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Categories: Offbeat: Space, Paleontology: Climate
Published The Moon is 40 million years older than previously thought
(via sciencedaily.com) Original source By analyzing tiny lunar crystals gathered by Apollo 17 astronauts in 1972, researchers recalculated the age of the Earth's Moon. Although previous assessments estimated the Moon as 4.425 billion years old, the new study discovered it is actually 4.46 billion years old -- 40 million years older than previously thought.
Published Astronomers detect most distant fast radio burst to date
(via sciencedaily.com) Original source An international team has spotted a remote blast of cosmic radio waves lasting less than a millisecond. This 'fast radio burst' (FRB) is the most distant ever detected. Its source was pinned down by the European Southern Observatory's (ESO) Very Large Telescope (VLT) in a galaxy so far away that its light took eight billion years to reach us. The FRB is also one of the most energetic ever observed; in a tiny fraction of a second it released the equivalent of our Sun's total emission over 30 years.
Published New study finds 50-year trend in hurricane escalation linked to climate change
(via sciencedaily.com) Original source New research by climate scientists indicates that there have been great changes to Atlantic hurricanes in just the past 50 years, with storms developing and strengthening faster.
Published Subalpine forests in the Northern Rockies are fire resilient--for now
(via sciencedaily.com) Original source Using lake sediment cores, scientists determined how these subalpine ecosystems recovered after 4,800 years of fire.
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 '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 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 Scientists discover the highest energy gamma-rays ever from a pulsar
(via sciencedaily.com) Original source Scientists have detected the highest energy gamma rays ever from a dead star called a pulsar. The energy of these gamma rays clocked in at 20 tera-electronvolts, or about ten trillion times the energy of visible light. This observation is hard to reconcile with the theory of the production of such pulsed gamma rays, as the international team reports.
Published Plot thickens in hunt for ninth planet
(via sciencedaily.com) Original source A pair of theoretical physicists are reporting that the same observations inspiring the hunt for a ninth planet might instead be evidence within the solar system of a modified law of gravity originally developed to understand the rotation of galaxies.
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.