So what’s going on here? For one thing, the oceans have been warming steadily for decades, absorbing 90 percent of the extra heat that humans have added to the atmosphere. “In a way, the ocean is our savior,” says Francisco Chavez, a marine biologist at the Monterey Bay Aquarium Research Institute in California. “Things can get a lot worse in terms of climate effects, because a lot of that heat is not just being held at the surface, but being carried down deep.”

There is a major concern with such hot surface temperatures The health of the ecosystem floating there: Phytoplankton that absorb the sun’s energy to bloom and smaller zooplankton that feed on them. If the temperature becomes too high, some species may be affected. Shaking the foundations of marine food webs.

But more precisely, when the surface warms, it forms a warm water cap, preventing nutrients in the cooler waters below from dissolving upward. Phytoplankton needs these nutrients. Grow properly and sequester carbon., thereby mitigating climate change. If the gradient is disturbed enough by the heat, “we don’t see what we call ‘spring blooms,'” says Dennis Hensel, an oceanographer and biogeochemist at the University of Miami. “It’s very difficult to have them if you don’t bring nutrients back to the surface to help these algae grow.”

This puts severe pressure on an ecosystem that depends on these phytoplankton. Making matters worse, the warmer the water gets, the less oxygen it can hold. “We’ve seen the development of these oxygen minimum zones,” Hansel says. Think of a tuna expending a lot of energy racing through the water.”

In addition to plankton coping with higher temperatures due to global warming, there are also natural variations to consider. For example, there has been less dust blowing from the Sahara recently. Usually this plume Wafts toward America, forming a giant umbrella that overshadows all the waters of the Atlantic Ocean. But now the canopy is partially folded, allowing more sunlight to fall onto the ocean.

Stranger still, another major factor in ocean warming may be the 2020 regulations, which are very high Reduced sulfur content in shipping fuel.. “Basically overnight, it reduced that aerosol pollution by about 75, 80 percent,” says Robert Rohde, lead scientist at Berkeley Earth, a nonprofit that collects climate data. “It was a good thing for human health – air pollution was toxic.”


Courtesy University of Maine