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Categories: Geoscience: Geochemistry, Paleontology: Climate

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Using synchrotron techniques, scientists have unveiled important information on The Great Oxidation Event by studying apatite inclusions in zircon crystals from old magmas.

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A recent study finds that Arctic soil methane uptake may be larger than previously thought, and that methane uptake increases under dry conditions and with availability of labile carbon substrates.

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In the atmosphere, gaseous sulfuric acid can form particles that influence the physical properties of clouds. Thus, the formation of sulfuric acid in the gas phase directly affects the radiative forcing and Earth's climate. In addition to the known formation from sulfur dioxide, researchers have now been able to demonstrate through experiments that there is another formation pathway that has been speculated about for decades. Sulfuric acid in the atmosphere can also be formed directly by the oxidation of organic sulfur compounds. This new production pathway can be responsible for up to half of the gaseous sulfuric acid formation over the oceans and is thus of high importance for climate projections -- especially over the oceans of the Southern Hemisphere.

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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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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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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.

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As the Arctic warms, shrinking glaciers are exposing bubbling groundwater springs which could provide an underestimated source of the potent greenhouse gas methane, finds new research.