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Categories: Geoscience: Geology, Paleontology: Climate
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 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 Unexpected biodiversity on the ocean floor
(via sciencedaily.com) Original source Hydrothermal vents and manganese nodule fields in the deep oceans contain more biodiversity than expected.
Published Ancient brown bear genomes sheds light on Ice Age losses and survival
(via sciencedaily.com) Original source The brown bear is one of the largest living terrestrial carnivores, and is widely distributed across the Northern Hemisphere. Unlike many other large carnivores that went extinct at the end of the last Ice Age (cave bear, sabretoothed cats, cave hyena), the brown bear is one of the lucky survivors that made it through to the present. The question has puzzled biologists for close to a century -- how was this so?
Published New tool predicts flood risk from hurricanes in a warming climate
(via sciencedaily.com) Original source A new method predicts how much flooding a coastal community is likely to experience as hurricanes evolve due to climate change. Using New York as a test case, the model predicts Hurricane Sandy-level flooding will occur roughly every 30 years by 2099.
Published Records of cometary dust hitting the asteroid Ryugu
(via sciencedaily.com) Original source The Hayabusa2 mission that collected samples from the asteroid Ryugu has provided a treasure trove of insights into our solar system. After analyzing samples further, a team of researchers have unearthed evidence that cometary organic matter was transported from space to the near-Earth region.
Published Planetary Commons: Fostering global cooperation to safeguard critical Earth system functions
(via sciencedaily.com) Original source Tipping elements of the Earth system should be considered global commons, researchers argue. Global commons cannot -- as they currently do -- only include the parts of the planet outside of national borders, like the high seas or Antarctica. They must also include all the environmental systems that regulate the functioning and state of the planet, namely all systems on Earth we all depend on, irrespective on where in the world we live. This calls for a new level of transnational cooperation, leading experts in legal, social and Earth system sciences say. To limit risks for human societies and secure critical Earth system functions they propose a new framework of planetary commons to guide governance of the planet.
Published Ice age could help predict oceans' response to global warming
(via sciencedaily.com) Original source A new way to measure the ocean oxygen level and its connections with carbon dioxide in the Earth's atmosphere during the last ice age could help explain the role oceans played in past glacial melting cycles and improve predictions of how ocean carbon cycles will respond to global warming.
Published Why animals shrink over time explained with new evolution theory
(via sciencedaily.com) Original source The new theoretical research proposes that animal size over time depends on two key ecological factors.
Published Key factors in human-made earthquakes
(via sciencedaily.com) Original source Researchers report that the roughness of pre-existing faults and associated stress heterogeneity in geological reservoirs play a key role for causing human-made earthquakes, so-called runaway events. The study combines novel fluid injection experiments under acoustic monitoring performed in GFZ's geomechanical laboratory with numerical modelling results.
Published The heat is on: Scientists discover southern Africa's temps will rise past the rhinos' tolerance
(via sciencedaily.com) Original source Southern Africa contains the vast majority of the world's remaining populations of both black and white rhinoceroses (80% and 92%, respectively). The region's climate is changing rapidly as a result global warming. Traditional conservation efforts aimed at protecting rhinos have focused on poaching, but until now, there has been no analysis of the impact that climate change may have on the animals. A research team has recently reported that, though the area will be affected by both higher temperatures and changing precipitation, the rhinos are more sensitive to rising temperatures, which will quickly increase above the animals' acceptable maximum threshold.
Published Stalagmites as climate archive
(via sciencedaily.com) Original source When combined with data from tree-ring records, stalagmites can open up a unique archive to study natural climate fluctuations, a research team has demonstrated. The researchers analyzed the isotopic composition of oxygen in a stalagmite formed from calcareous water in a cave in southern Germany. In conjunction with the data acquired from tree rings, they were able to reconstruct short-term climate fluctuations over centuries and correlate them with historically documented environmental events.
Published Key moment in the evolution of life on Earth captured in fossils
(via sciencedaily.com) Original source New research has precisely dated some of the oldest fossils of complex multicellular life in the world, helping to track a pivotal moment in the history of Earth when the seas began teeming with new lifeforms -- after four billion years of containing only single-celled microbes.
Published Study uncovers potential origins of life in ancient hot springs
(via sciencedaily.com) Original source A research team investigated how the emergence of the first living systems from inert geological materials happened on the Earth, more than 3.5 billion years ago. Scientists found that by mixing hydrogen, bicarbonate, and iron-rich magnetite under conditions mimicking relatively mild hydrothermal vent results in the formation of a spectrum of organic molecules, most notably including fatty acids stretching up to 18 carbon atoms in length.
Published The first assessment of toxic heavy metal pollution in the Southern Hemisphere over the last 2,000 years
(via sciencedaily.com) Original source Human activity, from burning fossil fuels and fireplaces to the contaminated dust produced by mining, alters Earth's atmosphere in countless ways. Records of these impacts over time are preserved in everlasting polar ice that serves as a sort of time capsule, allowing scientists and historians to link Earth's history with that of human societies. In a new study, ice cores from Antartica show that lead and other toxic heavy metals linked to mining activities polluted the Southern Hemisphere as early as the 13th century.
Published Ancient cities provide key datasets for urban planning, policy and predictions in the Anthropocene
(via sciencedaily.com) Original source A new study shows how state-of-the-art methods and perspectives from archaeology, history, and palaeoecology are shedding new light on 5,500 years of urban life.
Published Meteorite analysis shows Earth's building blocks contained water
(via sciencedaily.com) Original source Analysis of iron meteorites from the earliest years of the solar system indicate that the planetary 'seeds' that ultimately formed Earth contained water.
Published From NYC to DC and beyond, cities on the East Coast are sinking
(via sciencedaily.com) Original source Major cities on the U.S. Atlantic coast are sinking, in some cases as much as 5 millimeters per year -- a decline at the ocean's edge that well outpaces global sea level rise, confirms new research. Particularly hard hit population centers such as New York City and Long Island, Baltimore, and Virginia Beach and Norfolk are seeing areas of rapid 'subsidence,' or sinking land, alongside more slowly sinking or relatively stable ground, increasing the risk to roadways, runways, building foundations, rail lines, and pipelines, according to a new study.
Published Mysterious fruit shown to be the oldest known fossils of the Frankincense and Myrrh family
(via sciencedaily.com) Original source Early in the 1970s, paleontologists discovered strange fossilized fruits between hardened rock from one of the largest volcanic eruptions in Earth's history. The identity of these fossils remained elusive for the next several decades. Using CT scanning, scientists have now determined they are the oldest fossils from species in the Frankincense and Myrrh family.
Published Mesopotamian bricks unveil the strength of Earth's ancient magnetic field
(via sciencedaily.com) Original source Ancient bricks inscribed with the names of Mesopotamian kings have yielded important insights into a mysterious anomaly in Earth's magnetic field 3,000 years ago, according to a new study.