New study may have found how the Grand Canyon was formed
Published in Geology, the research links Arizona's Meteor Crater, formed 56,000 years ago, to the canyon's development.
The study hypothesises that the meteor impact triggered landslides that blocked the Colorado River, creating a paleolake within the canyon.
This theory explains the presence of 56,000-year-old driftwood and lake sediments found in Stanton's Cave, located 150 feet above the river.
The age of the driftwood matches the geologic age of the asteroid impact and the proposed landslide dam, supporting the connection.
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The Guardian
3 hours ago
- The Guardian
Monarch butterflies' mass die-off in 2024 caused by pesticide exposure
A 2024 mass monarch butterfly die-off in California was probably caused by pesticide exposure, new peer-reviewed research finds, adding difficult-to-obtain evidence to the theory that pesticides are partly behind dramatic declines in monarchs' numbers in recent decades. Researchers discovered hundreds of butterflies that had died or were dying in January 2024 near an overwintering site, where insects spend winter months. The butterflies were found twitching or dead in piles, which are common signs of neurotoxic pesticide poisoning, researchers wrote. Testing of 10 of the insects revealed an average of seven pesticides in each, and at levels that researchers suspect were lethal. Proving that pesticides kill butterflies in the wild is a challenge because it is difficult to find and test them soon after they die. Though the sample size is limited, the authors wrote, the findings provide 'meaningful insight' into the die-off and broader population decline. 'The incident gave us a rare opportunity to directly document pesticide exposure and its impacts on monarchs in the real world,' said Staci Cibotti, the study's lead author, and an entomologist and pesticide program specialist with the Xerces Society for Invertebrate Conservation. She added: 'Even though laboratory studies and population models have shown that pesticides are harmful to monarchs, it can be difficult to capture the impacts of pesticides in the field on wild populations. This study helps to fill that gap.' As much as 90% of the monarch butterfly population in some US regions has been wiped out in recent decades, and evidence has pointed to pesticides, climate crisis and habitat loss as the drivers. The butterflies were found adjacent to the Pacific Grove Monarch Sanctuary, one of about 400 wintering sites along California's coast that are crucial points in the monarchs' migratory and reproductive cycles. Xerces counted about 6,600 butterflies overwintering at Pacific Grove in November 2023. Though an investigation by a state agricultural official did not determine a source of the die-off, pesticide residues on crops, lawns and ornamental flowers are a poisoning risk for monarch larvae, and for adults eating nectar. Pesticide run off in shallow water sources near where high numbers of butterflies collectively drink present a risk for the type of mass die-off at Pacific Grove. All the butterflies showed high levels of the same three pyrethroids, a pesticide class widely used in California on agricultural and residential land. The residential applications are not reported, and Cibotti said the presence of the same types of pyrethroids in all the samples points to a nearby residential exposure as the source. Some of the pyrethroid levels found in the monarchs are known to be lethal, and researchers suspect the combined levels of multiple pesticides also probably contributed. Combinations of pesticides can have a synergistic effect that makes them even more toxic. The solution, Cibotti said, is less pesticides. 'These clustering events occur during especially sensitive phases of the migratory cycle, so reducing pesticide exposure during these times is essential not only to prevent immediate losses, but also to improve the population's chances of rebounding the following spring and support its long-term recovery,' Cibotti said.
The Guardian
4 hours ago
- The Guardian
Scientists slam Trump administration climate report as a ‘farce' full of misinformation
A new Trump administration report which attempts to justify a mass rollback of environmental regulations is chock-full of climate misinformation, experts say. On Tuesday, the Environmental Protection Agency (EPA) announced a proposal to undo the 2009 'endangerment finding', which allows the agency to limit planet-heating pollution from cars and trucks, power plants and other industrial sources. Hours later, the Department of Energy (DOE) published a 150-page report defending the proposal, claiming scientific concern about the climate crisis is overblown. 'Climate change is a challenge – not a catastrophe,' wrote the energy secretary, Chris Wright, in the report's introduction. The esteemed climate scientist Michael Mann said the report was akin to the result he would expect 'if you took a chatbot and you trained it on the top 10 fossil fuel industry-funded climate denier websites'. The energy department published the report hours after the EPA announced a plan to roll back 2009's 'endangerment finding', a seminal ruling that provided the legal basis for the agency to regulate climate-heating pollution under the Clean Air Act. If finalized, the move would topple virtually all US climate regulation. In a Fox News interview, Wright claimed the report pushed back on the 'cancel culture Orwellian squelching of science'. But Naomi Oreskes, a history of science professor at Harvard University and expert in climate misinformation, said its true purpose was to 'justify what is a scientifically unjustifiable failure to regulate fossil fuels'. 'Science is the basis for climate regulation, so now they are trying to replace legitimate science with pseudoscience,' she said. The attack on the research underpinning the endangerment finding – which says greenhouse gases endanger public health and welfare – comes as part of Trump's 'drill, baby, drill' agenda to boost fossil fuels, which are the primary cause of global warming. 'This is an agenda to promote fossil fuels, not to protect public health and welfare or the environment,' said Rachel Cleetus, a director at climate and science non-profit Union of Concerned Scientists who was an author on the sixth US national climate assessment. Asked about scientists' assertions that the new report is rife with misinformation, an energy department spokesperson, Ben Dietderich, said: 'This report critically assesses many areas of ongoing scientific inquiry that are frequently assigned high levels of confidence – not by the scientists themselves but by the political bodies involved, such as the United Nations or previous presidential administrations.' But the UN's Intergovernmental Panel on Climate Change (IPCC) produces what is widely considered the gold standard compendium of climate science, compiled by a huge multinational team of scientists, peer-reviewed and agreed to by every national government. The latest IPCC synthesis report, released two years ago, was a vast undertaking involving 721 volunteer scientists around the world. It states that it is 'unequivocal' that human activity has heated the planet, which has 'led to widespread adverse impacts and related losses and damages to nature and people'. By contrast, the Trump administration report was crafted by five handpicked scientists who are seen as having fringe or contrarian views by mainstream climate scientists, with no peer review. The experts behind the report have previously denied being climate deniers. The energy department did not respond to a question about the authors. 'This report had five authors and was rushed over four months, and would not pass muster in any traditional scientific peer review process,' said Zeke Hausfather, a research scientist at the climate non-profit Berkeley Earth, who called the paper a 'farce'. Wright, the energy secretary, insisted he had not steered the report's conclusions, while Judith Curry, one of the report authors, said in a blogpost she hoped the document would push climate science 'away from alarmism and advocacy'. Mainstream climate scientists, however, condemned the findings as distorted and inaccurate. 'This is a report written by a couple of scientists who are outliers in their arguments for climate change,' said Natalie Mahowald, a climate scientist at Cornell University. 'This document does in no way depreciate the value of previous assessments, but rather just cherrypicks the literature to pretend to create a new review.' Mahowald said the lack of peer review meant it was 'obviously not as robust' as the IPCC report or the US government's periodic national climate assessment, which the Trump administration recently took offline. The latest national climate assessment, compiled by a dozen government agencies and outside scientists in 2023, concluded that the 'effects of human-caused climate change are already far-reaching and worsening across every region of the United States' 'If almost any other group of scientists had been chosen, the report would have been dramatically different,' Andrew Dessler, a climate researcher at Texas A&M University, said of the new report. 'The only way to get this report was to pick these authors.' Hausfather agreed that the authors' work 'might represent their views but is not consistent with the broader scientific literature on climate change'. He was among the scientists whose work the authors cited. The new paper includes a chart from a 2019 report which he led, claiming it demonstrates how climate models 'consistently overestimated observations' of atmospheric carbon. But Hausfather's research actually showed that climate models have performed well. 'They appear to have discarded the whole paper as not fitting their narrative, and instead picked a single figure that was in the supplementary materials to cast doubt on models when the whole paper actually confirmed how well they have performed in the years after they were published,' he said. The energy department did not respond to a request for comment about Hausfather's concerns. That approach to research seems to underpin the entire paper, said Hausfather, who is also the climate research lead at tech company Stripe. 'This is a general theme in the report; they cherrypick data points that suit their narrative and exclude the vast majority of the scientific literature that does not,' he said. Dessler said scientists are obliged to engage with the full range of evidence, even if it contradicts their initial assumptions. Ignoring this principle 'can rise to the level of scientific misconduct', he said. 'The report they produced should be thought of as a law brief from attorneys defending their client, carbon dioxide,' Dessler said. 'Their goal is not to weigh the evidence fairly but to build the strongest possible case for CO2's innocence.' The lack of peer review in the administration's report led to conclusions that deviated, sometimes wildly, from the scientific literature. Many of its claims are based on long-debunked research long promoted by climate deniers, said Mann. 'It is shop worn, decades-old, discredited climate denier talking points, dressed up in the clothing of some sensible new set of revelations,' he said. 'What's different is that it has the imprimatur of the EPA and the federal government now.' The report, for instance claims that warming trends have been overstated, despite evidence to the contrary. It was published as extreme heat is affecting millions of Americans. 'They're literally trying to tell us not to believe what we see with our own two eyes … and instead buy into their denialist framing that rejects not just the science, but what is plainly evident if you look out your window,' said Mann. The authors also write that ocean acidification is occurring 'within the range of natural variability' and is beneficial for marine life despite the ocean's acidic levels currently being the highest since 14m years ago, a time when a major extinction event was occurring. And the report references the apparent health of Australia's Great Barrier Reef, which it says 'has shown considerable growth in recent years'. The reef was recently hit by its sixth mass bleaching event since 2016, a devastating phenomenon for corals in which they whiten and sometimes die due to high sea temperatures. No widespread bleaching events were recorded on the reef before 1998. The report is 'tedious' and at times 'truly wearisome', according to Bob Kopp, a climate scientist at Rutgers University. Kopp recently worked on a paper showing how rising temperatures and drought will worsen crop yields, counter to the report's claims that crops will flourish with extra carbon dioxide in the atmosphere. 'Carbon dioxide fertilization is largely irrelevant to how increasingly extreme heat and intense drought will impact crop yields,' Kopp said. 'As a former department of energy fellow, I'm embarrassed by this report.'
The Independent
6 hours ago
- The Independent
Judge allows the National Science Foundation to withhold hundreds of millions of research dollars
The National Science Foundation can continue to withhold hundreds of millions of dollars from researchers in several states until litigation aimed at restoring it plays out, a federal court ruled Friday. U.S. District Judge John Cronan in New York declined to force the NSF to restart payments immediately, while the case is still being decided, as requested by the sixteen Democrat-led states who brought the suit, including New York, Hawaii, California, Colorado and Connecticut. In his ruling, Cronan said he would not grant the preliminary injunction in part because it may be that another court, the Court of Federal Claims, has jurisdiction over what is essentially a case about money. He also said the states failed to show that NSF's actions were counter to the agency's mandate. The lawsuit filed in May alleges that the National Science Foundation's new grant-funding priorities as well as a cap on what's known as indirect research expenses 'violate the law and jeopardize America's longstanding global leadership in STEM.' Another district court had already blocked the the cap on indirect costs — administrative expenses that allow research to get done like paying support staff and maintaining equipment. This injunction had been requested to restore funding to the grants that were cut. In April, the NSF announced a new set of priorities and began axing hundreds of grants for research focused on things like misinformation and diversity, equity and inclusion. Researchers who lost funding also were studying artificial intelligence, post-traumatic stress disorder in veterans, STEM education for K-12 students and more. Researchers were not given a specific explanation for why their grants were canceled, attorney Colleen Faherty, representing the state of New York, said during last month's hearing. Instead, they received boilerplate language stating that their work 'no longer effectuates the program goals or agency priorities." NSF has long been directed by Congress to encourage underrepresented groups like women and people with disabilities to participate in STEM. According to the lawsuit, the science foundation's funding cuts already halted efforts to train the next generation of scientists in fields like computer science, math and environmental science. A lawyer for the NSF said at the hearing that the agency has the authority to fund whatever research it deems necessary — and has since its inception in 1950. In the court filing, the government also argued that its current priorities were to 'create opportunities for all Americans everywhere' and 'not preference some groups at the expense of others, or directly/indirectly exclude individuals or groups.' The plaintiff states are trying to 'substitute their own judgement for the judgement of the agency," Adam Gitlin, an attorney for the NSF, said during the hearing. The science foundation is still funding some projects related to expanding representation in STEM, Cronan wrote in his ruling. Per the lawsuit filed in May, for example, the University of Northern Colorado lost funding for only one of its nine programs focused on increasing participation of underrepresented groups in STEM fields. The states are reviewing the decision, according to spokespeople from the New York and Hawaii attorney general offices. The National Science Foundation declined to comment. ___ The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute's Department of Science Education and the Robert Wood Johnson Foundation. The AP is solely responsible for all content.
