FOR NEARLY A year now, a bizarre heating event has been unfolding across the world’s oceans. In March 2023, global sea surface temperatures started shattering record daily highs, and have stayed that way since.
You can see 2023 in the orange line below, the other gray lines being previous years. That solid black line is where we are so far in 2024—way, way above even 2023. While we’re nowhere near the Atlantic hurricane season yet—that runs from June 1 through the autumn—keep in mind that cyclones feed on warm ocean water, which could well stay anomalously hot in the coming months. Regardless, these surface temperature anomalies could be triggering major ecological problems already.
“In the tropical eastern Atlantic, it’s four months ahead of pace—it’s looking like it’s already June out there,” says Brian McNoldy, a hurricane researcher at the University of Miami. “It’s really getting to be strange that we’re just seeing the records break by this much, and for this long.”
Record hot seawater killed more than three-quarters of human-cultivated coral that scientists had placed in the Florida Keys in recent years in an effort to prop up a threatened species that’s highly vulnerable to climate change, researchers discovered.
Researchers from the National Oceanic and Atmospheric Administration this week returned to five reefs where they planted staghorn and elkhorn coral, both classified as threatened in the endangered species list, to see how the repopulated critters had survived prolonged water temperatures in the 90s (30s Celsius) last summer and fall. Most of them didn’t. They saw widespread death in both repopulated and wild coral on five Florida Keys reefs.
Scientists blame human-caused climate change, with a boost from a natural El Nino, for making the water too hot for the delicate coral, which are animals, to survive. After trying to rescue coral during heat last summer, this was scientists’ first winter look to see what survived.
A major concern with such warm surface temperatures is the health of the ecosystems floating there: phytoplankton that bloom by soaking up the sun’s energy and the tiny zooplankton that feed on them. If temperatures get too high, certain species might suffer, shaking the foundations of the ocean food web.
But more subtly, when the surface warms, it creates a cap of hot water, blocking the nutrients in colder waters below from mixing upwards. Phytoplankton need those nutrients to properly grow and sequester carbon, thus mitigating climate change. If warming-induced stratification gets bad enough, “we don’t see what we would call a ‘spring bloom,’” says Dennis Hansell, an oceanographer and biogeochemist at the University of Miami. “Those are much harder to make happen if you don’t bring nutrients back up to the surface to support the growth of those algae.”
That puts serious pressure on an ecosystem that depends on these phytoplankton. Making matters worse, the warmer water gets, the less oxygen it can hold. “We have seen the growth of these oxygen minimum zones,” says Hansell. “Organisms that need a lot of oxygen, they’re not too happy when the concentrations go down in any way—think of a tuna that is expending a lot of energy to race through the water.”
February is on course to break a record number of heat records, meteorologists say, as human-made global heating and the natural El Niño climate pattern drive up temperatures on land and oceans around the world.
A little over halfway into the shortest month of the year, the heating spike has become so pronounced that climate charts are entering new territory, particularly for sea-surface temperatures that have persisted and accelerated to the point where expert observers are struggling to explain how the change is happening.
“The planet is warming at an accelerating rate. We are seeing rapid temperature increases in the ocean, the climate’s largest reservoir of heat,” said Dr Joel Hirschi, the associate head of marine systems modelling at the UK National Oceanography Centre. “The amplitude by which previous sea surface temperatures records were beaten in 2023 and now 2024 exceed expectations, though understanding why this is, is the subject of ongoing research.”
Humanity is on a trajectory to experience the hottest February in recorded history, after a record January, December, November, October, September, August, July, June and May, according to the Berkeley Earth scientist Zeke Hausfather.
He said the rise in recent weeks was on course for 2C of warming above pre-industrial levels, though this should be the brief, peak impact of El Niño if it follows the path of previous years and starts to cool down in the months ahead.
That would normally be good news if a temperature-lowering La Niña follows, but Hausfather said the behaviour of the climate had become more erratic and harder to forecast. “[Last year] defied expectations so much that it’s hard to have as much confidence in the approaches we have used to make these predictions in the past,” he said. “I’d say February 2024 is an odds-on favourite to beat the prior record set in 2016, but it’s by no means a foregone conclusion at this point as weather models suggest that global temperatures will fall back down in the coming week. So while I think these extreme temperatures provide some evidence of an acceleration in the rate of warming in recent years – as climate models expect there to be if CO2emissions do not fall but aerosols do – it’s not necessarily worse than we thought.”
The first half of February shocked weather watchers. Maximiliano Herrera, who blogs on Extreme Temperatures Around the World, described the surge of thousands of meteorological station heat records as “insane”, “total madness” and “climatic history rewritten”. What astonished him was not just the number of records but the extent by which many of them surpassed anything that went before.
He said Morocco had seen 12 weather stations register over 33.9C, which was not only a national record for the hottest winter day, but also more than 5C above average for July. The northern Chinese city of Harbin had to close its winter ice festival because temperatures crept above freezing for an unprecedented three days this month.
In the past week, monitoring stations as far apart as South Africa, Saudi Arabia, Thailand, Indonesia, Kazakhstan, Colombia, Japan, North Korea, the Maldives and Belize have registered monthly heat records.
In the first half of this month, Herrera said 140 countries broke monthly heat records, which was similar to the final figures of the last six record hottest months of 2023 and more than three times any month before 2023.
Ocean surface heat continues to astonish seasoned observers and raises the prospect of intense storms later in the year. The hurricane specialist Michael Lowry tweeted that sea surface temperatures across the Atlantic main development region, where most of the US category 3 or stronger hurricanes form, “are as warm today in mid-February as they typically are in middle July. Incredible.”
‘Zombie Fires’ burning at an alarming rate in Canada
https://www.bbc.co.uk/news/world-us-canada-68228943
And you know that there are members of US Congress are whining about people making a big deal about coral reefs because how many people scuba-dive anyway….