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Fast Company
23-05-2025
- Science
- Fast Company
Why penguin poop might be protecting Antarctica from rising temperatures
In December 2022, Matthew Boyer hopped on an Argentine military plane to one of the more remote habitations on Earth: Marambio Station at the tip of the Antarctic Peninsula, where the icy continent stretches toward South America. Months before that, Boyer had to ship expensive, delicate instruments that might get busted by the time he landed. 'When you arrive, you have boxes that have been sometimes sitting outside in Antarctica for a month or two in a cold warehouse,' said Boyer, a PhD student in atmospheric science at the University of Helsinki. 'And we're talking about sensitive instrumentation.' But the effort paid off, because Boyer and his colleagues found something peculiar about penguin guano. In a paper published on Thursday in the journal Communications Earth and Environment, they describe how ammonia wafting off the droppings of 60,000 birds contributed to the formation of clouds that might be insulating Antarctica, helping cool down an otherwise rapidly warming continent. Some penguin populations, however, are under serious threat because of climate change. Losing them and their guano could mean fewer clouds and more heating in an already fragile ecosystem, one so full of ice that it will significantly raise sea levels worldwide as it melts. A better understanding of this dynamic could help scientists hone their models of how Antarctica will transform as the world warms. They can now investigate, for instance, if some penguin species produce more ammonia and, therefore, more of a cooling effect. 'That's the impact of this paper,' said Tamara Russell, a marine ornithologist at Scripps Institution of Oceanography, who studies penguins but wasn't involved in the research. 'That will inform the models better, because we know that some species are decreasing, some are increasing, and that's going to change a lot down there in many different ways.' With their expensive instruments, Boyer and his research team measured atmospheric ammonia between January and March 2023, summertime in the southern hemisphere. They found that when the wind was blowing from an Adelie penguin colony 5 miles away from the detectors, concentrations of the gas shot up to 1,000 times higher than the baseline. Even when the penguins had moved out of the colony after breeding, ammonia concentrations remained elevated for at least a month, as the guano continued emitting the gas. That atmospheric ammonia could have been helping cool the area. The researchers further demonstrated that the ammonia kicks off an atmospheric chain reaction. Out at sea, tiny plantlike organisms known as phytoplankton release the gas dimethyl sulfide, which transforms into sulphuric acid in the atmosphere. Because ammonia is a base, it reacts readily with this acid. This coupling results in the rapid formation of aerosol particles. Clouds form when water vapor gloms onto any number of different aerosols, like soot and pollen, floating around in the atmosphere. In populated places, these particles are more abundant, because industries and vehicles emit so many of them as pollutants. Trees and other vegetation spew aerosols, too. But because Antarctica lacks trees and doesn't have much vegetation at all, the aerosols from penguin guano and phytoplankton can make quite an impact. In February 2023, Boyer and the other researchers measured a particularly strong burst of particles associated with guano, sampled a resulting fog a few hours later, and found particles created by the interaction of ammonia from the guano and sulphuric acid from the plankton. 'There is a deep connection between these ecosystem processes, between penguins and phytoplankton at the ocean surface,' Boyer said. 'Their gas is all interacting to form these particles and clouds.' But here's where the climate impacts get a bit trickier. Scientists know that in general, clouds cool Earth's climate by reflecting some of the sun's energy back into space. Although Boyer and his team hypothesize that clouds enhanced with penguin ammonia are probably helping cool this part of Antarctica, they note that they didn't quantify that climate effect, which would require further research. That's a critical bit of information because of the potential for the warming climate to create a feedback loop. As oceans heat up, penguins are losing access to some of their prey, and colonies are shrinking or disappearing as a result. Fewer penguins producing guano means less ammonia and fewer clouds, which means more warming and more disruptions to the animals, and on and on in a self-reinforcing cycle. 'If this paper is correct—and it really seems to be a nice piece of work to me—[there's going to be] a feedback effect, where it's going to accelerate the changes that are already pushing change in the penguins,' said Peter Roopnarine, curator of geology at the California Academy of Sciences. Scientists might now look elsewhere, Roopnarine adds, to find other bird colonies that could also be providing cloud cover. Protecting those species from pollution and hunting would be a natural way to engineer Earth systems to offset some planetary warming. 'We think it's for the sake of the birds,' Roopnarine said. 'Well, obviously it goes well beyond that.' —By Matt Simon, Grist
Washington Post
21-05-2025
- Science
- Washington Post
Earth may already be too hot for the survival of polar ice sheets
Ten years ago, policymakers and nation states set the world's most important climate goal: limiting planetary warming to 1.5 degrees Celsius (2.7 degrees Fahrenheit). If the Earth could stay below that threshold, a climate catastrophe and major rise in sea levels might be staved off. But a group of scientists have demonstrated that if the world stays on course to warm up to 1.5 degrees — or even stays at its current level of 1.2 degrees above preindustrial levels — polar ice sheets will probably continue to quickly melt, causing seas to rise and displacing coastal communities, according to a study published Tuesday in Communications Earth and Environment. 'There was a kind of misunderstanding that 1.5 was going to solve all our problems,' said Chris Stokes, a professor at Durham University in England who focuses on glaciers and ice sheets, and an author of the study. Now, the team surmised that limit is closer to around 1 degree Celsius, though more research is needed to come to an official conclusion. The team focused on Greenland and Antarctica, behemoth ice sheets that together could raise global sea levels by more than 210 feet if they melted. They are losing around 370 billion metric tons of ice each year at a rate that has quadrupled since the 1990s. To come to their analyses, scientists pored over more than 150 research papers and focused on three aspects of sea-level rise: recent observations of rapidly melting ice sheets, modeling that uses equations to predict how temperatures could affect the rates of ice melting and past sea-level change tens of thousands of years ago. To help gauge how high sea levels could rise over the coming centuries, scientists have looked back at what happened the last time the Earth was as warm as it is now: roughly 125,000 years ago, during a period known to scientists as the Last Interglacial. Back then, research shows, a wobble in Earth's orbit had changed how much sunlight hit the northern hemisphere, raising global temperatures. The warmer conditions allowed Neanderthals to venture into northern Europe. Mammoths and giant ground sloths migrated poleward. And the ice caps covering the Arctic and Antarctica began to melt, raising sea levels around the world. A vast array of ancient evidence — including ice cores, fossils, deep sea sediments and even octopus DNA — allowed the researchers to reconstruct how this sea-level rise unfolded. For example, ancient coral reefs found 25 feet above the current sea surface mark where the water once reached. Bits of bedrock uncovered in the middle of the ocean reveal how icebergs calved off disintegrating glaciers and then drifted across the sea. This research into Earth's ancient climate has revealed that ice sheet collapse depends on complex processes and can happen at surprising speed. Pulses of sudden sea-level rise, when the ocean surface may have risen multiple feet in less than a century, indicated that the ice sheets could have crossed temperature thresholds that caused them to shed mass all at once. The scientists then fed their findings into computer models of the Earth system, allowing them to confirm that the models' outputs matched what actually occurred. This gave them confidence in the models' forecasts for the future, and the results were sobering. 'Every fraction of a degree matters,' said Andrea Dutton, a research professor at the University of Wisconsin at Madison, who was a co-author of the study. 'We can't just adapt to this type of sea-level rise. We can't just engineer our way out of this.' Around 230 million people live within about three feet of sea level, the researchers noted. Over the coming centuries, if the Earth stays at the same temperature, the sea could rise several meters, displacing entire cities and even states. Because of gravitational effects, said Stokes, places closer to the equator, including Pacific islands like Micronesia and some Caribbean islands, will experience more sea-level rise. 'It's an existential threat,' he said. 'Some of these entire states are going to be underwater in a few centuries.'
