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Categories: Archaeology: General, Geoscience: Earth Science
Published Ecosystem evolution in Africa



New research pushes back the oldest evidence of C4 grass-dominated habitats in Africa -- and globally -- by more than 10 million years, with important implications for primate evolution and the origins of tropical C4 grasslands and savanna ecosystems across the African continent and around the world.
Published The future is foggy for Arctic shipping



As the Arctic warms and loses sea ice, trans-Arctic shipping has increased, reducing travel time and costs for international trade. However, a new study finds that the Arctic Ocean is getting foggier as ice disappears, reducing visibility and causing costly delays as ships slow to avoid hitting dangerous sea ice.
Published Is the ocean a solution for ushering in the era of environmentally friendly energy?



Researchers confirm the superiority of seawater batteries that use chelating agents.
Published Twilight zone at risk from climate change



Life in the ocean's 'twilight zone' could decline dramatically due to climate change, new research suggests.
Published Prolonged droughts likely spelled the end for Indus megacities



New research has found evidence -- locked into an ancient stalagmite from a cave in the Himalayas -- of a series of severe and lengthy droughts which may have upturned the Bronze Age Indus Civilization.
Published Ocean ecosystem: Mixotrophic microorganisms play key role



Researchers have identified a previously unknown group of bacteria, called UBA868, as key players in the energy cycle of the deep ocean. They are significantly involved in the biogeochemical cycle in the marine layer between 200 and 1000 meters.
Published Searching for ancient bears in an Alaskan cave led to an important human discovery



Genetic analysis links 3,000-year-old bone found in cave to modern Alaska Natives.
Published Massive iceberg discharges during the last ice age had no impact on nearby Greenland, raising new questions about climate dynamics



New findings suggest that Heinrich Events had no discernible impact on temperatures in Greenland, which could have repercussions for scientists' understanding of past climate dynamics.
Published A more precise model of the Earth's ionosphere



The ionosphere -- the region of geospace spanning from 60 to 1000 kilometers above the Earth -- impairs the propagation of radio signals from global navigation satellite systems (GNSS) with its electrically charged particles. This is a problem for the ever higher precision required by these systems -- both in research and for applications such as autonomous driving or precise orbit determination of satellites. Models of the ionosphere and its uneven, dynamic charge distribution can help correct the signals for ionospheric delays, which are one of the main error sources in GNSS applications. Researchers have presented a new model of the ionosphere, developed on the basis of neural networks and satellite measurement data from 19 years. In particular, it can reconstruct the topside ionosphere, the upper, electron-rich part of the ionosphere much more precisely than before. It is thus also an important basis for progress in ionospheric research, with applications in studies on the propagation of electromagnetic waves or for the analysis of certain space weather events, for example.
Published Algae in Swedish lakes provide insights to how complex life on Earth developed



By studying green algae in Swedish lakes, a research team has succeeded in identifying which environmental conditions promote multicellularity. The results give us new clues to the amazing paths of evolution.
Published Arctic ice algae heavily contaminated with microplastics



The alga Melosira arctica, which grows under Arctic sea ice, contains ten times as many microplastic particles as the surrounding seawater. This concentration at the base of the food web poses a threat to creatures that feed on the algae at the sea surface. Clumps of dead algae also transport the plastic with its pollutants particularly quickly into the deep sea -- and can thus explain the high microplastic concentrations in the sediment there.
Published Ridgecrest faults increasingly sensitive to solid Earth tides before earthquakes



Faults in the Ridgecrest, California area were very sensitive to solid earth tidal stresses in the year and a half before the July 2019 Ridgecrest earthquake sequence.
Published The climate crisis and biodiversity crisis can't be approached as two separate things



Anthropogenic climate change has, together with the intensive use and destruction of natural ecosystems through agriculture, fishing and industry, sparked an unprecedented loss of biodiversity that continues to worsen. In this regard, the climate crisis and biodiversity crisis are often viewed as two separate catastrophes. An international team of researchers calls for adopting a new perspective.
Published Using solar farms to generate fresh desert soil crust



Biocrusts play a crucial role in maintaining soil health and ecosystem sustainability, but they are currently under assault. Human activities including agriculture, urbanization, and off-road vehicle use can lead to the degradation of biocrusts, which have long-term consequences for these fragile environments. Climate change is also placing stress on biocrusts, which struggle to adapt to sunlight and searing heat in arid landscapes like the Sonoran Desert.
Published Turkey's next quake: Research shows where, how bad -- but not 'when'



Using remote sensing, geophysicists have documented the massive Feb. 6 quake that killed more than 50,000 people in Eastern Turkey and toppled more than 100,000 buildings. Alarmingly, researchers found that a section of the fault remains unbroken and locked -- a sign that the plates there may, when friction intensifies, generate another magnitude 6.8 earthquake when it finally gives way.
Published Water arsenic including in public water is linked to higher urinary arsenic totals among the U.S. population



A new study shows that water arsenic levels are linked to higher urinary arsenic among the U.S. population for users of both private wells and public water systems.
Published New USGS-FEMA report updates economic risk from earthquakes



Even though most of the economic losses are concentrated in California and along the West Coast due to that region's high seismic hazard levels, significant population, and building exposure, earthquake risk is spread throughout the country. For example, there is a combined $3.1 billion per year in projected losses across the central U.S., Rocky Mountain region, Alaska, Hawaii, Puerto Rico and the Virgin Islands.
Published Research collaboration aims to improve nationwide water quality, restore wetlands



The new classification system demonstrates the effects wetlands have on water quality at a continental scale -- invaluable data that can be used to better define whether wetlands are federally regulated under the U.S. Clean Water Act.
Published Polar ice sheet melting records have toppled during the past decade



The seven worst years for polar ice sheets melting and losing ice have occurred during the past decade, according to new research, with 2019 being the worst year on record. The seven worst years for polar ice sheets melting and losing ice have occurred during the past decade, according to new research, with 2019 being the worst year on record. The melting ice sheets now account for a quarter of all sea level rise -- a fivefold increase since the 1990's -- according to researchers who have combined 50 satellite surveys of Antarctica and Greenland taken between 1992 and 2020, funded by NASA and the European Space Agency.
Published Immediate carbon cuts, common marine heatwave terminology urged



Oceanographers provide a reality check on the limitations of carbon dioxide removal and a warning that marine heatwaves need clear definitions so communities can adapt.