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Categories: Geoscience: Oceanography, Physics: Acoustics and Ultrasound

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Climate changes usually happens over long periods of time, but during the last glacial period, extreme fluctuations in temperature occurred within just a few years. Researchers have now been able to prove the phenomenon also occurred during the penultimate glacial period.

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Researchers have uncovered the first direct evidence that the West Antarctic Ice Sheet shrunk suddenly and dramatically at the end of the Last Ice Age, around eight thousand years ago. The evidence, contained within an ice core, shows that in one location the ice sheet thinned by 450 meters -- that's more than the height of the Empire State Building -- in just under 200 years.

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Inspired during field work in South Australia's Flinders Ranges, geoscientists have proposed that all-time low volcanic carbon dioxide emissions triggered a 57-million-year-long global 'Sturtian' ice age.

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New research reveals that denser, and more sheltered, kelp forests can withstand serious stressors amid warming ocean temperatures.

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New research sheds light on tiny plankton, which measure less than 0.02mm in diameter but can make up more than 70% of the plankton biomass found in the ocean.

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The Circumpolar Current works as a regulator of the planet's climate. Its origins were thought to have caused the formation of the permanent ice in Antarctica about 34 million years ago. Now, a study has cast doubt on this theory, and has changed the understanding of how the ice sheet in Antarctic developed in the past, and what this could mean in the future as the planet's climate changes.

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Scientists have found soundwaves from low-intensity focused ultrasound aimed at a place deep in the brain called the insula can reduce both the perception of pain and other effects of pain, such as heart rate changes.

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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.

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Researchers demonstrated a 300 GHz-band wireless link that was able to transmit data over a single channel at a rate of 240 gigabits per second. The wireless communication system employs signal generators based on lasers that have ultra-low phase noise in the sub-terahertz band. This rate is the highest so far reported at these frequencies and is a substantial step forward in 300 GHz-band communications for 6G networks.

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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.

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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.

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New research examines the causes of the record-breaking ocean temperatures witnessed in 2023.

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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.

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Modeling shows that stratospheric aerosol injection has the potential to reduce ice sheet loss due to climate change.

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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.

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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.

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Researchers are developing a new type of sensor that reacts to certain sound waves, causing it to vibrate. The sensor is a metamaterial that acquires its special properties through the structuring of the material. Passive sound-sensitive sensors could be used to monitor buildings, earthquakes or certain medical devices and save millions of batteries.

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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.

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Instead of tubular commercial aircraft, other designs could be used in the future: Jets with a blended wing body would fly more efficiently and make less noise -- but how would the noise emissions from these new types of aircraft affect people?

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Hydrothermal vents and manganese nodule fields in the deep oceans contain more biodiversity than expected.