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Categories: Geoscience: Geography, Paleontology: Fossils
Published Vitamin B12 adaptability in Antarctic algae has implications for climate change, life in the Southern Ocean
(via sciencedaily.com) Original source The algae P. antarctica has two forms of the enzyme that makes the amino acid methionine, one needing B12, and one that is slower, but doesn't need it. This means it has the ability to adapt and survive with low B12 availability. The presence of the MetE gene in P. antarctica gives the algae the ability to adapt to lower vitamin B12 availability, giving it a potential advantage to bloom in the early austral spring when bacterial production is low. P. antarctica takes in the CO2 and releases oxygen through photosynthesis. Understanding its ability to grow in environments with low vitamin B12 availability can help climate modelers make more accurate predictions.
Published In a warming world, climate scientists consider category 6 hurricanes
(via sciencedaily.com) Original source For more than 50 years, the National Hurricane Center has used the Saffir-Simpson Windscale to communicate the risk of property damage; it labels a hurricane on a scale from Category 1 (wind speeds between 74 -- 95 mph) to Category 5 (wind speeds of 158 mph or greater). But as increasing ocean temperatures contribute to ever more intense and destructive hurricanes, climate scientists wondered whether the open-ended Category 5 is sufficient to communicate the risk of hurricane damage in a warming climate.
Published Rare 3D fossils show that some early trees had forms unlike any you've ever seen
(via sciencedaily.com) Original source In the fossil record, trees typically are preserved with only their trunks. They don't usually include any leaves to show what their canopies and overall forms may have looked like. In a new study, researchers describe fossilized trees from New Brunswick, Canada with a surprising and unique three-dimensional crown shape.
Published Permafrost alone holds back Arctic rivers -- and a lot of carbon
(via sciencedaily.com) Original source A new study provides the first evidence that the Arctic's frozen soil is the dominant force shaping Earth's northernmost rivers, confining them to smaller areas and shallower valleys than rivers to the south. But as climate change weakens Arctic permafrost, the researchers calculate that every 1 degree Celsius of global warming could release as much carbon as 35 million cars emit in a year as polar waterways expand and churn up the thawing soil.
Published Tidal landscapes a greater carbon sink than previously thought
(via sciencedaily.com) Original source Mangroves and saltmarshes sequester large amounts of carbon, mitigating the greenhouse effect. New research shows that these environments are perhaps twice as effective as previously thought.
Published Climate change: Fungal disease endangers wheat production
(via sciencedaily.com) Original source Climate change poses a threat to yields and food security worldwide, with plant diseases as one of the main risks. An international team of researchers has now shown that further spread of the fungal disease wheat blast could reduce global wheat production by 13% until 2050. The result is dramatic for global food security.
Published Engineers unmask nanoplastics in oceans for the first time, revealing their true shapes and chemistry
(via sciencedaily.com) Original source Millions of tons of plastic waste enter the oceans each year. The sun's ultraviolet light and ocean turbulence break down these plastics into invisible nanoparticles that threaten marine ecosystems. In a new study, engineers have presented clear images of nanoplastics in ocean water off the coasts of China, South Korea and the United States, and in the Gulf of Mexico. These tiny plastic particles, which originated from such consumer products as water bottles, food packaging and clothing, were found to have surprising diversity in shape and chemical composition.
Published Did dementia exist in ancient Greek and Rome?
(via sciencedaily.com) Original source Did the ancient Greeks and Romans experience Alzheimer's? Medical texts from 2,500 years ago rarely mention severe memory loss, suggesting today's widespread dementia stems from modern environments and lifestyles, a new analysis shows.
Published Source rocks of the first real continents
(via sciencedaily.com) Original source Geoscientists have uncovered a missing link in the enigmatic story of how the continents developed- - a revised origin story that doesn't require the start of plate tectonics or any external factor to explain their formation. Instead, the findings rely solely on internal geological forces that occurred within oceanic plateaus that formed during the first few hundred million years of Earth's history.
Published Unprecedented ocean heating shows risks of a world 3°C warmer
(via sciencedaily.com) Original source New research examines the causes of the record-breaking ocean temperatures witnessed in 2023.
Published Greenland is a methane sink rather than a source
(via sciencedaily.com) Original source Researchers have concluded that the methane uptake in dry landscapes exceeds methane emissions from wet areas across the ice-free part of Greenland. The results of the new study contribute with important knowledge for climate models. The researchers are now investigating whether the same finding applies to other polar regions.
Published As sea otters recolonize California estuary, they restore its degraded geology
(via sciencedaily.com) Original source As sea otters recolonize a California estuary, they are restoring its degraded geology by keeping populations of overgrazing marsh crabs in check, a new study shows. The crabs' appetite for plant roots, and their tunneling behavior had caused many of the estuary's marshes and creekbanks to erode and collapse in the otters' absence. Today, erosion has slowed by up to 90% in areas with large otter populations and marshes and streambeds are restabilizing.
Published Black summer bushfires in Australia wiped $2.8 billion from tourism supply chain
(via sciencedaily.com) Original source First input-output economic analysis of the 2019-20 Australian fires also found 7300 jobs were lost. The study highlights economic vulnerabilities to extremes of climate change.
Published Scientists pinpoint growth of brain's cerebellum as key to evolution of bird flight
(via sciencedaily.com) Original source Evolutionary biologists report they have combined PET scans of modern pigeons along with studies of dinosaur fossils to help answer an enduring question in biology: How did the brains of birds evolve to enable them to fly?
Published Geoengineering may slow Greenland ice sheet loss
(via sciencedaily.com) Original source Modeling shows that stratospheric aerosol injection has the potential to reduce ice sheet loss due to climate change.
Published New research shows how pollutants from aerosols and river run-off are changing the marine phosphorus cycle in coastal seas
(via sciencedaily.com) Original source New research sheds light on how pollutants from aerosols and river run-off are impacting coastal seas. The research identified an 'Anthropogenic Nitrogen Pump' which changes the phosphorus cycle and therefore likely coastal biodiversity and associated ecosystem services.
Published Some plastic straws degrade quicker than others
(via sciencedaily.com) Original source Not all plastics are created the same, and some last longer in the ocean than others. Scientists have been working for years to quantify the environmental lifetimes of a wide range of plastic goods to see which have the shortest and longest lifespans in the ocean. To determine what plastics persist in the ocean, the team tests different products in large tanks that recreate the natural ocean environment.
Published How did humans learn to walk? New evolutionary study offers an earful
(via sciencedaily.com) Original source A new study, which centers on evidence from skulls of a 6-million-year-old fossil ape, Lufengpithecus, offers important clues about the origins of bipedal locomotion courtesy of a novel method: analyzing its bony inner ear region using three-dimensional CT-scanning. The inner ear appears to provide a unique record of the evolutionary history of ape locomotion.
Published Rising sea levels could lead to more methane emitted from wetlands
(via sciencedaily.com) Original source A Bay Area wetlands ecosystem that was expected to serve as a carbon sink is emitting surprisingly high levels of methane, a potent greenhouse gas. The study suggests factors governing carbon cycles in these habitats are even more complex than we thought.
Published How waves and mixing drive coastal upwelling systems
(via sciencedaily.com) Original source Large coastal upwelling systems along the eastern margins of the Atlantic and Pacific Oceans are among the most biologically productive and biodiverse regions of the world's oceans. Typically, the strength and timing of upwelling in such systems are linked to the prevailing winds. Interestingly, in some tropical regions, high levels of productivity occur even when the upwelling favorable winds are weak.