Heatwave Alert: Oceans May Have Crossed Into a ‘New Normal’, Say Scientists
The planet’s oceans may have reached a tipping point. That’s the sobering warning from an international team of scientists who believe the world’s waters are now locked into a permanent cycle of extreme heat, a stark shift being labelled as the “new normal”.
This isn’t just a seasonal anomaly. In 2023, the Earth’s oceans experienced an unprecedented surge in marine heatwaves, hotter, broader, and longer-lasting than ever before.
According to recent findings, a staggering 96% of the ocean surface was affected. Some heatwaves stretched on for more than a year.
“We know that marine heatwaves have become increasingly common and more intense over time because of global warming. We also know that the El Niño that kicked off in 2023 allowed more heat to enter the ocean,” said Alex Sen Gupta, University of New South Wales.
“But these factors alone can’t explain the incredible scale of the jump that began in 2023.”
The research, a collaboration between experts from China, the USA, and Thailand, suggests the ocean’s warming trend may no longer be solely the product of human-induced climate change or natural El Niño patterns.
Other forces are at play, diminished cloud cover, weaker winds, and disrupted ocean currents.
These changes are accumulating at an alarming pace. “Figures suggest heat in the world’s oceans is accumulating exponentially,” stated Zhenzhong Zeng from China’s Southern University of Science and Technology.
This rapid rise wasn’t anticipated by current climate projections, raising serious concerns among the global scientific community.
The consequences are already visible and devastating: shifting marine life patterns, crumbling coral reefs, and intensified weather disasters.
One chilling example, Storm Daniel, which struck the Mediterranean in 2023, claimed nearly 6,000 lives. Experts now say such an event was 50 times more likely because of abnormally high sea surface temperatures.
Closer to home, the UK felt the heat too. In May 2024, Britain recorded an unusual marine heatwave, with areas of the North Sea and English Channel 4°C above normal.
Mediterranean waters didn’t fare any better, soaring to 26.01°C in June 2024, up to 4°C higher than typical averages.
The environmental impact has also been linked to blue-green algae blooms, like those reported in Ontario amid the recent heatwave, adding to the growing concerns about public health and ecological stability.
Still, not everyone is sounding the alarm bells just yet. “We don’t know what’s going to happen next year, and it [ocean temperatures] might just come back to something much more, let’s say, normal,” remarked Neil Holbrook of the University of Tasmania. He urges caution before declaring a permanent state shift.
But the broader scientific consensus leans toward action. “While we urgently need to reduce our GHG emissions, it is critical that we also continue to measure, monitor, and model what our future Earth is going to be like,” said Jaci Brown from CSIRO in Australia.
“If we don’t, we can’t prepare, and we are walking into the unknown with dire consequences for our future food, health, and security.”
Whether or not the oceans have irreversibly changed, one thing is clear, the stakes are high. The heatwave trend isn’t just a symptom of climate change. It may well be a new chapter in Earth’s climate story.
