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Categories: Paleontology: Climate, Space: Exploration
Published Ice sheet surface melt is accelerating in Greenland and slowing in Antarctica
(via sciencedaily.com) Original source Surface ice in Greenland has been melting at an increasing rate in recent decades, while the trend in Antarctica has moved in the opposite direction, according to researchers.
Published Over 40 percent of Antarctica's ice shelves reduced in volume over 25 years
(via sciencedaily.com) Original source 71 of the 162 ice shelves that surround Antarctica have reduced in volume over 25 years from 1997 to 2021, with a net release of 7.5 trillion tons of meltwater into the oceans, say scientists. They found that almost all the ice shelves on the western side of Antarctica experienced ice loss. In contrast, most of the ice shelves on the eastern side stayed the same or increased in volume. Over the 25 years, the scientists calculated almost 67 trillion tonnes of ice was exported to the ocean, which was offset by 59 trillion tons of ice being added to the ice shelves, giving a net loss of 7.5 trillion tons.
Published Large swings in past ocean oxygen revealed
(via sciencedaily.com) Original source As the climate warms, there is major concern that Earth's ocean will lose oxygen. A study has revealed that locked in ancient deep-sea sediments is evidence for oxygen loss in the world's ocean during past glacial periods, indicating that widespread oxygen loss with current climate change may not be permanent.
Published NASA's Webb captures an ethereal view of NGC 346
(via sciencedaily.com) Original source One of the greatest strengths of NASA's James Webb Space Telescope is its ability to give astronomers detailed views of areas where new stars are being born. The latest example, showcased here in a new image from Webb's Mid-Infrared Instrument (MIRI), is NGC 346 -- the brightest and largest star-forming region in the Small Magellanic Cloud.
Published Removal of magnetic spacecraft contamination within extraterrestrial samples easily carried out, researchers say
(via sciencedaily.com) Original source By demonstrating that spaceflight doesn’t adversely affect the magnetism of moon rocks, researchers underscore the exciting potential of studying the magnetic histories stored in these samples.
Published Researchers capture first-ever afterglow of huge planetary collision in outer space
(via sciencedaily.com) Original source A chance social media post by an eagle-eyed amateur astronomer sparked the discovery of an explosive collision between two giant planets, which crashed into each other in a distant space system 1,800 light years away from planet Earth.
Published 'Starquakes' could explain mystery signals
(via sciencedaily.com) Original source Fast radio bursts, or FRBs, are an astronomical mystery, with their exact cause and origins still unconfirmed. These intense bursts of radio energy are invisible to the human eye, but show up brightly on radio telescopes. Previous studies have noted broad similarities between the energy distribution of repeat FRBs, and that of earthquakes and solar flares. However, new research has looked at the time and energy of FRBs and found distinct differences between FRBs and solar flares, but several notable similarities between FRBs and earthquakes. This supports the theory that FRBs are caused by 'starquakes' on the surface of neutron stars. This discovery could help us better understand earthquakes, the behavior of high-density matter and aspects of nuclear physics.
Published Paleoclimatologists use ancient sediment to explore future climate in Africa
(via sciencedaily.com) Original source With global warming apparently here to stay, a team of paleoclimatologists are studying an ancient source to determine future rainfall and drought patterns: fossilized plants that lived on Earth millions of years ago.
Published Stellar fountain of youth with turbulent formation history in the center of our galaxy
(via sciencedaily.com) Original source An unexpectedly high number of young stars has been identified in the direct vicinity of a supermassive black hole and water ice has been detected at the center of our galaxy.
Published Source of electron acceleration and X-ray aurora of Mercury local chorus waves detected
(via sciencedaily.com) Original source Observations during two flybys by the Mio spacecraft as part of the BepiColombo International Mercury Exploration Project have revealed that chorus waves occur quite locally in the dawn sector of Mercury. Mercury's magnetic field is about 1% of that of Earth, and it was unclear whether chorus waves would be generated like on Earth. The present study reveals that the chorus waves are the driving source of Mercury's X-ray auroras, whose mechanism was not understood.
Published The Gulf Stream is warming and shifting closer to shore
(via sciencedaily.com) Original source The Gulf Stream is intrinsic to the global climate system, bringing warm waters from the Caribbean up the East Coast of the United States. As it flows along the coast and then across the Atlantic Ocean, this powerful ocean current influences weather patterns and storms, and it carries heat from the tropics to higher latitudes as part of the Atlantic Meridional Overturning Circulation. A new study now documents that over the past 20 years, the Gulf Stream has warmed faster than the global ocean as a whole and has shifted towards the coast. The study relies on over 25,000 temperature and salinity profiles collected between 2001 and 2023.
Published Ancient Maya reservoirs offer lessons for today's water crises
(via sciencedaily.com) Original source Ancient Maya reservoirs, which used aquatic plants to filter and clean the water, 'can serve as archetypes for natural, sustainable water systems to address future water needs.' The Maya built and maintained reservoirs that were in use for more than 1,000 years. These reservoirs provided potable water for thousands to tens of thousands of people in cities during the annual, five-month dry season and in periods of prolonged drought.
Published Deciphering the intensity of past ocean currents
(via sciencedaily.com) Original source Ocean currents determine the structure of the deep-sea ocean floor and the transport of sediments, organic carbon, nutrients and pollutants. In flume-tank experiments, researchers have simulated how currents shape the seafloor and control sediment deposition. This will help in reconstructions of past marine conditions.
Published Large mound structures on Kuiper belt object Arrokoth may have common origin
(via sciencedaily.com) Original source A new study posits that the large, approximately 5-kilometer-long mounds that dominate the appearance of the larger lobe of the pristine Kuiper Belt object Arrokoth are similar enough to suggest a common origin. The study suggests that these “building blocks” could guide further work on planetesimal formational models.
Published Study quantifies satellite brightness, challenges ground-based astronomy
(via sciencedaily.com) Original source The ability to have access to the Internet or use a mobile phone anywhere in the world is taken more and more for granted, but the brightness of Internet and telecommunications satellites that enable global communications networks could pose problems for ground-based astronomy. Scientists confirm that recently deployed satellites are as bright as stars seen by the unaided eye.
Published Bursts of star formation explain mysterious brightness at cosmic dawn
(via sciencedaily.com) Original source In the James Webb Space Telescope’s (JWST) first images of the universe’s earliest galaxies, the young galaxies appear too bright, too massive and too mature to have formed so soon after the Big Bang. Using new simulations, a team of astrophysicists now has discovered that these galaxies likely are not so massive after all. Although a galaxy’s brightness is typically determined by its mass, the new findings suggest that less massive galaxies can glow just as brightly from irregular, brilliant bursts of star formation.
Published Scientists investigate Grand Canyon's ancient past to predict future climate impacts
(via sciencedaily.com) Original source A team explores relationship between warming post-Ice Age temperatures and intensifying summer monsoon rains on groundwater reserves.
Published Climate and human land use both play roles in Pacific island wildfires past and present
(via sciencedaily.com) Original source It’s long been understood that human settlement contributes to conditions that make Pacific Islands more susceptible to wildfires, such as the devastating Aug. 8 event that destroyed the Maui community of Lahaina. But a new study from fire scientist shows that climate is an undervalued part of the equation.
Published Ancient plant wax reveals how global warming affects methane in Arctic lakes
(via sciencedaily.com) Original source In a new study, researchers examined the waxy coatings of leaves preserved as organic molecules within sediment from the early-to-middle Holocene, a period of intense warming that occurred due to slow changes in Earth's orbit 11,700 to 4,200 years ago. They found that warming potentially could lead to a previously under-appreciated flux in methane emissions from lakes.
Published New study removes human bias from debate over dinosaurs' demise
(via sciencedaily.com) Original source Researchers tried a new approach to resolve the scientific debate over whether it was a giant asteroid or volcanoes that wiped out the dinosaurs -- they removed scientists from the debate and let the computers decide. The researchers created a model powered by 130 interconnected processors that, without human input, reverse-engineered the Cretaceous-Paleogene mass extinction until they reached a scenario that matched the fossil record. The model determined that while a meteorite contributed to the cataclysm, the outpouring of climate-altering gases from the nearly 1-million-year eruptions of volcanoes in western India's Deccan Traps would have been sufficient to trigger the extinction and clear the way for the ascendance of mammals.