According to a recent study, severe and long-lasting river droughts, lasting over 85 years each, impacted the Indus basin from 4,400 to 3,400 years ago. This finding may provide insights into the gradual decline of this ancient civilization and underscores how environmental factors can influence historical societies.
An artist’s reconstruction of the gates and drainage channels of the ancient city of Harappa. Image credit: Chris Sloan.
The Indus Valley Civilization, one of the earliest urban cultures, thrived between 5,000 and 3,500 years ago along the Indus River and its tributaries in present-day Pakistan and northwestern India.
During its zenith, around 4,500 to 3,900 years ago, the civilization was noted for its advanced urban centers and sophisticated systems for managing water resources.
Despite this, the reasons behind the protracted decline following its peak remain largely elusive.
“The Indus River played a crucial role in the growth of the ancient Indus Valley civilization by offering a consistent water source for agriculture, trade, and communication,” stated Dr. Bimal Mishra from the Indian Institute of Technology Gandhinagar and his colleagues.
“Civilizations prospered near the Indus River and its tributaries approximately 5,000 years ago and evolved over time.”
“The mature Harappan phase (4,500 to 3,900 years ago) was marked by meticulously planned cities, advanced water management techniques, and an intricate writing system.”
“However, post 3,900 years ago, the Harappan civilization began to deteriorate and eventually fell into decline.”
“The causes for this decline are still under discussion. Potential factors encompass shifts in river dynamics influenced by climate change, ocean retreat, drought, flooding, and alterations in social and political structures.”
“Understanding ancient hydroclimatic events and their impact on societies provides vital insights into the susceptibility of complex societies to environmental pressures.”
For this research, the authors simulated climate patterns in the Indus Valley from 5,000 to 3,000 years ago.
They integrated these findings with various indirect climate indicators, including the geochemistry of stalactites and stalagmites from two caves in India and water level data from five lakes in northwestern India.
The results indicated that temperatures rose by approximately 0.5 degrees Celsius during this time, while average annual precipitation in the region decreased by 10% to 20%.
They were able to identify four significant drought periods lasting over 85 years between 4,450 and 3,400 years ago, impacting 65% to 91% of the Indus Valley area.
“These droughts affected the selection of settlement locations in the Indus Valley Civilization,” the researchers noted.
“From 5,000 to 4,500 years ago, settlements were primarily situated in regions with abundant rainfall.”
“However, after 4,500 years ago, they shifted closer to the Indus River as drought conditions began to limit water availability.”
“The last identified drought, lasting 113 years from 3,531 to 3,418 years ago, corresponds with archaeological evidence of significant urbanization in the Indus Valley Civilization.”
“Instead of collapsing abruptly due to sudden climate changes, the Indus civilization likely faced a gradual decline, with extended drought being a key factor,” concluded the researchers.
Their study was published on November 27 in the journal Communication Earth and Environment.
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H. Solanki et al. 2025. River drought forcing Harappan metamorphosis. Communication Earth and Environment 6,926; doi: 10.1038/s43247-025-02901-1
The Antarctic is experiencing higher temperatures than expected
Eyal Bartov / Alamy
Since early September, air temperatures in Antarctica have soared beyond 35°C (63°F), accompanied by a significant reduction in wind speeds, with ozone depletion halting unexpectedly.
This scale of change is typically anticipated only every two decades, according to Martin Zicker from the University of New South Wales, Sydney, Australia. However, such phenomena appear to be occurring with increasing frequency, with similar transient disruptions noted last year, alongside more severe occurrences in both 2019 and 2002.
Jucker observes that four of these events have appeared within just 25 years, indicating ongoing unpredictable shifts in the global climate system.
Typically, air temperatures in Antarctica hover around -55°C (-67°F), but have been unrelentingly rising to -20°C (-4°F) since September 5th. Although still extremely cold, this shift has resulted in the polar vortex winds decreasing relatively gently to 100 km/h.
While this warming event has not yet met the formal criteria for sudden stratospheric warming, Jucker notes that for that classification to apply, the winds need to cease entirely—not just for weeks but in response to the warmth itself. He warns that the repercussions in the Southern Hemisphere could be dramatic over the ensuing months.
Initially, Australian meteorologists forecast a wetter spring than normal, but they are now signaling potential impacts from a powerful system over western Australia, likely pushing the region into warmer and drier conditions.
Unusual weather patterns may persist. Jucker indicates that one possible scenario could see a return of the polar vortex, bringing atmospheric temperatures back to their typical averages.
Conversely, the temperature anomaly might continue, with expectations of further increases up to 20°C (36°F). This could lead to erratic weather in the higher latitudes of the Southern Hemisphere.
The reason behind this anomaly remains unclear scientifically, but Jucker asserts that it’s almost guaranteed that rising sea surface temperatures in the Pacific Ocean, possibly increasing by 1°C (1.8°F) to 3.6°F, are connected.
“The presence of three significant typhoons in the Pacific can be traced to these warmer sea temperatures,” remarks Jucker. “We’ve witnessed markedly strange weather patterns over the last two years, coinciding with this substantial rise in ocean temperatures.”
Edward Dodridge from the University of Tasmania in Hobart, Australia, emphasizes the array of extreme changes occurring at the southernmost point of the globe. Recent years have seen a dramatic deceleration in sea ice loss, heatwaves, widespread breeding failures among Emperor Penguin colonies, and shifts in Antarctic circulation.
“Antarctica continues to astonish us,” he notes. “While each change is noteworthy on its own, my primary concern is witnessing shifts that not only reinforce themselves but also ripple through various components of the Antarctic ecosystem.”
“The loss of summer sea ice facilitates the fracturing of ice shelves, which in turn accelerates ocean warming. This warmer seawater melts the remaining ice shelves at an increased rate.”
Fire and Ice: Exploring Iceland
Experience thrilling days filled with volcanic and geological exploration. Discover Iceland’s stunning landscapes and seize the evening chance to witness the Aurora Borealis in October.
Wavy polar jet streams can lead to icy storms extending further south
Images of the history of science / Alamy Stock Photos
Recent studies indicate that the increasingly erratic winter weather in the Northern Hemisphere is not solely due to more pronounced wavy polar jet streams.
The Arctic jet stream functions as a wind current that helps to maintain the balance between temperate and cold air in the Arctic region.
For over a decade, some researchers have engaged in discussions regarding the effects of the warm Arctic on the jet stream. This warming has reportedly intensified in winter, leading to severe storms that carry snow and ice much further south than usual. However, doubts persist about this theory.
Testing this hypothesis has proven challenging due to limited satellite data and the natural fluctuations of the jet stream during winter.
Researchers like Erich Osterberg from Dartmouth University have sought to determine whether the recent behavior of the jet stream deviates from the long-term average.
Since satellite observations of the jet stream began only in 1979, researchers leveraged temperature and atmospheric pressure data extending back to 1901 to reconstruct the movement of polar jets across the United States throughout the 20th century.
They discovered that polar jets exhibited wave-like patterns during various periods, indicating that the current erratic behavior may not be unprecedented. In fact, at times, the winter jet stream was even more undulating than it is today. “What we’re observing with the jet stream now is not particularly unusual when you consider the broader context of the 20th century,” Osterberg states.
The winters in the Northern Hemisphere are becoming warmer and wetter, a trend emphasized by Osterberg even as climate change continues to provoke more severe storms and precipitation. “It’s evident that climate change is influencing extreme weather events significantly,” he remarks. “However, in the context of winter jet streams, these changes don’t appear to be a fundamental factor.”
Similarly, Tim Woolling from Oxford University highlights the importance of long-term data in identifying shifts in polar jet stream behavior, noting its significant variability in the short to medium term. “Utilizing extensive data records and diverse methodologies reveals that today’s North American winter jet patterns are not necessarily worse than in previous decades,” he explains.
Contrastingly, during the Northern Hemisphere summer, emerging evidence suggests that climate change has elevated tropical temperatures, leading to broader polar waves in warmer months. “In summer, it seems that the jet stream undergoes a fundamental shift in behavior, with larger waves leading to intense heat waves, droughts, and wildfires,” Osterberg adds. “This phenomenon appears to be linked to climate change.”
Elon Musk stated on Monday that X was hit by a “massive cyberattack,” causing intermittent service disruptions that affected social media networks throughout the day. The platform, formerly known as Twitter, was unresponsive for many users as posts failed to load.
“We face attacks every day, but this one was well-resourced,” said the platform’s CEO. He posted, “Large, coordinated groups and/or countries are involved.”
Down detector, a website monitoring for outages, showed a spike in thousands of outage reports around 5:45 am on various platforms. Another surge in reported outages occurred around noon, with most issues happening on the company’s mobile app. Tweets that failed to display showed a “something went wrong” message prompting users to try reloading.
The world’s richest man did not provide evidence for his claim. His statements were in response to cryptocurrency influencers suggesting a pause following other resistance to Musk’s ventures. Protests against the “Ministry of Government Efficiency” initiative resulted in vandalism against Musk’s leadership and Tesla dealers in the previous week.
The CEO of SpaceX, who acquired Twitter for $44 billion in 2022, alleged that the previous platform outage was due to a cyberattack. Musk previously claimed a “massive DDOS attack” caused the crash of his live-streamed interview with Donald Trump last year, although company sources later told The Verge there was no attack.
The X outage adds to the challenges facing Musk’s businesses and initiatives. A SpaceX rocket exploded in flight near the Bahamas on Friday, scattering debris. “Tesla Takedown” protests across the nation targeted Tesla dealers, with owners selling vehicles, and the company’s stock prices hitting a low on Monday. Trump also had a heated meeting with Musk and his Cabinet Secretary, hinting at curbing Musk’s influence against government officials who fired many from various agencies.
Black hole is a spots in the universe that cannot be escaped by light because the gravity is very strong. One of the black holes that confuses astronomers is how large they are. Researchers explain one category of black holes over 100,000 to 10,000,000,000,000,000 times, like the sun. Super Massive Black Hall。 These black holes are very large, so Whole galaxy! It generally exists in the center of the galaxy, including ourselves milky wayOur thing is a modest 4,000,000 sun. Scientists are wondering if the universe, which was formed only in the universe, has grown very much. 13.7 billion years ago Big bang.
Gas and dust falling in the black hole, Light flashing attachedIt also occurs slowly to explain the growth of the ultra -high MASSIVE black hole. For example, our Galaxy's super huge black hole grows with just one sun. 3,000 years。 However, assuming that the black hole grows at a constant speed, the huge hole has had to increase the mass of the sun more than the value of the sun every year since the Big Bang.
To solve this problem, astronomers theorize how Black Hall was born in the early universe. Super Massive Black Hall requires a good start compared to the conventional black hole cousin. There is a sun from 10S to 100 years。 Thus, astronomers assume that many black holes and many 100,000 solar sun must have been formed early in the universe. They call these early black holes seed。 Roughly speaking, astronomers propose two potential origin, a black hole species. Giant clouds of dust It collapses directly into the black hole Population III star explosion.
Columbia University's astronomers have recently explored how the seeds have grown to grow to today's size, and how they have appeared in a very large black hole. The first step of the astronomer was to find an appropriate formula to calculate the initial quantity of black holes. Researchers have indicated that black hole growth is almost completely exponential. Therefore, this astronomer began with a modified index growth ceremony, like the calculation. Compound interest。 He took this type of derivative and determined how fast the black hole grew. Astronomers have assumed that all super -large black holes formed between the Big Bangs between 100 and 200 million years will be formed.
Astronomers selected 132,539 ultra -large black holes with sufficiently measured mass, and calculated the characteristics of seeds using his new formula. He discovered that 54 % of the seeds could be less than 350 times the mass of the sun, and could occur from the explosion of the individual group III stars. Another 40 % was 350-2,000 times the mass of the sun, and only 2,000 to 30,000 times the mass of the sun was about 6 %. He suggested that the latter two categories could cause small seeds that fuse immediately after being formed. He pointed out that these results did not directly exclude the collapse of the dust in black holes, indicating that there was no need to explain the ultra -large black hole we are looking at today. I mentioned.
Astronomers suggested that these ultra -large black holes have accumulated most of their mass in the first 1.5 billion years of the universe. 。 He explained that the universe was very dense at the time. Later, the galaxies were approaching each other, so a large amount of materials could fall into the black hole. He concludes that the ultra -large black hole is ultimately the relic of the primitive universe, and has been in a very different way than today's organic stars, dust clouds, and galaxies. I did it.
In certain areas of the world, such as Canada’s Hudson Bay, gravity is slightly lower than in other areas.
This is because an object with more mass has more gravity, and since Earth’s mass is not uniform, gravity varies from place to place. However, you need a very accurate scale to notice it. Hudson Bay’s gravity is about four thousandths of a percent lower than Earth’s average.
When scientists discovered this anomaly in the 1960s, they developed two theories to explain it. The first is that the Earth’s crust is still recovering from the last Ice Age.
About 20,000 years ago, the huge Laurentide ice sheet covered North America. The weight of the ice, which was more than 3 kilometers (almost 2 miles) thick in places, pushed down on the continent’s crust.
When the Ice Age ended, the Laurentide melted rapidly, but the Earth’s crust slowly returned to normal. It rebounds by about 12 mm (0.5 inch) each year, meaning it will take another 300,000 years to return to its original position. This indentation left in the Earth’s crust means that Hudson Bay has slightly less mass and therefore slightly less gravity.
The second theory concerns the movement of the mantle beneath the Earth’s crust.
The mantle is made of molten rock heated by the Earth’s core. It rises over geological time scales and then sinks again as it cools. This creates convection currents that move the plates. Ocean currents can also pull continents downward, slightly reducing mass and gravity in the area.
Satellite measurements in 2002 revealed both theories to be correct. The Hudson Bay gravity anomaly is caused by a combination of mantle convection and the legacy of the Laurentide ice sheet. Therefore, even after the Earth’s crust has fully rebounded, gravity in this part of the world will remain slightly lower than average.
This article answers the question (asked by Victor Gregory via email): “Is it true that people in Canada weigh less?” If you have any questions, please email us at:questions@sciencefocus.com or send us a messagefacebook,×orInstagramPage (remember to include your name and location).
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aShortly after posting Pushing Buttons last week, big gaming news broke: Sony was pulling the plug on hero shooter Concord just two weeks after launch, citing reasons that no one was playing it. Refunds were being offered to everyone who purchased it on PlayStation 5 and PC, leaving the game’s future uncertain.
It’s a brutal series of events. Sony acquired Firewalk Studios, the makers of Concorde, in 2023. Concorde was an expensive game that was in development for eight years, with a custom cinematic and a long-term plan that cost over $100 million to develop. Estimates suggest that fewer than 25,000 copies were sold in the first two weeks of release. This is shocking compared to other bad news for developers and studios this year.
Many It is written The question remains as to why Concorde was such a huge flop. As Keith Stewart pointed out in his review of the game, it entered a crowded genre of hero shooters, where many players already had favorites (Overwatch, Valorant, Apex Legends, etc.). Sony’s marketing for the game also seemed to flop, with very few people knowing about Concorde before it came out (I almost didn’t, but it’s my job to know about these things). Criticism was also leveled at the characters and design, which were generic and lacked any particularly interesting gameplay ideas.
Concord’s failure is emblematic of an existential problem in modern game development: Games are expensive and take so long to make that moment they can be missed years before a game is released. This makes publishers risk-averse, but simply trying to recreate something popular means it will be outdated by the time it’s finished.
I don’t want to play a game that takes years to play…Black Myth: Wukong. Photo: undefined/Game Science
Concord isn’t the first high-profile multiplayer flop of the year. Warner Bros.’ Suicide Squad: Kill the Justice League also disappointed publishers with poor sales and disappointed players by shoehorning a potentially fun game into a live-service multiplayer model. Sega’s Foamstars went completely unnoticed. And let’s not forget Sega’s live-service shooter Hyenas. Cancelled This was just a few months before the scheduled release.
My sense is that people just don’t have time to play games that last forever anymore. Destiny, one of the first of the current generation of permanent live-service games aimed at keeping players playing for years, celebrated its 10th anniversary this week. The game has become part of the lives and habits of millions of people. Overwatch, Fortnite, and even the decades-old World of Warcraft dominate in their genres. What will it take to get these players to abandon the game for a new one or add a new one to their spare time? And with these types of games, people aren’t just abandoning the game, they’re abandoning their friends.
The proliferation of live service games reminds me of the time in the 2000s when nearly every publisher was trying to make a massively multiplayer online game like World of Warcraft. Every day we got a press release saying someone had secured millions of dollars in funding for a new Warcraft killer. Some of the resulting games were good (Guild Wars, to name one), but most were only moderately successful at best. Online games areSuccess isn’t easy. It never was.
It’s surprising that this game is coming out so soon after the sales surge of Black Myth: Wukong, a single-player only game. As I wrote last week, many factors contributed to Wukong’s success, but still, there is a huge demand for this game, and by extension, single-player games in general. Personally, I don’t want a game that takes years to play. I want a game that wants to say something, to convey an experience, and that eventually ends. Games where the artistry is reflected in the game. in front That business model.
This is partly a matter of preference. There’s clearly a huge market for live-service multiplayer games; it’s just that most people are already playing them. There’s no way there’s an untapped market for millions of players who crave hero shooters and battle royale games but haven’t yet found the right fit. It’s time for publishers to try something new instead.
What to Play
It’s also great for kids… Photography: Good Feel Co.
My family is still crazy about Astro Bot. My youngest son wakes me up every morning telling me about his favorite power-up (his favorite is the “Frog Punch”). But I wanted a break, so I took a long train ride recently. Bakel It’s a Japanese-style action platform game in the vein of the forgotten 1990s series Ganbare Goemon, which means absolutely nothing to 98% of people – it means defeating beautifully animated enemies. Yokai Use your drumstick to run through a world of manga-style depictions of Japanese towns and landscapes.
The difficulty level is clearly geared towards kids, so I barely had any trouble playing through the first few levels, but it’s still a welcome time-warp platformer that reminded me of the screenshots of similar Japanese games I used to pore over in Nintendo magazines back in the ’90s.
Available: PC, Nintendo Switch Estimated play time: 10 hr
An eternal conversation…Destiny 2. Photo: Activision
In more positive news for Sony, the long-awaited PS5 Pro It’s finally been announced, and for an extra £200 on top of the current system price you get an enhanced tech spec, a 2TB solid-state drive and more.
As mentioned above, Bungie’s space opera shooter destiny It turns 10 this week, and as Christian Donlan writes in his anniversary essay, the game is about everytime There’s something to be said for this, and it’s not just one of the first ever-lasting games, it’s an ever-lasting conversation.
The Mystery of Rubber Keysa new film about the development of ZX Spectrumwill be released early next month.
What to click on
Question Block
Baldur’s Gate 3 is best played on PC. Photo: Larian Studios
leader Maisie Question of the week:
After years of enjoying gaming on the Switch, I decided to broaden my horizons and bought a PS4 and a gaming laptop. The PS4 is great, but I’m having trouble getting Steam games to start. Working at a desk is different than lounging on the couch next to your husband. Do you have any tips for making PC gaming more fun and less like work?
I feel the exact same way about PC gaming. I hate sitting at a desk playing games. As a teenager I would play endless hours of Rollercoaster Tycoon, The Sims, and Age of Empires II after school, but now I sit at a desk all day. Not only is it the last thing I want to do after work, it’s also bad for my health. But I’ve been playing a lot of PC games lately, because I can play most games with a Bluetooth-enabled controller by connecting it to my TV with an HDMI cable. PS4 Controller You can use any Xbox controller. I Xbox One Pad I use it for PC gaming now, but for many years I used an old, cheap, second-hand wired Xbox 360 one. Steam Deck It’s a game changer, so I highly recommend saving up and buying one.
For PC-exclusive games, that might seem like a worthwhile investment — almost all games are cross-platform these days — but… Baldur’s Gate 3 It really is great to play on PC, and if playing on PC doesn’t make you a fan of the keyboard and mouse, then nothing will.
If you have a question for Question Block, or anything else you’d like to say about the newsletter, please click “Reply” or email us at pushingbuttons@theguardian.com.
The asteroid, called the Chicxulub impactor, was a carbonaceous asteroid that formed outside the orbit of Jupiter. New Paper Published in the journal Science.
Ankylosaurus magniventrisA Tyrannosaurus, a type of large armored dinosaur, witnessed the impact of an asteroid that fell on the Yucatan Peninsula 66 million years ago. Image by Fabio Manucci.
About 66 million years ago, a 10-kilometer-wide asteroid struck Earth near what is now a small town called Chicxulub in Mexico.
This impact released incredible amounts of climate-changing gases into the atmosphere, setting off a chain of events that led to the extinction of the non-avian dinosaurs and 75% of life on Earth.
Evidence includes the presence of high concentrations of platinum group elements (PGE) in the Cretaceous-Paleogene boundary layer, including iridium, ruthenium, osmium, rhodium, platinum, and palladium, which are rare on Earth but common in meteorites.
These elevated PGE levels have been found worldwide, suggesting that the impact spread debris around the world.
Some have proposed large-scale volcanism in the Deccan Traps igneous province of India as an alternative source of PGEs, but the specific PGE ratios at the Cretaceous-Paleogene boundary are more consistent with an asteroid impact than volcanism.
However, little is known about the nature of the Chicxulub impactor, including its composition and extraterrestrial origin.
To answer these questions, Dr Mario Fischer-Gödde from the University of Cologne and his colleagues measured ruthenium isotopes in samples taken from three sites at the Cretaceous-Palaeogene boundary.
For comparison, the team also analysed samples from five other impacts that occurred between 36 million and 470 million years ago, an ancient impact spherule from 3.5 to 3.2 billion years ago, and two carbonaceous meteorites.
The researchers found that the ruthenium isotope signature of samples taken from the Cretaceous-Paleogene boundary was uniform and matched very closely to that of carbonaceous chondrites rather than those from Earth or other types of meteorites, suggesting that the Chicxulub impactor likely came from a carbonaceous-type asteroid that formed in the outer solar system.
The other five impact structures have isotopic signatures more consistent with silicic asteroids that formed closer to the Sun.
The ancient spherulitic samples are consistent with a carbonaceous asteroid impact during the final stages of Earth's accretion.
“The composition of this asteroid is consistent with that of carbonaceous asteroids that formed outside Jupiter's orbit during the formation of the solar system,” Dr Fischer-Gödde said.
“Asteroid impacts like Chicxulub turn out to be very rare and unique events in geological time,” said Professor Carsten Müncher from the University of Cologne.
“The fate of the dinosaurs and many other species was sealed by this object that came from the outer solar system.”
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Mario Fischer-Gedde others2024. Ruthenium isotopes indicate that the Chicxulub impactor was a carbonaceous asteroid. Science 385 (6710): 752-756; doi: 10.1126/science.adk4868
The asteroid, called the Chicxulub impactor, was a carbonaceous asteroid that formed outside the orbit of Jupiter. New Paper Published in the journal Science.
Ankylosaurus magniventrisA Tyrannosaurus, a type of large armored dinosaur, witnessed the impact of an asteroid that fell on the Yucatan Peninsula 66 million years ago. Image by Fabio Manucci.
About 66 million years ago, a 10-kilometer-wide asteroid struck Earth near what is now a small town called Chicxulub in Mexico.
This impact released incredible amounts of climate-changing gases into the atmosphere, setting off a chain of events that led to the extinction of the non-avian dinosaurs and 75% of life on Earth.
Evidence includes the presence of high concentrations of platinum group elements (PGE) in the Cretaceous-Paleogene boundary layer, including iridium, ruthenium, osmium, rhodium, platinum, and palladium, which are rare on Earth but common in meteorites.
These elevated PGE levels have been found worldwide, suggesting that the impact spread debris around the world.
Some have proposed large-scale volcanism in the Deccan Traps igneous province of India as an alternative source of PGEs, but the specific PGE ratios at the Cretaceous-Paleogene boundary are more consistent with an asteroid impact than volcanism.
However, little is known about the nature of the Chicxulub impactor, including its composition and extraterrestrial origin.
To answer these questions, Dr Mario Fischer-Gödde from the University of Cologne and his colleagues measured ruthenium isotopes in samples taken from three sites at the Cretaceous-Palaeogene boundary.
For comparison, the team also analysed samples from five other impacts that occurred between 36 million and 470 million years ago, an ancient impact spherule from 3.5 to 3.2 billion years ago, and two carbonaceous meteorites.
The researchers found that the ruthenium isotope signature of samples taken from the Cretaceous-Paleogene boundary was uniform and matched very closely to that of carbonaceous chondrites rather than those from Earth or other types of meteorites, suggesting that the Chicxulub impactor likely came from a carbonaceous-type asteroid that formed in the outer solar system.
The other five impact structures have isotopic signatures more consistent with silicic asteroids that formed closer to the Sun.
The ancient spherulitic samples are consistent with a carbonaceous asteroid impact during the final stages of Earth's accretion.
“The composition of this asteroid is consistent with that of carbonaceous asteroids that formed outside Jupiter's orbit during the formation of the solar system,” Dr Fischer-Gödde said.
“Asteroid impacts like Chicxulub turn out to be very rare and unique events in geological time,” said Professor Carsten Müncher from the University of Cologne.
“The fate of the dinosaurs and many other species was sealed by this object that came from the outer solar system.”
_____
Mario Fischer-Gedde others2024. Ruthenium isotopes indicate that the Chicxulub impactor was a carbonaceous asteroid. Science 385 (6710): 752-756; doi: 10.1126/science.adk4868
The flooding is caused by the retreat of smaller glaciers near Mendenhall Glacier, a result of global warming that creates a basin filled with rain and melting snow each spring and summer. When the water pressure is strong enough, it can seep under or around the ice dams formed by Mendenhall Glacier and flow into Mendenhall Lake and eventually the Mendenhall River.
Since 2011, this phenomenon has also led to flooding of roads and homes near lakes and rivers. Last year’s floods engulfed large areas, causing riverbanks to collapse, homes to be flooded, and at least one house to be submerged in the swiftly moving waters.
Authorities indicated that the extent of this week’s flooding was unprecedented, leaving residents distressed as they attempted to salvage furniture, books, and other possessions in the midst of warm, sunny weather. Debris such as garbage bags, wood, boxes, wet insulation, carpets, and other items were stacked along road curbs on Wednesday. Street sweepers were busy clearing the muddy aftermath left by the receded water.
Eran Hood, an environmental science professor at the University of Alaska Southeast who has spent years studying Mendenhall Glacier, mentioned that while the basin was created by glacier retreat, climate change has minimal impact on the annual fluctuations in flood levels in Juneau.
A family is rescued from flooding on the Mendenhall River in Juneau, Alaska, on August 6.Sean Maguire/Anchorage Daily News via The Associated Press
He expressed, “It’s evident that these floods will persist over several decades, but predicting the size of future floods is challenging without more precise glacier dynamics modeling, due to numerous factors that influence their magnitude.”
Hood mentioned that at some point, Mendenhall Glacier will shrink and become too thin to act as a barrier.
The flooding serves as a stark reminder of the global hazards posed by failures of snow and ice dams, a concept known as jokulhlaup, which is relatively unfamiliar in the United States. Threatening approximately 15 million people around the world.
Residents remove wet drywall and insulation from the first floor of a home after the Mendenhall River flooded in Juneau, Alaska, on August 6.Mark Lester/nchorage Daily News via The Associated Press
Juneau, a city with about 30,000 inhabitants in southeast Alaska, can only be accessed by plane or boat. Despite peak tourist season, the city is currently facing a housing shortage that could limit temporary accommodations for flood victims. Rental car options in Juneau are also limited for those whose vehicles were affected by the flooding.
Authorities reported that the Mendenhall River hit a new record high of 15.99 feet (4.9 meters), approximately a foot higher than last year’s floods, and the water extended further into Mendenhall Canyon. Some homes beyond flood-prone areas were reached by the water, and the canyon is situated about a 15-20 minute drive from downtown Juneau.
Alyssa Fisher shared that she didn’t anticipate flooding in her area when she went to bed on Monday night. However, her father woke her up over FaceTime a few hours later to inform her of rising water levels outside. She moved his car to higher ground, grabbed essential items, and relocated to a local school shelter with her two children, ages 4 and 8, along with their pets. She noticed that the truck’s license plate had been bent by the floodwaters.
Ever wondered if any moons in the solar system have a dense atmosphere like Earth? Currently, scientists believe that Saturn’s moon Titan is the only one with such an atmosphere. Despite being 2.5 times smaller than Earth, Titan has an atmospheric pressure 1.5 times greater than Earth’s. Studies of Titan’s atmosphere from outside the solar system have shown that it consists of around 94% nitrogen, 6% methane, 0.1% hydrogen, and small amounts of complex organic molecules. The Huygens mission data provides more insight into this.
Initially, scientists thought that Titan’s haze formed through the breakdown and recombination of nitrogen and methane by sunlight. However, this explanation couldn’t account for the presence of complex organic molecules which require high temperatures to form. Recent research suggests that these molecules may have originated during a meteorite impact event in Titan’s atmosphere, particularly due to the proximity of Titan to Saturn’s E ring which disperses organic material from moons like Enceladus.
To test this new theory, researchers at Princeton University created a model to predict the formation of molecules during meteorite impacts in Titan’s atmosphere. By combining data from observations of Saturn’s rings and Titan’s atmospheric chemistry from the Huygens probe, they estimated the types of organic molecules that could result from these impacts. They found that only meteorites larger than 0.02 grams could trigger such events in Titan’s atmosphere, with material mostly originating from atolls surrounding the solar system.
The team also identified a hot zone known as the “Cylindrical shock wave” around the falling meteorite, reaching temperatures of 10,000 K. This wave could facilitate the synthesis of complex organic molecules at lower temperatures in the region surrounding the impact. Meteorites falling from Enceladus are suggested to contribute significantly to Titan’s organic-rich haze layer, particularly at altitudes where shock waves are most efficient in synthesizing organic molecules.
The researchers proposed that observations from future missions, such as Dragonfly, could further validate their models by studying the frequency of medium-sized meteorite impacts on Titan. These observations could provide more insights into the formation of Titan’s unique atmosphere and iconic haze layer.
Jet engines emit large amounts of ultrafine particles
Aerovista Luchtfotografie/Shutterstock
The health of more than 50 million people living within 20 kilometres of Europe's busiest airport is being harmed by high levels of ultrafine particle pollution from jet engines, according to a report. the study It was commissioned by campaign group Transport & Environment (T&E).
Several Other studies It says ultrafine particles can increase the risk of respiratory diseases, cardiovascular diseases, neurological diseases, diabetes and pregnancy problems. Darn Fun Setters His team, working at the Dutch consultancy CE Delft, are using these studies to try to estimate the impact for Europe as a whole.
But ultrafine particle pollution is a less-studied aspect of air pollution and there is a lot of uncertainty: “There is little research in this area and the evidence is often inconclusive,” Van Seters said.
Most research on particulate air pollution has focused on particles smaller than 2.5 micrometers in diameter, so-called PM2.5. Ultrafine particles are particles smaller than 0.1 micrometers in diameter.
“They are very dangerous because they are so small and can get very deep into the human body.” Carlos Lopez de la Osa At T&E.
Jet engines emit more ultrafine particles than other types of engines, so people who live or work near airports are most likely to be exposed to this form of air pollution, but there are no effective limits on its levels.
Ultrafine particles are a type of PM2.5, but PM2.5 limits are set for the total mass of particles per cubic metre of air. Ultrafine particles are so small that even a huge number of particles per cubic metre would not exceed the PM2.5 limit.
In fact, there's very little monitoring of ultrafine particle levels, says Lopez de la Osa. “What we have are mostly regional studies around individual airports like Zurich, Amsterdam, Berlin, Los Angeles,” he says. “We don't have a comprehensive view, and that's one of the main reasons we decided to launch this study.”
To estimate the impact across Europe, van Seters and his colleagues first estimated ultrafine particle pollution levels around the continent's 32 busiest airports, based on figures from surveys of individual airports. The team assumed that ultrafine particle pollution increases linearly with the number of flights and did not take wind patterns into account.
Next, based on studies looking at health effects, the researchers estimated that ultrafine particle pollution near 32 airports was responsible for an additional 280,000 cases of hypertension, 330,000 cases of diabetes, and 18,000 cases of dementia over the years.
“This is a first-order estimate based on extrapolation, and we need to do epidemiological studies to get more precise estimates,” Van Seters said.
But he thinks that, if anything, is an underestimate because the study only looked at 32 airports and people living within 20 kilometres, and excluded people who work at the airports.
In terms of population at risk, Orly Airport near Paris tops the list, with more than six million people living within 20 kilometers of the airport, while London's Heathrow Airport comes in fourth, with more than three million people living within the airport's vicinity.
The research team's estimates of health effects rely heavily on a study carried out in 2022 at Schiphol Airport near Amsterdam. Nicole Jansen Contacted by CE Delft, Janssen and her colleagues at the National Institute for Public Health and the Environment in the Netherlands said they advised researchers not to try to quantify the impact in this way because of large uncertainties.
But they agree that more research is needed: “We would underscore our recommendation to further investigate the risk of ultrafine particles from aircraft around other international airports,” Janssen said.
There are ways to reduce ultrafine particle pollution levels, says Christina Toth of T&E. Jet fuel can be improved to reduce ultrafine particle emissions, for example by reducing its sulfur content. So-called “sustainable aviation fuels” (SAF) also reduce ultrafine particle pollution.
“Unfortunately, we know it will be a long time before SAF can be produced at scale and be effective,” Toth says.
Limiting airport expansion and flight frequencies and encouraging alternative modes of transport would help, and would also limit flying's impact on the climate.
In Los Angeles, air pollution from cars and human activity is exacerbated by the city's factories emitting chemicals in response to rising temperatures and drought.
“It's difficult to control emissions from factories, [human-caused] “Some.” Eva Fannerstill At the Forschungszentrum Jülich, a German research institute.
From blooming jacaranda trees to fragrant eucalyptus, many plants emit compounds called terpenoids. To plants, these act as chemical signals and function as antioxidants. But in the atmosphere, these volatile organic compounds (VOCs) react with other pollutants to create harmful ozone and particulate pollution called PM2.5.
In areas where cleaner vehicles and electricity generation have reduced man-made sources of air pollution, industrial emissions have begun to play a larger role, but by how much is unclear.
Vannerstill and her colleagues flew planes over Los Angeles over several days in June 2021 to measure the city's VOC emissions. Using an on-board mass spectrometer, the researchers identified concentrations of more than 400 VOCs in the air. Simultaneous 3D measurements of wind speed allowed them to separate molecules rising from the city from those blowing in from elsewhere.
The researchers found that terpenoids made up the majority of VOC emissions in many parts of the city, especially in areas with the most vegetation and on the hottest days. When temperatures exceeded 30°C (86°F), terpenoids made up the majority of emissions, even in the downtown area, where vegetation was sparse and people were more likely to be present.
It's unclear exactly why plants release more terpenoids when temperatures rise, but it could be a response to heat or water stress, Pfannerstill said. Higher temperatures also increase VOC emissions associated with anthropogenic sources, such as gasoline, paint, and even scented personal care products like deodorant and hairspray, possibly due to increased evaporation rates.
The contribution of these personal-care products in particular spikes with population density, suggesting a small but direct link between urban air pollution and citizens' beauty habits. “It's measurable,” Vannerstill says.
The observed relationship between heat and emissions also suggests a pathway through which climate change could exacerbate air pollution: in Los Angeles, the researchers found that a 3°C warming predicted for the city by mid-century could double the impact of VOCs on ozone formation; and its impact on PM2.5 pollution could increase by 40%.
“This direct observation is crucial for building good models to predict what air pollution will be like tomorrow or a few years from now.” Matthew Cogon Jonathan Myers, environmental secretary at the National Oceanic and Atmospheric Administration, said the increase in emissions from factories underscores the importance of further reducing man-made sources of air pollution that react with VOCs, such as nitrous oxide, which comes from burning fossil fuels.
The types of plants planted in cities also have an impact. Roissyne Comanet It's an important consideration as more cities pursue urban greening initiatives. “Vegetation is important,” she says at Columbia University in New York.
Parts of the Middle East were hit by heavy rains on Tuesday, leading to school closures in the United Arab Emirates and flooding at Dubai International Airport. Oman has reported at least 18 deaths in recent days due to the inclement weather.
The storm caused flooding on roads and dangerous conditions throughout the region. This area is typically dry and not used to heavy rainfall or flash floods.
Airport officials confirmed that flights to Dubai Airport had to be diverted temporarily due to the unusual weather events in the UAE. Statement
Cars drive through flooded roads in Dubai on Tuesday after a heavy rainstorm. Abdel Hadi Ramahi/Reuters
Video footage showed Dubai’s tarmac flooded, with planes navigating through floodwaters and support vehicles almost submerged, according to reports from Saudi Arabia’s Al Arabiya news agency.
Over 4.7 inches of rain fell in a day in the UAE, causing road and property flooding in Dubai. Associated Press reported.
The UAE’s National Emergency, Crisis and Disaster Management Authority advised people to stay home. Commenting on X’s post, they suggested parking vehicles in safe, elevated areas away from flood-prone zones.
Pedestrians cross a flooded road in Dubai on Tuesday. Anadolu (via Getty Images)
Private schools in the UAE were closed before the storm and government employees were advised to work remotely.
While the UAE is known for its dry climate, rain does occur occasionally during the winter.
In neighboring Oman, recent storms and heavy rain have led to the deaths of 10 school children and an adult driver in a flooded car, as reported by the Associated Press.
Other parts of the Middle East, such as Qatar and Saudi Arabia, also experienced unusually wet weather this week.
It’s unclear if recent storms have been influenced by global warming, but the warming atmosphere from climate change can hold more moisture, leading to stronger storms and heavier rainfall. Studies have suggested this possibility.
A map showing the expected surface temperature anomalies in 2024 if a strong El Niño event occurs.Blue dots indicate areas where record heat is expected
Ning Jiang et al., Scientific Reports
Climate models predict this year will be the hottest 12 months on record as El Niño conditions persist in the Caribbean, Bay of Bengal, South China Sea, Alaska and parts of the Amazon.
“These are places where the risk of extreme events is increased, and these extreme events are really harmful,” team members say. michael mcfaden NOAA Pacific Marine Environmental Laboratory, Seattle, Washington.
“They negatively impact human health and increase the risk of wildfires. And in the ocean, they increase the risk of marine heatwaves, damaging marine ecosystems, fisheries and corals,” he said. Masu.
Earth’s surface temperatures are currently at record highs in many parts of the world. The main reason is global warming caused by carbon emissions from burning fossil fuels. However, in addition to this, the strong El Niño phenomenon that started in mid-2023 is causing temperatures to rise further.
When an El Niño event occurs, warm water spreads across the surface of the Pacific Ocean toward South America. This vast area of warm water transfers large amounts of ocean heat to the atmosphere, causing an increase in surface temperature.
The reverse phase, known as La Niña, reverses this process. Cold water spreads over the surface of the Pacific Ocean away from South America, absorbing heat from the atmosphere and lowering the surface temperature.
This means that the Earth’s average surface temperature typically reaches record levels during El Niño periods and then drops during La Niña periods.
McFadden and his colleagues used a computer model that took into account aerosol pollution and volcanic eruptions in addition to El Niño to try to predict where in the world record heat would occur. Their regional forecast is the average surface temperature for the period from July 2023 to June 2024.
“Even if it’s not exactly timed to a specific season, there’s real value in having this kind of warning,” McFayden says. “It gives us a grace period to prepare how best to protect life, property, marine resources and economic development.”
The research team considered two scenarios: a strong El Niño and a milder El Niño. It’s now clear that a strong El Niño is occurring, and in fact, it’s likely to be in the top five strongest El Niños since 1950, McFadden said.
In this strong El Niño scenario, the research team predicts that the global average surface temperature from July 2023 to June 2024 would be 1.1°C to 1.2°C warmer than the 1951-1980 average. Masu.
this is Equivalent to a temperature above 1.4-1.5 °C average from 1850 to 1900, new scientist This is considered a pre-industrial benchmark. This suggests that the model is underestimating the temperature since it is already above this level. From January 2023 to January 2024, the Earth’s average surface temperature was more than 1.5 °C above the 1850-1900 average, and in January 2024 it was 1.7 °C above this level.
Temperature records have already been broken during El Niño, especially in the tropics, he said. maximiliano herrera, an independent climatologist who tracks extreme temperatures. “This is amazing,” he says. “We are experiencing record heat and it is inevitable.”
A woman who was undergoing surgery for colon cancer has been the victim of a wrongful death lawsuit in Florida this week. The lawsuit alleges that a robotic device caused damage to Sandra Sulzer’s small intestine, which led to her death. This happened after she experienced abdominal pain and fever following the surgery in September 2021. The extra procedures to close her lacerations were not enough to save her life, as she died in February 2022 due to small bowel injuries.
Sandra’s husband, Harvey Salzer, is seeking damages from Intuitive Surgical, the manufacturer of the device. The lawsuit claims that the company knew about the insulation problems in the robot that could cause internal organ burns, and yet failed to inform the users about the risk nor to disclose it to the public. It also asserts that Intuitive Surgical doesn’t properly train surgeons who use the device, the da Vinci, and that hospitals lack experience with robotic surgery.
According to the complaint, Intuitive has received thousands of reports of da Vinci-related injuries and defects, but “systematically underreports” injuries to the Food and Drug Administration. The company also stated in a 2014 Financial Report that it was a defendant in approximately 93 lawsuits at the time.
Many doctors support robotic surgery as a safe method, but there are discussions about whether it is more effective than traditional surgery. The technology aims to make procedures precise and less invasive, potentially leading to faster, less painful recovery.
Da Vinci Xi Surgical System.Provided by: Intuitive
A 2018 NBC News analysis revealed over 20,000 da Vinci-related adverse events over the past 10 years, as per reports from the FDA’s MAUDE database. More than a dozen patients spoke to NBC News about burns or injuries during procedures using da Vinci.
Intuitive defended the device’s safety, referring to scientific evidence supporting its effectiveness in over 15,000 studies.
of Sturtian “Snowball Earth” Ice Age (717 million to 661 million years ago) is considered the most extreme icehouse period in Earth’s history. In a new study, geologists from the University of Sydney and the University of Adelaide used plate tectonics modeling to identify the most likely cause of the Staats Ice Age.
Artist’s impression of “Snowball Earth”. Image credit: Oleg Kuznetsov, http://3depix.com / CC BY-SA 4.0.
“Imagine if the Earth almost completely froze over, which is exactly what happened about 700 million years ago,” said lead author Dr. Adriana Dutkiewicz, a researcher at the University of Sydney. .
“The Earth was covered in ice from the poles to the equator, and temperatures plummeted. But what caused this to happen is an open question.”
“We think we have now solved the mystery. Historically, volcanic carbon dioxide emissions have been low, driven by the weathering of large volcanic rock mountains in what is now Canada. It’s a process that absorbs carbon dioxide.”
Named after Charles Sturt, a 19th-century European colonial explorer of central Australia, the Sturtsian Ice Age spanned 717 million to 660 million years, long before dinosaurs and complex plants existed on land. It continued until ten thousand years ago.
“There are many possible causes for the trigger and end of this extreme ice age, but the most mysterious one is why it lasted 57 million years. It’s hard for humans to imagine,” Dr. Dutkiewicz said.
Dr. Dutkiewicz and his colleagues used a plate tectonics model that simultaneously shows the evolution of continents and ocean basins after the breakup of the ancient supercontinent Rodina.
They connected it to a computer model that calculates the outgassing of carbon dioxide from submarine volcanoes along mid-ocean ridges, where plates diverge and new oceanic crust is born.
They soon realized that the beginning of the Starch Ice Age correlated precisely with the lowest ever levels of volcanic carbon dioxide emissions.
Additionally, carbon dioxide flux remained relatively low throughout the ice age.
“At that time, there were no multicellular animals or land plants on Earth,” Dr. Dutkiewicz said.
“Greenhouse gas concentrations in the atmosphere were determined almost entirely by carbon dioxide emitted by volcanoes and by the weathering processes of silicate rocks that consume carbon dioxide.”
“At that time, geology ruled the climate,” said co-author Professor Dietmar Müller, a researcher at the University of Sydney.
“We think the Staats Ice Age began with a double whammy: plate tectonics realigned to minimize volcanic degassing, while at the same time Canada’s continental volcanic belt began to erode, removing carbon dioxide from the atmosphere. Consumed.”
“As a result, atmospheric carbon dioxide has fallen to levels that could begin an ice age. This is estimated to be less than 200 parts per million, less than half of today’s levels.”
The team’s current research raises interesting questions about the long-term future of the planet.
Recent theories suggest that over the next 250 million years, Earth will evolve toward Pangea Ultima, a supercontinent hot enough to wipe out mammals.
However, the Earth is currently on a trajectory where volcanic carbon dioxide emissions decrease as continental collisions increase and plate velocities decrease.
So perhaps Pangea Ultima will snowball again.
“Whatever the future holds, it is important to remember that geological climate changes of the type studied here occur very slowly,” Dr. Dutkiewicz said.
“According to NASA, human-induced climate change is occurring 10 times faster than ever before.”
Adriana Dutkiewicz other. The period of the Sturtian “Snowball Earth” ice age is associated with unusually low gas emissions at mid-ocean ridges. geology, published online on February 7, 2024. doi: 10.1130/G51669.1
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