Rivers can fuel hurricanes, new USF study finds
Why it matters: The findings add to growing evidence that river plumes can exacerbate coastal storms, underscoring the need to incorporate them into hurricane forecasts.
The big picture: Hurricane Idalia surged from Category 1 to Category 4 in less than 24 hours as it neared Florida's Big Bend in August 2023, a phenomenon known as rapid intensification.
Hurricanes Helene and Milton did the same. Each time, the abrupt spike made it harder for forecasters to assess the storms' impact.
Zoom in: Researchers studied a large plume of freshwater that stretched from the Mississippi River to the Florida Keys, and found that where it met saltwater, ideal conditions for rapid intensification were created.
The freshwater from rivers along the Gulf Coast created a thick surface layer that did not mix with the cooler saltwater below, keeping the surface water warm and potentially fueling storms.
What they're saying: "Our study demonstrates the value of considering the influence of river plumes on storm intensification," said Chuanmin Hu, a professor of oceanography at USF and one of the study's authors.
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Newsweek
a day ago
- Newsweek
Map Shows Where 100-Year Floods Have Hit Across the US Over Past Year
Based on facts, either observed and verified firsthand by the reporter, or reported and verified from knowledgeable sources. Newsweek AI is in beta. Translations may contain inaccuracies—please refer to the original content. The term "100-year flood" implies that the event is a rare occurrence; however, dozens of such storms have inundated the United States over the past year alone, prompting concern that they are occurring more frequently as the Earth's climate continues to warm. Why It Matters Flooding is the second-deadliest weather hazard in the U.S., next to extreme heat. Devastating flood events have made headlines numerous times this year, including a 1,000-year atmospheric river event that hit the Midwest and South in April and the deadly floods that inundated Central Texas over the July 4th weekend. The frequency of such flooding rainstorms, which often go hand-in-hand with death and destruction, is alarming. What's even more concerning is that AccuWeather meteorologist Alex DaSilva told Newsweek that these events are happening more frequently. What To Know In 2024, dozens of 100-year rainstorms struck the U.S. Each point is marked on the map below, created by Colorado State University. The points marking each event are widespread, with only a few states escaping unscathed. Last year wasn't a one-time occurrence, either. This year is also "shaping up to be one of the most flood-impacted summers on record in the United States," AccuWeather reported. A map from Colorado State University shows where 100-year rainstorm events were documented in 2024. A map from Colorado State University shows where 100-year rainstorm events were documented in 2024. Colorado State University What Is a 100-Year Flood? The United States Geological Service (USGS) describes the term "100-year flood" as an attempt "to simplify the definition of a flood that statistically has a 1-percent chance of occurring in any given year." Where Did 100-Year Rainstorms Hit in 2024? On the CSU map, countless points pepper the Eastern Seaboard around North Carolina and South Carolina after Hurricane Helene struck in September. Others show the devastating impact of the summer monsoon season in New Mexico, which caused deserts to flood and cars to become stranded as water washed over a highway. Vermont faced catastrophic floods in late July. Central Texas, known as Flash Flood Alley, experienced several 100-year rainstorms last year, as did Florida, with a scattershot of points dated as occurring during the Atlantic hurricane season. There was also an onslaught of precipitation that hit South Dakota in June 2024, as well as a similar storm that measured as a 100-year event at several locations in Missouri in November, among others. Only a few states emerged unscathed, including Iowa, Wisconsin, Oregon, Washington, and Massachusetts, but most of the U.S. experienced some form of severe flooding precipitation last year. Why Are 100-Year Floods Occurring More Frequently? The map's creator, Russ Schumacher, a professor of atmospheric sciences at CSU and a CSU climatologist, told Newsweek that improved technology, such as radar, provides better access to data, which can make it seem as if the flood events are happening more frequently. However, he also stressed the impact of climate change. "The physics of climate change tells us that we should see these extreme events more frequently," he said. As the atmosphere grows warmer through global warming, its ability to hold moisture increases, DaSilva told Newsweek. "This is why in the wintertime, we typically don't see too much flash flooding in the wintertime," DaSilva said. "It's too cold, and there's snow, of course, but it's hard to get the moisture content you need for heavy rain events in the wintertime because it's cooler out. In the summertime obviously the temperature is above freezing, but the atmosphere can hold more water content. There's more moisture to squeeze out." Which States Have Increased Flood Risk? As the atmosphere's ability to hold moisture increases, DaSilva told Newsweek that states in the Ohio and Tennessee valleys are becoming wetter, while areas like California are becoming drier. What People Are Saying AccuWeather meteorologist Alex DaSilva told Newsweek: "When the atmosphere is getting warmer as a what it's doing is making summer warmer and the shoulder seasons warmer as well. What's happening is those seasons, especially in the summertime, the [atmosphere's] ability to hold more moisture is going up as well." DaSilva added: "It doesn't guarantee we will see more rain over a certain area, it rains, it's going to rain heavier." The USGS in a webpage about 100-year flood events: "In other words, over the course of 1 million years, these events would be expected to occur 10,000 times. But, just because it rained 10 inches in one day last year doesn't mean it can't rain 10 inches in one day again this year." What Happens Next As the probability of heavy rain events increases, people are advised to have a flood plan in place before such an event occurs in their area. People should also never drive on a flooded roadway, as most flood-related deaths occur in vehicles.
Atlantic
3 days ago
- Atlantic
The Sea Slug Defying Biological Orthodoxy
This week, a friend sent me our horoscope—we're both Gemini—from Seven Days, a beloved Vermont weekly, because, improbably, it was about the sea slug I'd been telling her about just days before. 'The sea slug Elysia chlorotica is a small, unassuming creature that performs a remarkable feat: It eats algae and steals its chloroplasts, then incorporates them into its own body,' the horoscope explained. Years ago I had incorporated this fact into my own view of the world, and it had changed my understanding of the rules of biology. This particular slug starts life a brownish color with a few red dots. Then it begins to eat from the hairlike strands of the green algae Vaucheria litorea: It uses specialized teeth to puncture the alga's wall, and then it slurps out its cells like one might slurp bubble tea, each bright-green cellular boba moving up the algal straw. The next part remains partially unexplained by science. The slug digests the rest of the cell but keeps the chloroplasts—the plant organelles responsible for photosynthesis—and distributes these green orbs through its branched gut. Somehow, the slug is able to run the chloroplasts itself and, after sucking up enough of them, turns a brilliant green. It appears to get all the food it needs for the rest of its life by way of photosynthesis, transforming light, water, and air into sugar, like a leaf. The horoscope took this all as a metaphor: Something I'd 'absorbed from another' is 'integrating into your deeper systems,' it advised. 'This isn't theft, but creative borrowing.' And in that single line, the horoscope writer managed to explain symbiosis—not a metaphor at all, but an evolutionary mechanism that may be more prevalent across biology than once thought. Elysia chlorotica is a bewitching example of symbiosis. It is flat, heart-shaped, and pointed at the tail, and angles itself toward the sun. Its broad surface is grooved by a web of veins, like a leaf's is. Ignore its goatish head, and you might assume this slug was a leaf, if a particularly gelatinous one. Sidney Pierce, a marine biologist retired from the University of South Florida, remembers his surprise when a grad student brought a specimen into his office in the Marine Biological Laboratory at Woods Hole, on Cape Cod, more than two decades ago. Photosynthesis requires specialized equipment and chemistry, which animals simply do not have—'yet here was an animal that's figured out how to do it,' he told me. He spent the next 20-odd years trying to find the mechanism. 'Unfortunately, I didn't get all the way to the end,' he said. No one has, as my colleague Katherine J. Wu has written. The algae and the slug may have managed some kind of gene transfer, and over time, produced a new way of living, thanks not to slow, stepwise evolution—the random mutation within a body—but by the wholesale transfer of a piece of code. A biological skill leaked out of one creature into another. All of us are likely leakier than we might assume. After all, every cell with a nucleus, meaning all animal and plant cells, has a multigenetic heritage. Mitochondria—the organelles in our cells responsible for generating energy—are likely the product of an ancient symbiosis with a distant ancestor and a microbe, and have their own separate DNA. So we are walking around with the genetic material of some other ancient life form suffused in every cell. And the earliest ancestor of all plants was likely the product of a fusion between a microbe and a cyanobacterium; plants' photosynthesizing organelles, too, have distinct DNA. Lynn Margulis, the biologist who made the modern case for this idea, was doubted for years until new genetic techniques proved her correct. Her conviction about the symbiotic origins of mitochondria and chloroplasts was a monumental contribution to cell biology. But Margulis took her theory further; in her view, symbiosis was the driving force of evolution, and many entities were likely composites. Evolution, then, could be traced not only through random mutation, but by combination. 'Life did not take over the globe by combat, but by networking. Life forms multiplied and complexified by co-opting others, not just by killing one another,' she wrote, with her son, in 1986. This remains pure conjecture, and an exaggeration of the role of symbiosis beyond what mainstream evolutionary theory would support; random mutation is still considered the main driver of speciation. Yet more scientists now wonder if symbiosis may have played a larger role in the heritage of many species than we presently understand. Phillip Cleves, a geneticist at the Carnegie Institution for Science who studies the symbiotic relationship between corals and their algae symbionts, told me how, as an undergraduate, he was blown away by the fact that corals' alliance with algae made possible ecosystems—coral reefs—that support a quarter of all known marine life. The algae cells live, whole, inside coral cells, and photosynthesize as normal, sustaining the coral in nutrient-poor tropical waters. 'I realize now that that type of interaction between organisms is pervasive across the tree of life,' he said. It's probable that the ancestors of all eukaryotes were more influenced by bacteria in their environments than modern evolutionary theory has accounted for. 'All animals and plants likely require interactions with microbes, often in strong, persistent symbiotic associations,' Margaret McFall-Ngai, a leading researcher of the role of microbes in animal development, wrote in 2024. These interactions, she argued, are so fundamental to life that the animal immune system should perhaps be thought of as a sort of management system for our many microbial symbionts. Although biology has been slow to recognize symbiosis's significance, she thinks this line of research should now take center stage, and could alter how all stripes of biologists think about their work. Cleves, too, sees himself as working to build a new field of science, by training people on how to ask genetic questions about symbiotic relationships in nature: When I called him, he was preparing to teach a four-week course at the Marine Biological Laboratory in Woods Hole on exactly that. Genomic research has only relatively recently been cheap enough to apply it routinely and broadly to all sorts of creatures, but now scientists can more easily ask: How do animals' interactions with microbes shape the evolution of individual species? And how does that change dynamics in an ecosystem more broadly? Elysia chlorotica is also a lesson in how easily the boundaries between an organism and its environment can be traversed. 'Every time an organism eats, a whole wad of DNA from whatever it's eating passes through the animal. So DNA gets transferred all the time from species to species,' Pierce told me. Most times it doesn't stick, but on the rare occasions when it does, it can reroute the fate of a species. 'I think it happens more than it's recognized, but a lot of times it's hard to recognize because you don't know what you're looking for. But in these slugs, it's pretty obvious,' he said. They're bright green. Still, attempts to understand what is happening inside Elysia chlorotica have mostly fallen short. Scientists such as Pierce presume that, over time, elements of the algal genome have been transferred to the slug, allowing it to run photosynthesis, yet they have struggled to find evidence. 'It's very hard to find a gene if you don't know what you're looking for,' Pierce said—plus, slug DNA is too muddled to parse a lot of the time. Slugs are full of mucus, which can ruin samples, and because the chloroplasts are embedded inside the slug cells, many samples of slug DNA end up picking up chloroplast DNA too. After years of trying, and at least one false start by a different lab, Pierce and his colleagues did manage to find a gene in the slug that was involved with chloroplast repair, hinting that a genetic transfer had occurred, and offering a clue as to how the animal manages to keep the plant organelles alive. But another research team showed that related species of photosynthesizing slugs can survive for months deprived of sunlight and actual food: They may simply be hardy. Why, then, if not to make nutrients, might the slugs be photosynthesizing? Perhaps for camouflage. Or perhaps they're stashing chloroplasts, which themselves contain useful fats and proteins, as food reserves. (Pierce, for one, is skeptical of those explanations.) Whatever benefit Elysia chlorotica derives from the chloroplasts, there couldn't be a leakier creature. It crosses the divide between plant and animal, one species and another, and individual and environment. I first read about the slug in a book titled Organism and Environment by Sonia Sultan, an evolutionary ecologist at Wesleyan University, in which she forwards the argument that we should be paying more attention to how the environment influences the way creatures develop, and how those changes are passed generationally, ultimately influencing the trajectory of species. While Elysia chlorotica is an extreme example of this, a version of it happens to us, and our bodies, all the time. Encounters with the bacteria around us reshape our microbiomes, which in turn affect many aspects of our health. Encounters with pollution can reroute the trajectory of our health and even, in some cases, the health of our offspring. Researchers think access to healthy foods—a factor of our environments—can modify how our genes are expressed, improving our lives in ways that scientists are just beginning to understand. We are constantly taking our environment in, and it is constantly transforming us.
The Hill
7 days ago
- The Hill
Without weather forecasters, our canaries in the storm, expect disaster
Before modern forecasting, hurricanes were mass casualty events. The 1900 Galveston Hurricane killed over 8,000 people, wiping out an entire city with a 15-foot storm surge. Less than a century ago, Hurricane Okeechobee killed over 2,500 Floridians in a tragedy that today would be largely preventable. We've come a long way since the days when hurricanes struck without warning. I know, because I helped develop the systems that save countless lives and give communities time to prepare. That was my job until February, when I was terminated by President Trump and Elon Musk's Department of Government Efficiency alongside hundreds of other scientists at the National Oceanic and Atmospheric Administration. Since then, I have continued my work in hurricane forecasting through Cooperative Institute research; however, the cuts left deep holes across NOAA's forecasting teams that've not been filled. This purge isn't 'cutting waste' — it is dismantling America's hurricane monitoring systems. At the National Oceanic and Atmospheric Administration, I worked on the next-generation Hurricane Analysis and Forecast System. This system enabled emergency managers to issue timely evacuation orders during life-threatening hurricanes like Helene and Milton, helping prevent thousands of potential fatalities. Yet even with cutting-edge forecasting, Helene revealed new, urgent challenges. In the last decade, freshwater flooding surpassed storm surge as the leading cause of hurricane-related deaths. Helene's victims were coastal residents and mountain communities, caught unprepared by catastrophic inland flooding. Dozens more died — victims of power outages, delayed medical care and collapsed infrastructure in the days after the storm passed. If our warning systems don't evolve to keep pace with rapidly changing storms, Helene's damage may seem merciful compared to future disasters. Precisely when adaptation is most urgent, political decisions have systematically dismantled our protective infrastructure. Key vacancies remain across NOAA's local forecast offices, satellite operations and modeling teams — many of which are already stretched thin this hurricane season. Without continuous investment in modeling and surveillance, hurricane season, which officially began June 1, will become even deadlier and harder to predict. DOGE's decimation of the forecasting workforce unravels a century of progress in hurricane survival rates. While the full impact of these cuts won't be seen overnight, the damage will compound the longer these positions go unfilled. The National Oceanic and Atmospheric Administration isn't just a research agency; it's America's first line of defense against natural disasters. Forecasting is the foundation of all response efforts. While scientists aren't knocking doors with evacuation orders ourselves, we're the ones telling first responders when, if, and whose doors they should knock on. When NOAA functions at full capacity, emergency managers have the tools they need to prepare their communities. NOAA's remaining scientists and National Weather Service forecasters will give their all this hurricane season to deliver the most accurate forecasts possible, but dedication can't make up for a system that's been hollowed out, and grit can only hold together this critical system for so long. Privatizing these forecasting services creates a dangerous 'pay-to-play' model for life-saving information. This approach wouldn't just create barriers for low-income families; it would hamstring small municipalities and volunteer emergency services trying to protect their communities. The private sector cannot fill this void. The National Weather Service processes over 6 billion observations daily and issues approximately 1.5 million forecasts and 50,000 warnings annually. No private entity possesses infrastructure that can match this scale and reliability. There is a better path forward. By recommitting to public science and restoring forecasters' positions, we can build systems that adapt to changing storms, accurately track flood zones and storm paths, and provide both inland and coastal communities with the advanced warning they need to stay safe. We owe this to every family who will face the next Helene or Milton. Congress must act urgently to restore NOAA's full operational capacity and reject all efforts to privatize these essential services. The FY26 federal budget proposes a $1.3 billion cut to NOAA's core operations, such as satellite programs essential to forecasting, programs supporting climate modeling and even public education. NOAA can't issue life-saving warnings if its data stream has gone dark. And the research that drives improvements in modeling and forecasting is threatened if some of the budget proposals come to fruition. There have been some positive developments from Congress. The House Republicans' fiscal 2026 Commerce-Justice-Science spending bill, announced on Monday, proposes a much-smaller cut of $387 million, bringing the NOAA budget to $5.8 billion. While it's a modest improvement, it still does not fully cover the financial needs of an agency tasked with protecting hundreds of millions of Americans. Hurricane forecasting shouldn't be treated like a luxury or a political football. It's public infrastructure that's as essential as our power grids or water systems. Storm surges don't check voter registrations before flooding homes, and hurricanes won't stop based on who occupies the White House. Without urgent action in this year's budget, we risk turning the worst-case scenario into reality. The question isn't whether the storms are coming. It's whether we'll be ready when they do.
