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    The axolotl is endangered in the wild. A discovery offers hope

    Despite capturing hearts around the world, the wild axolotl — an aquatic salamander with feathery frills and a soft smile — faces extinction. Fortunately, for both axolotls and their fans, a new conservation method shows promise.

    In captivity, axolotls abound as household pets and research subjects. But wild axolotls, endemic to a single lake in Mexico, are critically endangered due to degradation of their native wetlands, with only 50 to 1,000 individuals left in the wild. Introducing captive-bred axolotls to restored and artificial wetlands may be a promising option for conserving these charismatic critters, researchers report April 30 in PLOS One. More

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    Wetland bacteria could make more methane in a warming world

    Warming temperatures may cause methane emissions from wetlands to rise — by helping methane-producing bacteria thrive. Higher temperatures favor the activity of wetland soil microbes that produce the potent greenhouse gas, at the expense of other microbes that can consume it, researchers report April 23 in Science Advances.

    The scientists, led by microbiologist Jaehyun Lee of the Korea Institute of Science and Technology in Seoul, conducted a summer field study in coastal wetlands near the Chesapeake Bay, analyzing soil conditions in a set of marshy plots with differing environmental conditions. The findings may offer clues to a puzzling and worrisome spike in wetland emissions of methane over the last decade. More

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    Earth’s landmasses lost trillions of tons of water this century

    Earth’s landmasses are holding onto a lot less water than they used to — and this loss is not just due to melting ice sheets. Terrestrial water storage, which includes water in underground aquifers, lakes, rivers and the tiny pore spaces within soil, declined by trillions of metric tons in the early 21st century, researchers report in the March 28 Science.

    This sharp decrease in freshwater stores is driven by rising temperatures on land and in the oceans, which in turn are linked to an increased global incidence of drought. And given the projected warming of the planet, this trend isn’t likely to change any time soon, say geophysicist Ki-Weon Seo of Seoul National University and colleagues. More

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    Hidden Antarctic lakes could supercharge sea level rise

    Beneath the great, white expanse of the Antarctic Ice Sheet, a mysterious realm of streams and lakes lies out of sight. Much about this hidden water world remains poorly understood. But a new study suggests that if scientists continue to overlook it, they might greatly underestimate global sea level rise.

    Factoring this subglacial water into computer simulations could boost projections of sea level rise over the next two centuries by about two meters, researchers report April 7 in Nature Communications. For context, scientists estimate that climate warming has raised sea levels by about 0.2 meters over the last century. More

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    Fires in the Amazon forest may melt sea ice in Antarctica

    Soot from forest fires in the Amazon might play a role in the melting of faraway ice in Antarctica.

    For decades, scientists have known that black carbon from burning fossil fuels or forests accelerates ice melt in different parts of the world. According to remote sensing researcher Sudip Chakraborty, the slash-and-burn practices encouraged by Brazil’s former president Jair Bolsonaro, who held office from 2019 to 2023, inspired his team to investigate whether black carbon from the Amazon affected ice melt in Antarctica. More

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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