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Micro- and nanoplastic from the atmosphere is polluting the ocean
According to estimates, by 2040 the level of plastic pollution could reach 80 million metric tons per year. Plastic particles have now been detected in virtually all spheres of the environment, e.g. in water bodies, the soil and the air. Via ocean currents and rivers, the tiny plastic particles can even reach the Arctic, Antarctic or ocean depths. A new overview study has now shown that wind, too, can transport these particles great distances -- and much faster than water can: in the atmosphere, they can travel from their point of origin to the most remote corners of the planet in a matter of days.
More difficult than expected for glaciers to recover from climate warming
Ice shelves are floating extensions of glaciers. If Greenland's second largest ice shelf breaks up, it may not recover unless Earth's future climate cools considerably.
Newly discovered lake may hold secret to Antarctic ice sheet's rise and fall
Scientists investigating the underside of the world's largest ice sheet in East Antarctica have discovered a city-size lake whose sediments might answer questions about what Antarctica was like before it froze, how climate change has affected it over its history, and how the ice sheet might behave as the world warms.
Ice-capped volcanoes slower to erupt, study finds
The Westdahl Peak volcano in Alaska last erupted in 1992, and continued expansion hints at another eruption soon. Experts previously forecasted the next blast to occur by 2010, but the volcano -- located under about 1 kilometer of glacial ice -- has yet to erupt again. Using the Westdahl Peak volcano as inspiration, a new volcanic modeling study examined how glaciers affect the stability and short-term eruption cycles of high-latitude volcanic systems -- some of which exist along major air transportation routes.
In sediments below Antarctic ice, scientists discover a giant groundwater system
A team has mapped a huge, actively circulating groundwater system in deep sediments in West Antarctica. They say such systems, probably common in Antarctica, may have as-yet unknown implications for how the frozen continent reacts to, or possibly even contributes to, climate change.
Landslides can have a major impact on glacier melt and movement
Using satellite imagery to study the effects of a 2019 landslide on the Amalia Glacier in Patagonia, a research team found the landslide helped stabilize the glacier and caused it to grow by about 1,000 meters over the last three years.
Precipitation helped drive distribution of Alaska dinosaurs
Precipitation more than temperature influenced the distribution of herbivorous dinosaurs in what is now Alaska, according to new research. The finding discusses the distribution of hadrosaurids and ceratopsids -- the megaherbivores of the Late Cretaceous Period, 100.5 million to 66 million years ago.
Carbon, climate change and ocean anoxia in an ancient icehouse world
A new study describes a period of rapid global climate change in an ice-capped world much like the present -- but 304 million years ago. Within about 300,000 years, atmospheric carbon dioxide levels doubled, oceans became anoxic, and biodiversity dropped on land and at sea.
Researchers home in on Thera volcano eruption date
Tree-ring, ice core and volcano experts teamed up to identify one of the most climatically impactful volcanic eruptions in 4,000 years -- Aniakchak II. In the process, they narrowed down potential dates for the Thera volcano eruption.
Study supports stronger conservation efforts Appalachians and the Gulf Coast, US
Study of Campanula americana supports strengthening conservation efforts in glacial refugia areas because of their high genetic diversity. Conservation of those areas in the southern Appalachians and the Gulf Coast has implications for other areas of the country.
Model pinpoints glaciers at risk of collapse due to climate change
Glaciologists focus on what happens at the front of glaciers that terminate in the ocean as the key to whether a glacier will speed up or slow down. Yet with global warming, meltwater is becoming increasingly important, seeping underneath and lubricating flow. A statistician included this effect in glacier flow models, concluding that the thickest and fastest moving glaciers will respond most rapidly to basal lubrication and are most vulnerable to sudden collapse.
Earth's atmosphere may be source of some lunar water
Hydrogen and oxygen ions escaping from Earth's upper atmosphere and combining on the moon could be one of the sources of the known lunar water and ice, according to new research.
Before Stonehenge monuments, hunter-gatherers made use of open habitats
Hunter-gatherers made use of open woodland conditions in the millennia before Stonehenge monuments were built, according to a new study.
News from the climate history of the Dead Sea
The lake level of the Dead Sea is currently dropping by more than one meter every year -- mainly because of the heavy water consumption in the catchment area. However, very strong lake level drops due to climate changes are also known from earlier times. At the end of the last ice age, for example, the water level dropped by almost 250 meters within a few millennia.
Deepest sediment core collected in the Atlantic Ocean
A team of scientists, engineers, and ship's crew on the research vessel Neil Armstrong operated by the Woods Hole Oceanographic Institution (WHOI) recently collected a 38-foot-long cylindrical sediment sample from the deepest part of the Puerto Rico Trench, nearly 5 miles below the surface.
Melting land-based ice raises sea levels globally but can produce lowered levels locally
When a large ice sheet begins to melt, global-mean sea level rises, but local sea level near the ice sheet may in fact drop. A researcher illustrates this effect through a series of calculations, beginning with a simple, analytically tractable model and progressing through more sophisticated mathematical estimations of ice distributions and gravitation of displaced seawater mass. The paper includes numerical results for sea level change resulting from a 1,000-gigatonne loss of ice, with parameter values appropriate to the Greenland and Antarctic ice sheets.
Study challenges theories of earlier human arrival in Americas
The new analysis suggests that misinterpretation of archaeological evidence at certain sites in North and South America might be responsible for theories that humans arrived long before 13,000-14,200 years ago.
Explanation for formation of abundant features on Europa bodes well for search for extraterrestrial life
Ice-penetrating radar data from Greenland suggests that shallow water pockets may be common within Europa's ice shell, increasing the potential habitability of the Jovian moon's ice shell.
No glacial fertilization effect in the Antarctic Ocean
Can iron-rich dust fertilize the ocean, stimulate algae growth there, and thereby capture carbon dioxide from the atmosphere? An international research team used deep-sea sediment cores from the Scotia Sea to investigate whether this hypothetical greenhouse gas sink had an effect during ice ages. Although dust input was high during ice ages, no evidence of a fertilization effect could be found in the Antarctic Ocean. Rather, the production of algae, for example, and thus carbon dioxide sequestration, was high only during warm periods when dust input was low.
Changes in vegetation shaped global temperatures over last 10,000 years
Follow the pollen. Records from past plant life tell the real story of global temperatures. Warmer temperatures brought plants -- and then came even warmer temperatures, according to new model simulations.
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