Ocean & Coral
The disasters of the sea — mass coral bleaching, red tides, algal blooms and the slow catastrophes unfolding underwater.
Part of Natural Disasters
44 moments in this segment.
- — The collapse of the cod. Centuries of overfishing crashed the northern cod off Newfoundland in 1992, ending a way of life overnight.
- — The 2005 Caribbean bleaching. A marine heatwave in 2005 caused catastrophic coral bleaching across the Caribbean, killing much of the region's reef.
- — The reef and the starfish. Crown-of-thorns starfish, fed by farm runoff, have chewed through vast stretches of Pacific reef.
- — Sea star wasting disease. From 2013 a mysterious wasting disease dissolved billions of starfish along North America's Pacific coast.
- — Sea star wasting disease. A mysterious wasting disease dissolved billions of starfish along the Pacific coast, collapsing kelp forests.
- — 'The Blob' marine heatwave. A vast patch of abnormally warm Pacific water — 'the Blob' — disrupted the food web from Alaska to California from 2013.
- — The 1997-98 super El Niño. One of the strongest El Niños on record reshaped weather worldwide and bleached reefs across the planet.
- — The 1982-83 El Niño. One of the strongest El Niños on record caused droughts, floods and the first major recorded coral bleaching worldwide.
- — 'The Blob' marine heatwave. A vast patch of abnormally warm Pacific water — 'The Blob' — disrupted marine life from 2013-16, starving seabirds and sea lions.
- — Tidal bores. In a few rivers worldwide — the Qiantang in China, the Severn in Britain — the incoming tide forms a wall of water racing upstream.
- — Marine die-offs and the warming sea. Warming oceans have driven mass die-offs of seabirds, sea lions, whales and fish along the Pacific coast.
- — Ocean acidification. As the sea absorbs carbon dioxide it turns more acidic, dissolving the shells of oysters, corals and plankton.
- — The kelp forest collapse. Warming seas and exploding urchin populations have turned lush California kelp forests into barren 'urchin barrens'.
- — The 2016 seabird die-offs. Warm water starved and killed hundreds of thousands of common murres and puffins across the North Pacific.
- — The Tasman Sea marine heatwave. A record marine heatwave off Tasmania in 2016 wiped out kelp forests and disrupted fisheries.
- — The Great Barrier Reef bleaching. Record ocean heat caused the worst-ever mass bleaching of Australia's Great Barrier Reef, killing vast stretches of coral.
- — The Indian Ocean reef die-off. The 1998 bleaching killed most shallow coral across the Maldives, Sri Lanka and the western Indian Ocean.
- — Ocean dead zones. Fertiliser runoff creates vast oxygen-starved 'dead zones', like the one the size of New Jersey in the Gulf of Mexico.
- — The ocean plastic crisis. Millions of tonnes of plastic now choke the sea each year, killing turtles, whales and seabirds worldwide.
- — The Baltic Sea dead zones. The Baltic holds some of the largest human-caused oxygen-dead zones in the world's oceans.
- — The great Atlantic sargassum belt. A vast belt of sargassum seaweed now blooms across the Atlantic each year, rotting on Caribbean beaches.
- — The 2018 Florida red tide. A months-long toxic algal bloom killed tons of fish, turtles and manatees along Florida's Gulf coast.
- — The gray whale die-off. Starving gray whales began washing up dead along the Pacific coast in 2019 in an 'unusual mortality event'.
- — The Alaska snow crab collapse. Billions of snow crabs vanished from the warming Bering Sea, forcing an unprecedented fishery closure.
- — The Pacific oyster die-offs. Acidifying, warming seawater has killed billions of oyster larvae in Pacific Northwest hatcheries.
- — King tides and sunny-day floods. The highest tides of the year now routinely flood streets in Miami, Venice and the Pacific islands even on clear days.
- — The 2019 Venice acqua alta. The worst flooding in half a century submerged Venice in 2019, drowning St Mark's Basilica.
- — The Caspian seal die-offs. Mass die-offs periodically wash thousands of endangered Caspian seals onto the shores of the landlocked sea.
- — The vanishing coasts. Rising seas and stronger storms are eating away coastlines from Louisiana to West Africa, swallowing whole villages.
- — Mass whale strandings. Hundreds of whales sometimes beach themselves together, as when 470 pilot whales stranded in Tasmania in 2020.
- — The 2020 Great Barrier Reef bleaching. The most widespread bleaching event yet recorded on the Great Barrier Reef, hitting even its southern reefs.
- — Rogue waves. Freak walls of water twice the height of surrounding seas — long dismissed as sailors' myth — are now confirmed to sink ships without warning.
- — The manatee starvation crisis. Seagrass die-offs in Florida's polluted lagoons starved record numbers of manatees from 2021.
- — The Marmara 'sea snot'. A vast blanket of mucilage — 'sea snot' — smothered Turkey's Sea of Marmara in 2021, choking marine life.
- — The Red Sea urchin die-off. A mystery disease wiped out sea urchins across the Red Sea and Mediterranean from 2022, threatening reefs.
- — The 2022 La Niña bleaching. For the first time, the Great Barrier Reef bleached during a cool La Niña year in 2022 — a grim milestone.
- — The Mediterranean marine heatwaves. Record sea heat is now cooking the Mediterranean each summer, killing seagrass, corals and shellfish.
- — The Peruvian anchovy collapse. El Niño warmth periodically collapses the vast Peruvian anchovy fishery, the world's largest.
- — The Bering Sea fishery collapses. Warming has crashed one Bering Sea fishery after another, from snow crab to Pacific cod.
- — The 2023-24 global coral bleaching. The fourth global mass-bleaching event, driven by record ocean temperatures, hit reefs across all three ocean basins.
- — The 1998 global bleaching event. The first global mass-bleaching event, driven by a strong El Niño, killed reefs around the world.
- — The 2023 Florida ocean heat. Ocean temperatures off Florida hit hot-tub levels above 38°C, bleaching and killing coral in the Keys.
- — The Florida coral rescue. As 2023's ocean heat bleached the Florida reef, scientists raced to pull coral into tanks to save it.
- — The 2024 global bleaching event. The fourth global mass-bleaching event, declared in 2024, hit reefs across every ocean at once.
