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Categories: Geoscience: Geomagnetic Storms, Paleontology: Climate

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New research has uncovered a possible clue as to why glaciers that terminate at the sea are retreating at unprecedented rates: the bursting of tiny, pressurized bubbles in underwater ice.

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Antarctica's vast ice masses seem far away, yet they store enough water to raise global sea levels by several meters. A team of experts has now provided the first systematic stability inspection of the ice sheet's current state. Their diagnosis: While they found no indication of irreversible, self-reinforcing retreat of the ice sheet in West Antarctica yet, global warming to date could already be enough to trigger the slow but certain loss of ice over the next hundreds to thousands of years.

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Radiocarbon dating on bones in the La Brea Tar Pits lead archaeologists to warn that history may be repeating itself.

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Recent paleogenomic research revealed that interbreeding was common among early human species. However, little was known about when, where, and how often this hominin interbreeding took place. Using paleoanthropological evidence, genetic data, and supercomputer simulations of past climate, a team of international researchers has found that interglacial climates and corresponding shifts in vegetation created common habitats for Neanderthals and Denisovans, increasing their chances for interbreeding and gene flow in parts of Europe and central Asia.

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A new study shows that the cheek teeth of proboscideans (elephants and their ancient relatives) evolved in response to dietary changes due to vegetation changes and climate change in East Africa during the last 26 million years.

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A new study finds that past changes in atmospheric CO2 and corresponding shifts in climate and vegetation played a key role in determining when and where early human species interbred.

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A new study finds that around 1.12 million years ago a massive cooling event in the North Atlantic and corresponding shifts in climate, vegetation and food resources disrupted early human occupation of Europe.

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New research links chemical changes in seawater to volcanic activity and changes.

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If climate models predict that much of tropical Africa will become wetter with a warming climate, then why does it keep getting drier in the Horn of Africa?

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Geophysicists studied the activity of high energy electrons and clarified the unexpected protective role of the geomagnetic field surrounding the Earth.

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A subpolar species associated with Atlantic water expanded far into the Arctic Ocean during the Last Interglacial, analysis of microfossil content of sediment cores reveals. This implies that summers in the Arctic were ice free during this period.

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An international drilling expedition off the Norwegian coast confirms the theory that methane emissions from hydrothermal vents were responsible for global warming about 55 million years ago. The study shows that the vents were active in very shallow water depth or even above sea level, which would have allowed much larger amounts of methane to enter the atmosphere.

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A chemical process used in the browning of food to give it its distinct smell and taste is probably happening deep in the oceans, where it helped create the conditions necessary for life. Known as the Maillard reaction after the French scientist who discovered it, the process converts small molecules of organic carbon into bigger molecules known as polymers. In the kitchen, it is used to create flavors and aromas out of sugars. But a research team argues that on the sea floor, the process has had a more fundamental effect, where it has helped to raise oxygen and reduce carbon dioxide levels in the atmosphere, to create the conditions for complex life forms to emerge and thrive on Earth.

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A patch of ocean in the North Atlantic is stubbornly cooling while much of the planet warms. This anomaly -- dubbed the 'cold blob' -- has been linked to changes in ocean circulation, but a new study found changes in large-scale atmospheric patterns may play an equally important role, according to an international research team.

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Earth is rapidly warming and scientists are developing a variety of approaches to reduce the effects of climate change. An astronomer has proposed a novel approach -- a solar shield to reduce the amount of sunlight hitting Earth, combined with a tethered, captured asteroid as a counterweight. Engineering studies using this approach could start now to create a workable design that could mitigate climate change within decades.

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In past ice ages, the intensity of summer insolation affected the emergence of warm and cold periods and played an important role in triggering abrupt climate changes, a study by climate researchers, geoscientists, and environmental physicists suggests. Using stalagmites in the European Alps, they were able to demonstrate that warm phases appeared primarily when the summer insolation reached maxima in the Northern Hemisphere.

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A large portion of Greenland was an ice-free tundra landscape -- perhaps covered by trees and roaming woolly mammoths -- in the recent geologic past (about 416,000 years ago), a new study shows. The results help overturn a previous view that much of the Greenland ice sheet persisted for most of the last two and a half million years. Instead, moderate warming, from 424,000 to 374,000 years ago, led to dramatic melting. At that time, the melting of Greenland caused at least five feet of sea level rise, despite atmospheric levels of heat-trapping carbon dioxide being far lower than today (280 vs. 420 ppm). This indicates that the ice sheet on Greenland may be more sensitive to human-caused climate change than previously understood -- and will be vulnerable to irreversible, rapid melting in coming centuries.

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An international team of researchers has chosen the location which best represents the beginnings of what could be a new geological epoch, the Anthropocene. The Anthropocene Working Group have put forward Crawford Lake, in Canada, as a Global Boundary Stratotype Section and Point (GSSP) for the Anthropocene. A GSSP is an internationally agreed-upon reference point to show the start of a new geological period or epoch in layers of rock that have built up through the ages.

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Research shows global cooling of the climate 10 million years ago led to an explosion of diversity in terrestrial orchids.

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Researchers are using a new model to clarify why millions of years ago more animal species from Asia made the leap to the Australian continent than vice versa. The climate in which the species evolved played an important role.