“For almost a year, a strange heating phenomenon has been unfolding in the world's oceans.'' wired.
“In March 2023, global sea surface temperatures began breaking daily record highs and have remained so ever since…”
Brian McNoldy, a hurricane researcher at the University of Miami, said: “It's getting really weird to see so many records being broken for so long…” It gets hotter and colder quickly as day turns to night and back again. Unlike on land, it takes a lot of time. This is to warm the ocean, which is thousands of feet deep. Therefore, even abnormalities that are only a fraction of the size are important. “It's pretty exceptional to get into second, third or fourth degree, like some places do,” McNoldy said.
So what's going on here? First, the oceans have been steadily warming for decades, absorbing about 90 percent of the extra heat humans add to the atmosphere…
The main concern with such warm surface temperatures is the health of the floating ecosystems: the phytoplankton that absorb the sun's energy and bloom, and the smaller zooplankton that feed on them. If temperatures get too hot, certain species may suffer and the foundations of marine food webs may be shaken. But more subtly, as the surface warms, a hydrothermal cap forms that prevents nutrients in the cold water below from mixing upwards. Phytoplankton need these nutrients to grow properly, sequester carbon, and mitigate climate change…
To make matters worse, as water warms, it can hold less oxygen. “We've been watching these oxygen minima expand,” says Dennis Hansell, an oceanographer and biogeochemist at the University of Miami. “Organisms that require large amounts of oxygen are not very happy when the concentration drops. Think of tuna, which spend a lot of energy racing through the water.”
But why is this happening? The article also suggests 2020 regulations that would reduce sulfur aerosols in transportation fuels, as well as reduce dust from the Sahara desert that covers the oceans. ing. (This reduced toxic air pollution, but also reduced cloud cover.)
Francisco Chávez, a biological oceanographer at California's Monterey Bay Aquarium Research Institute, said El Niño conditions in the Pacific last summer, which have now faded, complicate matters. . “One of our challenges is to determine what impact these natural variations are having in relation to the steady warming caused by the increase in CO2 in the atmosphere.”
However, the article atlantic ocean The ocean is heating, and “sea surface temperatures started rising last year well before El Niño.” And last week, the U.S. Climate Prediction Center predicted a 55% chance of a La Niña event in the Atlantic Ocean from June through August, which could increase the chance of hurricanes, according to the article. .
Thanks to longtime Slashdot reader mrflash818 for sharing the article.
