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Categories: Paleontology: Climate, Space: Astrophysics

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A temperature reconstruction from ice cores of the past 1,000 years reveals that today's warming in central-north Greenland is surprisingly pronounced. The most recent decade surveyed in a study, the years 2001 to 2011, was the warmest in the past 1,000 years, and the region is now 1.5 °C warmer than during the 20th century, as researchers report. Using a set of ice cores unprecedented in length and quality, they reconstructed past temperatures in central-north Greenland and melting rates of the ice sheet.

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Recent research shows that magnetic fields can spontaneously emerge in a plasma if the plasma has a temperature anisotropy. This mechanism is known as the Weibel instability. This new research is the first to unambiguously observe the Weibel instability in the laboratory. It offers a possible solution to the problem of the origin of the microgauss-level magnetic fields that permeate the galaxies.

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Hundreds of millions of light-years away in a distant galaxy, a star orbiting a supermassive black hole is being violently ripped apart under the black hole's immense gravitational pull. As the star is shredded, its remnants are transformed into a stream of debris that rains back down onto the black hole to form a very hot, very bright disk of material swirling around the black hole, called an accretion disc. This phenomenon -- where a star is destroyed by a supermassive black hole and fuels a luminous accretion flare -- is known as a tidal disruption event (TDE), and it is predicted that TDEs occur roughly once every 10,000 to 100,000 years in a given galaxy.

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Understanding how dust grains form in interstellar gas could offer significant insights to astronomers and help materials scientists develop useful nanoparticles.

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A team has studied the relation between galaxy size and luminosity of some of the earliest galaxies in the universe taken by the James Webb Space Telescope, less than a billion years after the Big Bang.

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Black holes are gatherers, not hunters. They lie in wait until a hapless star wanders by. When the star gets close enough, the black hole's gravitational grasp violently rips it apart and sloppily devours its gasses while belching out intense radiation. Astronomers have recorded a star's final moments in detail as it gets gobbled up by a black hole.

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A new theory could explain the origin and properties of systems of rocky super-Earths and their relationship with the terrestrial planets of the solar system.

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Something is amiss in the Butterfly Nebula. When astronomers compared two exposures of this planetary nebula that had been taken by the Hubble Space Telescope in 2009 and 2020, they saw dramatic changes in the material within its 'wings.' Powerful winds are apparently driving complex alterations of material within the Butterfly Nebula, behavior not seen in planetary nebulae to date. The researchers want to understand how such activity is possible from what should be a 'sputtering, largely moribund star with no remaining fuel.'

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An international team of collaborators have revealed the most detailed look yet at the planet's recent climactic history, including summer and winter temperatures dating back 11,000 years to the beginning of what is known as the Holocene.

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Hispaniola once had among the highest diversity of rodents in the Caribbean. Today, only one rodent species remains, and its prospects for survival are uncertain. New carbon dates place the blame squarely on humans.

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Climate change will slow down deep overturning ocean circulation in the coming centuries. Using three dozen Earth system models, researchers have concluded that the Southern Meridional Overturning Circulation could completely shut down by 2300, causing disaster to the marine ecosystem on a large portion of the planet.

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A new study that reconstructs the history of sea level at the Bering Strait shows that the Bering Land Bridge connecting Asia to North America did not emerge until around 35,700 years ago, less than 10,000 years before the height of the last ice age (known as the Last Glacial Maximum). The findings indicate that the growth of the ice sheets -- and the resulting drop in sea level -- occurred surprisingly quickly and much later in the glacial cycle than previous studies had suggested.

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Scientists have discovered that the atmosphere contained far less CO2 than previously thought when forests emerged on our planet, the new study has important implications for understanding how land plants affect the climate.

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Spread across vast distances, the islands of the tropical Pacific Ocean are thought to have been populated by humans in two distinct migrations beginning approximately 3,330 years ago. The first followed a northern route out of what is today the Philippines and the second followed a southern route from Taiwan and New Guinea. People arrived on the islands between these routes -- now making up the Federated States of Micronesia -- about 1,000 years later. But a new finding by sea-level researchers suggests that the islands in Micronesia were possibly settled much earlier than supposed and that voyagers on the two routes may have interacted with one another.

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Fossilized microbial skins can give us a glimpse of how the climate was in the deep geological past. By discovering the 'missing link' between such fossil skins and the skins of living bacteria, researchers have greatly improved the accuracy of climate reconstructions and predictions.

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Climate change, rather than competition, played a key role in the ascendancy of dinosaurs through the Late Triassic and Early Jurassic periods.

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Sediment cores obtained from Eifel maar sites provide insight into the presence of large Ice Age mammals in Central Europe over the past 60,000 years: Overkill hypothesis not confirmed. Herds of megafauna, such as mammoth and bison, have roamed the prehistoric plains in what is today's Central Europe for several tens of thousands of years. As woodland expanded at the end of the last Ice Age, the numbers of these animals declined and by roughly 11,000 years ago, they had completely vanished from this region. Thus, the growth of forests was the main factor that determined the extinction of such megafauna in Central Europe.

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Changes in Earth's orbit that favored hotter conditions may have helped trigger a rapid global warming event 56 million years ago. Researchers found the shape of Earth's orbit, or eccentricity, and the wobble in its rotation, or precession, favored hotter conditions at the onset of the PETM and that these orbital configurations together may have played a role in triggering the event.

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By assessing so-called 'flavors' of El Nino events in past climate records and model simulations, researchers have a clearer picture of El Nino patterns over the past 12,000 years and are able to more accurately project future changes and impacts of this powerful force.

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Researchers have been studying the effects of the sudden decrease in global temperatures that occurred about 8,200 years ago, the so-called 8.2-kiloyear event, with the help of mineral deposits present in White Moon Cave in Northern California. New indications show that oscillations between extreme wetness and aridity in California were closely linked with the occurrence of wildfires. The researchers have concluded that such events are likely to become more common in the face of human-induced climate change.