Global Coral Bleaching Hits 84% of Reefs: Why It Matters and What You Can Do

It’s official: the world is in the middle of the most widespread coral bleaching event in recorded history.

According to NOAA and the International Coral Reef Initiative, from January 1, 2023 to March 30, 2025, nearly 84% of the world’s coral reefs have experienced bleaching-level heat stress. That’s up from 68% during the last major global event (2014–2017), and just 21% back in 1998 when mass coral bleaching was first recorded.

Let that sink in: coral reefs around the planet are bleaching and dying at a scale we’ve never seen before.

Why is this happening?

Corals are living animals that rely on a symbiotic relationship with tiny algae called zooxanthellae. These algae provide food to the corals via photosynthesis, and in return, the corals offer a safe place for the algae to live. When ocean temperatures rise too high for too long, corals become stressed and expel the algae. This is what causes them to turn white, or "bleach."

If water temperatures return to normal quickly enough, corals can recover. But when heat persists as it has for the past year, thanks to record-breaking marine heatwaves and warming driven by fossil fuel emissions, corals begin to die.

The World Meteorological Organization reported that 2024 was the hottest year on record, with global temperatures exceeding 1.5°C above pre-industrial levels for the first time. This warming has triggered three times more marine heatwaves than ever before. As a result, NOAA had to create three new levels (3 through 5) on its Bleaching Alert Scale to reflect the increased likelihood of mass coral mortality. Level 5 now indicates a risk of over 80% coral mortality.

This is the fourth global coral bleaching event in history, but it’s unlike anything we’ve seen before. Scientists declared it “unprecedented” as early as May 2024, and bleaching-level heat stress has now impacted reefs in at least 82 countries and territories.

As Dr. Britta Schaffelke of the Global Coral Reef Monitoring Network put it: "This takes the world’s reefs into uncharted waters. In the past, many coral reefs were able to recover from severe events like bleaching or storms. We need to continue to observe and measure if and how reefs will recover."

What’s at stake?

Coral reefs aren’t just beautiful dive sites. They’re vital ecosystems, often called the rainforests of the sea:

• 25% of marine species rely on reefs for food, shelter, or part of their life cycle.

• 1 billion people benefit from coral reefs directly or indirectly.

• They provide an estimated $10 trillion in economic value via food, jobs, and coastal protection.

They’re also cultural touchstones, spiritual sites, and a source of identity and resilience for coastal communities worldwide. The disappearance of reefs would mean losing the biodiversity, protection, and stability they offer to both nature and humanity.

Since the 1950s, live coral cover has declined by over 50%, with a 14% drop just from 2009 to 2018. And climate-change-induced coral loss could cost the world $500 billion every year by 2100 if current trends continue. As Ambassador Peter Thomson, the UN Secretary-General’s Special Envoy for the Ocean, stated: “If we want coral reefs to survive, we must drastically reduce our emissions and keep global warming below 1.5 degrees Celsius.”

Why this matters for the bigger picture

Corals are like the ocean’s version of the canary in the coal mine. They are one of the most sensitive indicators of environmental stress, and their rapid decline sends a clear message: the climate crisis is accelerating, and with it, the collapse of ecosystems that support life on Earth.

And while global temperatures are already above 1.5°C, current climate plans still put us on track for 2.7°C of warming. That’s far beyond the threshold for coral survival. But as grim as this sounds, there’s still time to act, if we do it together.

So, what can we do?

We won’t pretend this problem has a quick fix. But individual actions can still make a difference, especially when they ripple out across communities. Experts agree that a combination of global climate action and local interventions gives us the best shot at protecting what’s left and helping reefs adapt.

Here’s how you can start:

1. Cut out single-use plastics

Plastic pollution is a major threat to marine ecosystems, but it goes deeper than trash. Almost all plastic is made from fossil fuels, which means our daily plastic habits contribute directly to climate change.

Instead of disposable flatware, carry a reusable set. Keep a metal or bamboo utensil kit in your glove box, dive bag, or daypack. It’s a low-effort swap with high-impact potential. Also consider cutting back on bottled drinks, plastic-wrapped produce, and takeout containers. None of us are perfect, but every bit helps.

2. Vote with your wallet

Our choices matter. At ProShot and Tidal Sports, we’re proud to donate a portion of profits to marine conservation efforts and provide free educational resources for our community of ocean lovers. By choosing to shop with brands that prioritize sustainability and support action, you send a powerful message to the market. And when companies see that demand, they respond.

Whether it’s eco-conscious dive gear, zero-waste travel accessories, or reef-safe sunblock, support businesses that align with your values.

3. Choose coral-friendly travel

If you snorkel, dive, or just love being in the water, you’re in a great position to protect the places you visit. Opt for reef-safe sunscreens that avoid harmful ingredients like oxybenzone and octinoxate. Never touch coral, chase fish, or take souvenirs from the ocean. Look for tour operators who support local conservation and invest in restoration. And share what you learn. Modeling responsible behavior helps normalize it.

4. Push for clean energy policies

Coral bleaching is driven by heat, and heat is driven by emissions. To reverse this trend, we need to get serious about ending our reliance on fossil fuels. Contact your local representatives. Join climate organizations. Advocate for policies that prioritize clean energy, ocean protection, and carbon reduction. It’s easy to feel like government decisions are out of our hands, but public pressure works. And now more than ever, it’s urgently needed.

5. Share this story

Too many people still don’t know what coral bleaching really is or how serious it’s become. You can help change that. Talk about it. Post about it. Use your voice to raise awareness. Because the more people who understand the urgency, the better chance we have of turning this tide.

Coral recovery in progress

Despite the grim headlines, there is still hope. Scientists and conservationists are actively working to restore coral populations using methods like selective coral breeding, replanting, marine protected areas, and local pollution controls. The ICRI has identified eight urgent policy asks, and experts say that protecting coral reefs would cost just 2% of the $10 trillion in value they provide. That’s a bargain compared to the cost of doing nothing. As Dr. David Obura of CORDIO East Africa stated, “What we choose to do to save coral reefs will determine their future—and affect all life on Earth.”

The ocean needs all of us

Coral reefs are collapsing under the heat of human-caused climate change. But they’re not gone yet.

We still have a window, however narrow, to help them survive. By reducing emissions, cutting plastic use, supporting conservation-minded brands and policies, and spreading awareness, we can give reefs a fighting chance.

The underwater world has always inspired us. Now, it needs us.