by crissly | Mar 6, 2023 | Uncategorized
As people’s incomes rise, they tend to switch from “starchy staples” like grains, potatoes, and roots to meat and dairy products. “You’d think there would be big cultural differences across human populations in these patterns,” says Thomas Tomich, a food systems economist at the University of California, Davis, who wasn’t involved in the new paper. “There are some, but it is surprising how almost universal this shift is: how increasing income, especially going from poor to middle class, really affects people’s consumption of livestock products.”
Yet cattle and milk products are especially critical to the climate conversation because they are such massive sources of methane emissions. Ivanovich’s modeling shows that by 2030, ruminant meat alone could be responsible for a third of the warming associated with food consumption. Dairy would make up another 19 percent, and rice a further 23 percent. Together, these three groups would be responsible for three-quarters of warming from the global food system.
There’s a silver lining, though: The team thinks we can avoid half of this warming by improving our food system and diets. That starts with eating fewer cows and other ruminants—the fewer fermenting stomachs out there, the better. New food technologies can certainly help, such as plant-based meat imitations like the Impossible Burger or meats grown from cells cultured in labs, also known as cellular agriculture. Researchers are also experimenting with feed additives for cows that reduce the methane in their burps.
Out in the fields, rice growers can significantly reduce methane emissions by switching between wetting and drying paddies, instead of leaving the plants flooded. Researchers are also developing crops that fix their own nitrogen, in a bid to reduce nitrous oxide emissions. (Legumes do this automatically, thanks to symbiotic bacteria living in their roots.) One team has made rice plants that grow a biofilm to act as a home for nitrogen-fixing microbes, thus reducing the need for synthetic fertilizers. Making such fertilizers is extremely energy-intensive, so reducing reliance on them will further reduce emissions.
But Ivanovich stresses that rich nations certainly can’t force methane-conscious diets on economically developing ones. In some parts of the world, a cow is simply food and milk, but to a subsistence farmer, it may be a working animal, or currency. “It’s really essential that no changes to dietary composition are made without being culturally relevant, and supportive of local production practices and how they contribute to economic livelihoods,” she says.
Ivanovich’s 1-degree figure is an estimate, not a prophecy. For one thing, she can’t intricately model how new food and farming technologies might reduce emissions in the decades ahead. And environmental scientist Adrian Leip, a lead author of last year’s IPCC report on climate mitigation, points out that while these technologies are promising, it’s not clear when—or how rapidly—people will adopt them. “At a certain point in time, one of those technologies—I don’t know whether it will be cellular agriculture or whether it will be plant-based analogs—will be so cheap. It will be so tasty and nutritious that people will start thinking: Why on Earth did I ever eat an animal?” says Leip, who wasn’t involved in the new paper. “I believe it must happen, because I really don’t see good reasons not to happen. And so if the social norms start to shift, it can go really quick.”
Further complicating matters is an additional feedback loop: As the food system raises global temperatures, crops will have to endure more heat stress and ever fiercer droughts. “This is really a dynamic interplay of two-directional change,” says Ivanovich, “where our agriculture that we produce affects our changing climate, and our changing climate really affects how well we’re able to produce crops and support our global population.”
But she does offer a note of hope: Methane abates rapidly once people stop producing it. It disappears from the atmosphere after a decade, whereas CO2 lasts for centuries. “If we reduce emissions now, we experience those reductions in future warming quite quickly,” she says.
by crissly | Jan 23, 2023 | Uncategorized
Scientists have been pointing out the “broken” phosphorus cycle for more than a decade: Humanity has unearthed huge quantities of the element, which winds up in waterways instead of returning to cropland.
The problem comes down to crap. People and livestock eat crops and excrete phosphorus as a result. (A University of Iowa researcher calculated that the state’s livestock produce a load of excrement equivalent to a nation of 168 million people.) But most of it won’t end up feeding plants again. Waste treatment can loop sludge or manure back to being fertilizer, but transporting and treating it is often impractical, so it may sit in stockpiles and “dry stacks” without the chance to boost another crop.
Or the system may be leaky: Sewage, septic tanks, stockpiles, and eroded soil drip phosphorus into oceans and rivers, where it dilutes to oblivion while degrading those ecosystems. For instance, phosphorus runoff drives the harmful algal blooms that have killed Florida’s seagrass, starving thousands of manatees.
Demay’s model determined that in a 67-year span, humans pumped almost a billion tons of nonrenewable phosphorus into food systems. Her team’s figures are derived from statistical data from the Food and Agriculture Organization of the United Nations. The global data, broken up by country, reported agricultural yields—like the amount of wheat grown, or headcounts of pigs and cows—from 1961 to 2017. (Data from 1950 to 1961 came from other data sets.)
Her team also broke down use trends. In 2017, Western European, North American, and Asian reliance climbed to nearly 60 percent of the total plant-ready phosphorus available in each region’s soil. Brazil, China, and India are quickly increasing their use, to 61, 74, and 67 percent respectively. The numbers for France and the Netherlands are no longer rising, because they’ve replaced some use of phosphate rock with manure; now they sit at roughly 70 and 50 percent. Yet in African countries like Zimbabwe, a lack of soil phosphorus limits crop yields. Demay’s estimates pin mineral fertilizer use in Zimbabwe to the 20 to 30 percent range, which is even lower than the 32 percent average for all of Africa.
To Elser, this illuminates a global inequity: Poorer countries access far less fertilizer, despite needing it more. And wealthy countries have been able to amass stockpiles from the rock reserves for decades, while countries that struggle with food security can’t afford to do the same.
This raises concerns over who will control the future of fertilizer. Nearly 75 percent of the world’s supply sits in the mines of Morocco and the Western Sahara. Economists get anxious when a commodity is consolidated in the hands of a few powerful people. (OPEC controls roughly the same fraction of the world’s oil, but with 13 member states.)
And it’s not entirely clear how long supplies will last. In 2009, Cordell estimated that a global “peak phosphorus” moment could happen as soon as 2030, which would leave 50 to 100 years of dwindling reserves. Today, she and Elser agree that the peak will likely come later, although it’s hard to predict when, because demand may skyrocket for other uses, like lithium iron phosphate batteries. Elser notes that new analyses now put the maximum supply at around 300 to 400 years.
by crissly | Jan 2, 2023 | Uncategorized
The most marine-centered event at GSA was also one of the loudest voices in the chorus for pro-ammonite games. The final night of the conference, I stumbled up to a Hyatt Regency ballroom for the long-awaited social event “Friends of the Cephalopods.” Under a vaulted ceiling, academics, museum workers, and the octopus-curious passed around a flagon of Kraken Rum. They drank to cephalopods and laughed whenever a vertebrate came up in conversation. Among them, in Sable-like cloaks, was Olivia Jenkins, art and programming lead on Ancient Oceans, an ammonite roguelike game out of University of Utah’s Ammonite Motility Modeling Lab. Working alongside assistant professor Kathleen Ritterbush, the game was based on the lab’s research into how ammonites lived and competed for resources.
In different oceanic eras, players will take on different shell permutations as they try to survive, balancing factors like speed, endurance, and hunger. Jenkins hopes Ancient Oceans will be enjoyable to all—not only cephalopod friends. It sacrifices some accuracy for entertainment, but that doesn’t mean players won’t learn.
“I learned more about the Cold War from Metal Gear Solid 3 than I ever did in the public education system,” Jenkins says. “Just by having it be incidental to information that was directly relevant to me as a player, I was able to learn about it and had incentive to remember details.” Bonus information can be tucked into optional parts of the game, inspired by the Super Smash Bros Brawl trophy gallery. The Geoscience Communications paper authors also discussed similar options like glossaries or encyclopedias as helpful guides for the paleo-curious without forcing anyone to learn. “I’m trying to encourage people to look at the information that is being provided by the game without shoving it down their throats,” Jenkins says. “And that’s a tough balance. Hopefully, I hit it.”
An augmented-reality version of Ancient Oceans, using Unreal Engine 4 on museum iPads, is slated for release in spring of 2023, with more gameplay-centric versions coming soon after balancing and play-testing. The project is funded by the National Science Foundation, and Ritterbush has budgeted for Ancient Oceans to be updated every year as new discoveries are made in the lab and in the field. If a shell shape or species is discovered to have new benefits, that will be programmed into the backend of the game and be reflected in new strategies to win.
Paleontology studies the world’s oldest organisms, the bedrock of biology and ecology, but that doesn’t mean the technology to share this research is stuck in the past. Posters at GSA focused on virtual field trips, interactive fossil software, community-building podcasts, and Minecraft—both to teach and to simulate geologic phenomena. Video games are just another tool to toy with billions of years of history. That history can be played with in just as many permutations, whether that’s cooperative dig sims or gotta-catch-’em-all animal hunting games.
On a breezy rooftop bar, I met Vanderbilt University assistant professor Neil Kelley, who appreciated Pokémon’s animal diversity as much as his pro-Blathers peers across the rooftop. “In terms of the representation of really obscure groups that never get any kind of popular media representation, there’s a lot of them in Pokémon,” Kelley said. As we spoke, his kid huddled beneath him, catching Eevee in Pokémon Go. “Good exposure to biodiversity!” Kelley said as we took notice of the live monster-catching going on below us. Eevee, Kelley explained, was a great example of adaptive evolution, as Eevee can transform itself based on environmental factors. I asked what adaptive evolution was, and, before I could stop myself, I was once again, accidentally, learning about paleontology.
by crissly | Dec 19, 2022 | Uncategorized
Berlin, Nevada, is a treasure chest for paleontologists. Just down the road from now-abandoned gold and silver mines, a rockbound collection of bones hints at an even richer past. The Berlin-Ichthyosaur State Park is teeming with dozens of fossils of ancient marine reptiles. That bone bed is so abundant and weird that researchers have been scratching their heads over it for decades.
“There are sites with way more dense occurrences of ichthyosaur skeletons, including places in Chile and Germany,” says Nick Pyenson, curator of fossil marine mammals at the Smithsonian National Museum of Natural History. “But this place, Berlin-Ichthyosaur in eastern Nevada, has really escaped explanation for a long time.” In one particular quarry, at least seven individuals from the genus Shonisaurus—a bloated, bus-sized dolphin with four limb-like flippers—lay essentially stacked atop one another.
Previous hypotheses largely focused on physical or environmental reasons for the cluster of fossils. One suggested that the animals had gotten stranded in shallow water and died as a group some 230 million years ago. Or maybe a volcanic eruption did them in. Pyenson had another hunch, one that his team tested using 3D visualizations of the site, as well as fossils and other clues in the geological record.
Writing in the journal Current Biology, today Pyenson’s team presents evidence that the shonisaurs came there to reproduce. The team concludes that the animals migrated long distances to give birth, like some whales do today. The discovery not only represents an example of “convergent evolution,” in which the same traits independently evolve in different species, but also the oldest example of migration in groups to a designated calving ground.
“They’re making quite a convincing case,” says Lene Liebe Delsett, a vertebrate paleontologist at the University of Oslo, Norway, who was not involved in the study. “Ichthyosaurs were the first large marine tetrapods. And throughout the Triassic, they varied quite a lot, so there was a large diversity. It’s just a very interesting period of time to know more about.”
The origin story of the shonisaurs begins with death—a lot of it.
Some 251 million years ago, between the Permian and Triassic periods, Earth’s biggest extinction event annihilated about 95 percent of all marine species. This so-called “Great Dying” mowed down the diverse landscape of creatures in the ocean.Some of the animals that grew back in their place turned out to be weirder and larger than ever before.
The ensuing Triassic started an evolutionary arms race. Prey evolved harder shells and better mobility, predators crunched through ammonite shells and hunted fish better than ever, and so on. Ichthyosaurs, which evolved from terrestrial reptiles into new species of various sizes, partly drove this pressure and quickly dominated the ocean. The Shonisaurus genus, in particular, grew to be some of the largest marine predators around. “They achieved whale sizes before anything else,” says Pyenson.
Pyenson is normally more of a whale guy; he specializes in mammals, which split from reptiles about 325 million years ago. But ancient marine reptiles like those under the order Ichthyosaur bear many similarities to existing marine mammals. Their ancestors came from land, they birthed live young, they had similar flippers, and they are tetrapods, meaning four-limbed. And Pyenson is well versed in this type of mystery. About a decade ago in Atacama, Chile, he and his South American collaborators used 3D mapping and chemical analyses to show that a tight cluster of at least 40 fossilized whales must have died from a toxic algal bloom 7 to 9 million years ago.
by crissly | Dec 14, 2022 | Uncategorized
That is, as we polluted less—heavy industry spun down, flights got canceled, people stopped commuting—we also produced less of the pollutant that normally breaks down methane. It’s a second unfortunate and surprising consequence of cutting pollution: Burning fossil fuels also produces aerosols that bounce some of the sun’s energy back into space, somewhat cooling the climate. While it’s imperative that we decarbonize as quickly as possible, cutting out the beneficial effects of NOx and aerosols has some unintended—and twisted—side effects.
“Burning less fossil fuels will cause there to be less OH radicals in the atmosphere, which will cause methane concentrations to go up,” says Earth scientist George Allen of Virginia Polytechnic Institute and State University, who penned an accompanying commentary on the paper but wasn’t involved in the research. “So that’s going to cut back on the effectiveness of measures to fight global warming.”
This makes it all the more urgent for humanity to take drastic steps to reduce both methane and CO2 emissions, especially considering the alarming degradation of northern lands as the planet warms. The growth of emissions from nature also lends more urgency to the fight to preserve those lands. People are, for instance, draining soggy peatlands and setting them on fire to convert them to farmland, which turns them from carbon sinks into carbon sources. And because the Arctic is warming more than four times faster than the rest of the planet, human development can encroach farther north, churning up carbon sequestered in the soil as people build roads and housing. All of that only exacerbates the problem.
That sort of degradation is blurring the line between human sources of methane and natural ones. “While some sectors are clearly anthropogenic—industry, transportation, landfill, and waste—other ‘natural’ sectors such as polluted waterways and wetlands can be low, moderately, or highly impacted by humans, which in turn can enhance ‘natural’ methane emissions,” says Judith Rosentreter, a senior research fellow at Southern Cross University who studies methane emissions but wasn’t involved in the new research.
Meanwhile, the Arctic region is greening, thanks to new vegetation, which darkens the landscape and further warms the soil. Permafrost—which covers 25 percent of the northern hemisphere’s land surface—is thawing so rapidly that it’s gouging holes in the earth, known as thermokarst, which fill with water and provide the ideal conditions for methane-belching microbes.
“There’s a lot of organic carbon locked in there—it’s like a frozen compost heap in your own garden,” says Torsten Sachs of the GFZ German Research Centre for Geosciences, who wasn’t involved in the new research. “There is a lot of talk and a lot of speculation and a lot of modeling of how much greenhouse gasses are going to come out of these thawing and warming permafrost areas. But as long as you don’t have any real on-the-ground data, you can’t really prove it.”
Sachs has been doing exactly that, venturing into the Siberian tundra for months on end to collect data. In a paper he recently published in Nature Climate Change, he found that methane production every June and July has been rising 2 percent per year since 2004. Interestingly, while this corresponds with significantly higher atmospheric temperatures in the region, it doesn’t seem to correspond with permafrost thaw. Instead, the extra methane may come from wetlands sitting on top of permafrost.
This is the extreme complexity scientists are scrambling to better understand. While the new paper’s modeling can tease apart the methane emitted by humans and nature, on-the-ground data is also necessary to fully understand the dynamics. The ultimate concern is that out-of-control carbon emissions could be initiating climatic feedback loops: We burn fossil fuels, which warms the planet, which thaws permafrost and forms bigger methane-emitting wetlands. That will have serious consequences for the rest of the planet.
Scientists can’t yet say, though, whether we’re already witnessing a feedback loop. This new study focused on 2020, so researchers will need to keep collecting methane data for consecutive years and pinpoint the source of those emissions. But methane emissions were even higher in 2021. “The idea that the warming is feeding the warming is definitely something to be concerned about,” says James France, senior international methane scientist at the Environmental Defense Fund. “That is very difficult to mitigate. So it really reinforces the idea that we have to double down and really focus on mitigation on the areas that we can control.”
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