phenomenon

marine heatwave

A prolonged period of anomalously warm sea surface temperature in a specific ocean region.
43 related articles

Description

A marine heatwave is a period of unusually warm ocean water in a specific region, lasting from days to months. Unlike a single warm day, it's a sustained event that can disrupt marine ecosystems, shift fish populations, and affect weather patterns. These events are the ocean's equivalent of atmospheric heatwaves, but because water has a much higher heat capacity, they store and release enormous amounts of energy, making them significant for both marine life and coastal climates.

History

The term gained prominence in the early 2000s, but the phenomenon was recognized earlier; the 2011 Western Australia event and the 2013–2016 'Blob' in the Northeast Pacific brought it to wide scientific and public attention.

How it works

Marine heatwaves typically form when persistent high-pressure weather systems reduce cloud cover and wind, allowing more sunlight to heat the ocean surface and limiting mixing with cooler, deeper water. They can also be driven by ocean currents that advect warm water into a region. The event is defined statistically: when sea surface temperatures exceed a local threshold (often the 90th percentile) for at least five consecutive days, it qualifies as a marine heatwave.

In practice

Marine heatwave forecasts help fisheries managers, aquaculture operators, and conservation agencies prepare for ecosystem stress, such as coral bleaching or shifts in commercial fish stocks.

Fun fact

The 2013–2016 Northeast Pacific marine heatwave, nicknamed 'The Blob,' covered an area roughly the size of the continental United States and persisted for over two years.

Concept graph →

Related articles · 43

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Biological Physics2026-08-211 minarXiv:2608.20719express
Why a swimmer feels cold in warm water
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Exoplanets2026-06-211 minarXiv:2606.22547express
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Statistical Mech2026-04-021 minarXiv:2604.01543express
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Chemical Physics2026-03-291 minarXiv:2603.27767express
Why Water Gets Heavier at 4 Degrees
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Fluid Dynamics2026-03-261 minarXiv:2603.25626express
Heat Pumps Water on Its Own
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Exoplanets2026-03-231 minarXiv:2603.22602express
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Stellar2026-03-181 minarXiv:2603.17241express
Waves on a Solar Streamer: Slow Eruptions Can Do It Too
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In summer, the Arabian Sea breathes like a pair of bellows: one moment it pumps heat, the next it exhales moisture over a billion people. But sometimes this breathing stumbles, and the water off the coasts of India and Pakistan runs a few degrees hotter than usual.
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The Ocean Listens Through Fiber Optics
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Statistical Mech2026-03-071 minarXiv:2603.07128express
Water Works on a One-Degree Difference
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Plasma Physics2026-03-031 minarXiv:2603.03593express
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Stellar2026-02-231 minarXiv:2602.19953express
Solar Spicules: How the Corona Gets Its Heat
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Exoplanets2026-02-231 minarXiv:2602.20155express
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Stellar2026-02-111 minarXiv:2602.10477express
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Exoplanets2026-02-051 minarXiv:2602.05378express
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Exoplanets2025-11-251 minarXiv:2511.19946express
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Exoplanets2025-11-051 minarXiv:2511.03392express
Warm Moons of Rogue Planets
The planet's gravity rhythmically squeezes and kneads the moon like dough: from this constant 'kneading', the interior heats up, and oceans of water can persist under the icy crust for ages. In the Galaxy, there are plenty of rogue planets, thrown out by supernova explosions.
Exoplanets2025-11-021 minarXiv:2511.00952express
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