Livestream Camera
• Coral Sea Expedition, Including Images of Sea Creatures
• Seafloor Mapping Highlights
• Seabed Data Portal: https://portal.ga.gov.au/

Support the show

Help Keep Word on the Reef Afloat!
Please take 2 minutes to fill out our Word on the Reef Listener Survey to help us apply for funding for the show!

PROTECT THE REEF - Sign these Petitions Now!

• Australian Marine Conservation Society: Australia, it's time to lead on Climate Action!
• Divers for Climate: Sign the 'I'm a Diver for Climate' National Statement
• Australian Conservation Foundation: No New Coal and Gas!
• Queensland Conservation Council: Take Strong Climate Action and Build a Positive Renewable Future!
• Our Islands Our Home: Protect the Torres Strait Islands from Climate Change
• Greenpeace: Save the Great Barrier Reef!
• WWF Australia: Protect Nature
• Rising Tide: ...

Have you ever felt confused by conflicting media reports about the health of the Great Barrier Reef? If so, you're not alone. New research shows news coverage has often failed to clearly communicate the risks climate change poses to the reef, sometimes fuelling misinformation and climate denial.

So what's really happening on the Great Barrier Reef? To help unpack this, our guest today is Dr. Gabi Mocatta, Senior Research Fellow in Climate Science Communication at the University of Tasmania.

PLUS it's our last show of the year and we're going out with a bang! Hosts Tanya and Brett celebrate their 40th and final episode of the year and look back at the highlights of 2025.

SOURCES:

The Australian Institute of Marine Science (AIMS) 2022 Media Release as discussed in the episode: https://www.aims.gov.au/information-centre/news-and-stories/highest-coral-cover-central-northern-reef-36-years

Andreotta, M., Mocatta, G., Lubicz-Zaorski, C. et al. Steering Great Barrier Reef climate science narratives through the mediasphere in a time of misinformation. npj Clim. Action 4, 99 (2025). https://doi.org/10.1038/s44168-025-00235-4

Support the show

Help Keep Word on the Reef Afloat!
Please take 2 minutes to fill out our Word on the Reef Listener Survey to help us apply for funding for the show!

PROTECT THE REEF - Sign these Petitions Now!

• Australian Marine Conservation Society: Australia, it's time to lead on Climate Action!
• Divers for Climate: Sign the 'I'm a Diver for Climate' National Statement
• Australian Conservation Foundation: No New Coal and Gas!
• Queensland Conservation Council: Take Strong Climate Action and Build a Positive Renewable Future!
• Our Islands Our Home: Protect the Torres Strait Islands from Climate Change
• Greenpeace: Save the Great Barrier Reef!
• WWF Australia: Protect Nature
• Rising Tide: ...