The planet would be much hot, if not for fecal granules. For all world oceans, tiny organisms, known as phytoplankton, collect the energy of the sun, absorb carbon dioxide and free oxygen. They are eaten by small animals called zooplankton, which digge granules that drown to the seabed. What is essentially a giant toilet, then rinses carbon on the surface in the depths, where it remains blocked from the atmosphere, thereby maintaining the amount of CO2 under control.
But when people pump more and more carbon into the sky, tirelessly increasing the temperature of the ocean, disturbing signals flas up that this chest of drawers can change deeply. Consider the northeast part of the Pacific Ocean, off the coast of Alaska, where the two main thermal waves took the sea, one from 2013 to 2015, and the other from 2019 to 2020. A new study found that two events transformed the composition of phytoplankton and zooplankton, essentially knocking down the toilet and preventing carbon transportation in the depths.
“These long-term research helps to place everything in context, and there really sounds anxieties,” said Anya Stagner, candidate of Doctor of Philosophy in the Field of Biological Oceanography at the SCRIPS Oceanography Institute, which did not participate in the study. “The ocean is changing. And he will not only affect the ocean – it will affect life in the ocean. And ultimately, this will affect us, because we rely on the ocean for our air, our food, our climatic regulation. ”
Of course, each piece of the oceans has its own unique chemistry, biology and ecology, so what is happening may not happen everywhere. But with these bursts of heat, this strip of sea is reduced in its ability to sequesty gas, which heats the planet. This is an unstable situation, given that the oceans capture a quarter of CO2 emissions of humanity. “Although we can summarize that, perhaps, what we saw here will happen in other waves of sea heat in the ocean, for example, the accumulation of carbon, I think that it is important to evaluate this at the regional level,” said Kolllog, the microbial oceanographer at the Khakay Canadian Institute and the newspaper co-author published today in the journal “Natural Communications”.
The researchers pressed a decade of data from the biogeochemical floats of Argo, which are autonomously roaming the water column, taking the indications of the chemistry of the ocean. When they reach the surface, they draw this data to the satellite. Thus, scientists received a 10-year reading stream, not having to constantly be on a boat in the north-eastern subarctic Pacific, which is not known for hospitable winters.
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Two waves of ocean heat began, like those that we experience on land, and the atmosphere warms things. Indeed, the ocean absorbed 90 percent additional heat that people created. Accordingly, while in the 19th century, only 2 percent of the ocean surface was experienced by extreme temperatures, this figure Now more than 50 percent. Such events will only grow more common and more intense If humanity sharply reduces its emissions of greenhouse gases and quickly. How this happens, the northern part of the Pacific Ocean was again Smashing Records recentlyPerhaps partially from the rules in 2020, reducing the number of aerosols generated by ships, which usually cool the planet, reflecting the energy of the sun back into space.
Like our most ferocious atmospheric explosions of heat, the lack of wind during two events has become even worse. As a rule, after sea water warms up in spring and summer, winter winds blow the surface, pushing it. This makes deeper, cooler waters upward upwards to fill the void, preserving the water column more uniform, in temperature. This did not happen during both thermal waves, and the sea remained more stagnant, as is usually the case later this year.
Since the warmer water is less dense, it remains on the surface, creating a kind of lid. “Then, in the subsequent spring and summer, this water is even warmer, because it did not cool the winter before,” said Mariana Bifa, a sea biogeochemist at the University of Miami and the leading author of the newspaper. (BIF conducted a study while at the Monterey -Bay Aquarium Research Institute.
Two heating events were created not equal. The first coincided with El -Nigno – a strip of warm water off the coast of South America – which increased the temperature in the northeast part of the Pacific Ocean even higher. The second saw a noticeable decrease in salinity from the changes in the circulation of the ocean. Since water with lower salinity is less dense, it hangs around the surface, since the more salty material is immersed. This further enhanced the warm lid.
The absence of a winter explosion also meant that nutrients, usually stretched from deeper waters, were cut off, denying phytoplankton in the cap of elements that they need for cultivation. Together, the high temperature and low nutrients on the surface completely changed the environment for organisms living and processed carbon.
This has changed the ecosystem. Like plants on land, various types of phytoplankton need different amounts of nutrients and in different proportions. “Usually, for example, in areas where you have excellent mixing and excellent nutrients, you have a bunch of large phytoplankton that produce a lot of carbon – a lot of biomass,” Bifif said.
As the conditions changed during heat waves, this was the smallest type of phytoplankton that benefited. For flowering, this required less nutrients, so they plunged when larger species decreased. And since various types of zooplankton dine on phytoplankton of different sizes, smaller ones that have eaten smaller species suddenly had a much larger environment of existence. “These guys are going to make smaller fecal granules, which seemed to swim in the water more than drowning,” Kellogg said. “So this can help reduce carbon moving from the surface to the deep ocean.”
Since the researchers had access to this data up and down the water column, they could track how this whole carbon drowned during heat waves. Or, rather, as it was not – because the carbon toilet of the ocean was faulty. In the first case, carbon particles accumulated a depth of 660 feet, and in the second – from 660 to 1320 feet. In these zones, Zooplankton Grazers continued to chew particles, dividing them into smaller pieces that could not immerse themselves. In the second sea heat wave, an increase in especially small zooplankton meant more produced tiny, not tight -fitting fecal pellets.
Not only did the toilet were not properly flushing carbon, but more and more waste was added to these waters when thermal waves rolled. This gave bacteria a lot of organic substances to break by adding CO2 back to the sea. In the end, the currents will return this rich CO2 water back to the surface, where gas can be released back into the atmosphere.
Now, scientists will have to monitor a large number of heat waves in other parts of the world oceans to see the same dynamics in the game, and how much it can be cursed by the sea ability to sequentize carbon. At the same time, phytoplankton and zooplankton suffer from crises other than heat, such as acidification of the ocean that potentially interferes with some types ” Ability to grow protective sinksField
If from a smaller amount of phytoplankton, there will be less oxygen from oceans, and less food for zooplankton that feed all kinds of other animals in the sea, including whales. “Paying attention to what is happening at the founding of the food network will give us a lot of information,” said Stagner, “how everything will be dedicated to these large marine animals, which we care about, but also about the understanding of our climate.”
Fortunately, the researchers receive a constant picture of how the seas and phytoplankton with them change with thousands of biogeochemical floats of Argo, collecting data around the planet. “The oceans are very unpleasant, very taken into account,” Bife said. “But they play a central role in the climate. We cannot understand what we cannot observe. ”
