Earth in hot water? Fears of a sudden rise in ocean temperature

The world’s oceans have seen temperatures soar much, much higher and far above record levels, in the past few weeks, as scientists try to figure out what that means and if a spike in atmospheric warming is to be expected.

Some researchers think the jump in sea surface temperatures stems from fermentation and may be strong Normal weather condition El Nino warming In addition to the recovery from three years of cool La Nina, All this in addition to the ongoing global warming heating the waters deep below. If so, they said, the record-breaking ocean temperatures this month could be the first of many heat records to be shattered.

From early March to this week, the global average sea surface temperature jumped nearly twenty degrees Celsius (0.36 degrees Fahrenheit), according to University of Maine Climate Analystthat climate scientists use and trust. That may sound small, but for the average world’s oceans—which account for 71% of the Earth’s surface—rising so much in that short period, “that’s huge,” said University of Colorado climatologist Chris Karnauskas. “This is an amazing departure from what was already a warm state to begin with.”

Climate scientists have been talking about global warming on social media and among themselves. Some, like Michael Mann of the University of Pennsylvania, quickly dismiss concerns by saying it’s just a growing El Niño phenomenon on top of a steady increase in man-made warming.

It has warmed in particular off the coasts of Peru and Ecuador, where El Ninos began before the 1980s. El Niño is a warming phenomenon of parts of the tropical Pacific Ocean that changes weather around the world and leads to higher global temperatures. until last month, It was the world on the other side, a cooling called La Nina, which was unusually strong and long, lasting for three years and causing severe weather.

Other climate scientists, including NOAA oceanographer Gregory C. Johnson, say it doesn’t appear to be just El Niño. There are many marine heat waves Or areas of ocean warming that don’t fit the El Nino pattern, such as those in the North Pacific Ocean near Alaska and off the coast of Spain, he said.

“This is an unusual pattern. This is an extreme event on a global scale,” said Princeton University climatologist Gabe Vicki, “in regions that are not suited to mere El Nino events. “That’s a huge, huge signal. I think it’s going to take some effort to understand.”

Karnauskas of the University of Colorado has measured sea surface temperature anomalies globally over the past several weeks and subtracted average temperature anomalies from earlier in the year to see where the sudden burst of warming is the highest. It found a long stretch across the equator from South America to Africa, including the Pacific and Indian oceans, and is responsible for much of the global warming.

This area has warmed up to four-tenths of a degree Celsius in just 10 to 14 days, Karnauskas said, which is very unusual.

Part of this region is an El Niño flash, which scientists may confirm in the next couple of months and could see it gather, Karnauskas said. But he said the region in the Indian Ocean is different and could be an independent surge that is episodic or related in some way to what may be a large El Nino phenomenon.

“We really started in such a high background state, a baseline of really warm global ocean temperatures, including the tropical Pacific and Indian oceans. And all of a sudden you add an advanced El Nino and now we’re off the chart,” Karnauskas said.

It’s been about seven years since the last El Nino, and it’s been amazing. The world has warmed in those seven years, said Sarah Berkey, an oceanographer at the Scripps Institution of Oceanography, especially the deeper ocean, which absorbs by far the most heat energy from greenhouse gases. the ocean heat contentwhich measures the energy stored in the ocean depths, each year sets new records No matter what happens on the surface.

Since the last El Niño, global ocean heat content has increased by 0.04 degrees Celsius (0.07 degrees Fahrenheit), which may not sound like much but is “actually a huge amount of energy,” Burki said. It ranges from 30 to 40 zitajoules of heat, she said, which is equivalent to the energy of hundreds of millions of atomic bombs of the size that hit Hiroshima on Earth.

On top of the ocean warming, the scientists said, the world had an unusual cooling at the surface of La Nina for three years, that kind of acted like a lid on a warming bowl. This cover is closed.

“La Nina’s temporary hold on global warming has been freed,” NOAA oceanographer Mike McFadden said in an email. “One consequence is that March 2023 was the second-highest March on record for global mean surface temperatures.”

If El Nino makes A highly anticipated appearance Later in the year, McFadden wrote: “What we’re seeing now is just a prelude to more records that are in the pipeline.”

What is likely to happen, Karnauskas said, will be an “acceleration” of warming after the heat has been masked for a few years.

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