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    Spotting climate misinformation with AI requires expertly trained models

    Conversational AI chatbots are making climate misinformation sound more credible, making it harder to distinguish falsehoods from real science. In response, climate experts are using some of the same tools to detect fake information online.

    But when it comes to classifying false or misleading climate claims, general-purpose large language models, or LLMs­ — such as Meta’s Llama and OpenAI’s GPT-4­ — lag behind models specifically trained on expert-curated climate data, scientists reported in March at the AAAI Conference on Artificial Intelligence in Philadelphia. Climate groups wishing to use commonly available LLMs in chatbots and content moderation tools to check climate misinformation need to carefully consider the models they use and bring in relevant experts to guide the training process, the findings show. More

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    A lush, green Arabian Desert may have once linked Africa and Asia

    The Arabian Desert, today the largest expanse of windswept sand dunes on Earth, experienced recurring periods of humidity millions of years ago, researchers report April 9 in Nature. The study may explain how mammals at that time survived the trek across what is now a vast and barren landscape.

    The findings come from mineral formations deep inside caves beneath the Arabian Peninsula. These speleothems — stalagmites and stalactites, formed by dripping rainwater — provide evidence that the region underwent repeated humid periods stretching back nearly 8 million years. The scientists used uranium dating to precisely determine the ages of speleothem samples, offering one of the oldest climate records for the region. More

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    Solar geoengineering moves into the spotlight as climate concerns grow

    Earth’s average temperature is continuing to tick inexorably upward as the world’s nations stall at reducing their atmosphere-warming emissions. In the face of that grim future, strategies to try to turn down the planet’s thermostat are gaining traction. One strategy in particular — solar geoengineering, which aims to cool the planet by reflecting solar radiation back into space — may be having a moment in the sun.

    Depending on whom you ask, it’s potentially highly dangerous, highly promising or highly uncertain. There aren’t any real guidelines. But, with the future of emissions restrictions also highly uncertain, some researchers say solar geoengineering needs to be on the table. More

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    The ozone layer shields life on Earth. We’ll soon lose a key way to monitor its health

    Humankind will soon lose a great deal of vigilance over the ozone layer, which shields life on Earth from harmful solar radiation.

    The impending loss of NASA’s Aura and the Canadian Space Agency’s SCISAT satellites threatens scientists’ ability to closely monitor compounds that destroy ozone and alter stratospheric circulation. With no planned missions to replace either satellite, a data desert in the stratosphere appears imminent, researchers warn in the March Bulletin of the American Meteorological Society. More

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    Splitting seawater offers a path to sustainable cement production

    A new cement-making process could shift production from being a carbon source to a carbon sink, creating a carbon-negative version of the building material, researchers report March 18 in Advanced Sustainable Systems. This process might also be adaptable to producing a variety of carbon-stashing products such as paint, plaster and concrete.

    Cement production is a huge contributor to global carbon dioxide emissions, responsible for about 8 percent of total CO2 emissions, making it the fourth-largest emitter in the world. Much of that carbon comes from mining for the raw materials for concrete in mountains, riverbeds and the ocean floor. More

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    Physicists are mostly unconvinced by Microsoft’s new topological quantum chip

    ANAHEIM, CALIF. — At the world’s largest gathering of physicists, a talk about Microsoft’s claimed new type of quantum computing chip was perhaps the main attraction. 

    Microsoft’s February announcement of a chip containing the first topological quantum bits, or qubits, has ignited heated blowback in the physics community. The discovery was announced by press release, without publicly shared data backing it up. A concurrent paper in Nature fell short of demonstrating a topological qubit. Microsoft researcher Chetan Nayak, a coauthor on that paper, promised to provide solid evidence during his March 18 talk at the American Physical Society’s Global Physics Summit. More

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    JWST spots the earliest sign yet of a distant galaxy reshaping its cosmic environs

    The James Webb Space Telescope has caught a distant galaxy blowing an unexpected bubble in the gas around it, just 330 million years after the Big Bang.

    The galaxy, dubbed JADES-GS-z13-1, marks the earliest sign yet spotted of the era of cosmic reionization, a transformative period in the universe’s history when the first stars and galaxies began to reshape their environment, astronomers report in the March 27 Nature.

    “It definitely puts a pin in the map of the first point where [reionization] very likely has already started,” says astrophysicist Joris Witstok at the University of Copenhagen. “No one had predicted that it would be this early” in the universe’s history. More

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    A map of 14 million galaxies and quasars deepens a dark energy mystery

    ANAHEIM, Calif. — Change is in the air. New data strengthen a hint that dark energy, long thought to be constant force in the universe, might change over time.Dark energy explains the observation that the universe’s expansion rate is accelerating. But its origins are unknown. It’s typically expected to have constant density across the billions of years of the universe’s history. So when researchers from the Dark Energy Spectroscopic Instrument, or DESI, reported in 2024 that dark energy might vary over time based on their first year of data, it shook cosmology to its core.

    Many scientists expected that the standard picture would prevail with additional data from DESI. But that hasn’t happened. Instead, with three years of DESI data, the preference for a changing, or dynamical dark energy has grown. More