Latest news with #atmosphere
Yahoo
a day ago
- General
- Yahoo
Solar 'cannonballs' may have stripped Mars of its water, long-awaited study reveals
When you buy through links on our articles, Future and its syndication partners may earn a commission. After nearly a decade in orbit, NASA's MAVEN spacecraft has, for the first time, directly observed the process that scientists had long suspected was responsible for stripping Mars of its atmosphere. The findings, published May 28 in the journal Science Advances, could help answer a longstanding question about how Mars transformed from a potentially habitable world with rivers and lakes into the mostly-frozen desert we see today. Although Mars today is dry, cold and virtually airless, its surface is carved with unmistakable evidence of a wetter past. Features resembling ancient river valleys, lake beds, and minerals that only form in the presence of water point to long-lived lakes, possibly even shallow seas, that flowed on Mars' surface billions of years ago. For liquid water to persist, however, Mars would have needed a much denser atmosphere to trap heat and sustain higher surface pressure. Understanding when and how that atmosphere vanished is essential to reconstructing Mars' climate evolution, and to determining how long the planet may have remained habitable. Over the past decade, scientists have gathered mounting evidence that solar wind — the constant stream of ionized particles emitted from the sun — and radiation stripped away much of the Martian atmosphere. Among the most significant mechanisms behind this erosion is a process called sputtering, where high-energy particles from solar wind collide with the planet's upper atmosphere. These collisions, in principle, transfer enough energy to neutral atoms and help break them free from the planet's gravitational pull, flinging them into space. "It's like doing a cannonball in a pool," Shannon Curry, the principal investigator of the MAVEN mission at the University of Colorado Boulder who led the new study, said in a statement. "The cannonball, in this case, is the heavy ions crashing into the atmosphere really fast and splashing neutral atoms and molecules out." While sputtering had long been suspected as a key player in Mars' climate evolution, this is the first time the process has been observed directly. Using nine years of data from the MAVEN spacecraft, Curry and her colleagues captured present-day sputtering on Mars. Related: NASA rover discovers out-of-place 'Skull' on Mars, and scientists are baffled By combining data from three of MAVEN's instruments, the researchers created a detailed map of argon, a noble gas, in Mars' upper atmosphere. Argon is an ideal tracer for this kind of atmospheric escape because it is chemically inert, heavy, and resistant to becoming charged. This makes it unlikely to interact with other atmospheric processes, meaning any significant loss of argon serves as a clear tracer of sputtering. Indeed, MAVEN detected the highest concentrations of argon at altitudes where solar wind particles collide with the Martian atmosphere, the new study reports. Its presence was much higher than where scientists would expect it to naturally waft under the planet's gravity, so the findings provide direct evidence that sputtering is actively lifting and removing the molecules from Mars, according to the new study. This process may even have been the driving force behind the loss of Mars' once-thick atmosphere and, with it, its ability to host liquid water on the surface, the study notes. MAVEN's data also revealed that this process occurs at a rate four times higher than previously predicted by models, according to the new study. It became more pronounced during solar storms, potentially offering a glimpse into how much more intense the process might have been during Mars' early history when the planet was more vulnerable to the sun's energy. RELATED STORIES —Scientists find hint of hidden liquid water ocean deep below Mars' surface —Lights on Mars! NASA rover photographs visible auroras on Red Planet for the first time —Perseverance rover rolls onto 'Crocodile' plateau on Mars to hunt for super-old rocks Scientists suspect this process was especially intense billions of years ago, when the sun was more active and Mars had already lost its protective magnetic field. Without that magnetic shield, the Martian atmosphere was left vulnerable to the full force of the solar wind, accelerating its erosion and pushing the planet past a tipping point where liquid water could no longer persist. "These results establish sputtering's role in the loss of Mars' atmosphere and in determining the history of water on Mars," Curry said in the statement. To fully determine whether sputtering was indeed the primary driver of Mars' long-term climate change, scientists will need to peer billions of years into the past using models, isotopic data, and ancient climate clues. Only then can they judge whether sputtering merely grazed the edges of Mars' atmosphere — or stripped it bare.
Yahoo
3 days ago
- Health
- Yahoo
An Extreme Drop in Oxygen Will Eventually Suffocate Most Life on Earth
For now, complex life flourishes on our planet thanks to its supply of oxygen. But Earth's atmosphere wasn't always like it is today, and scientists predict that in the future, it will revert back to one that's rich in methane and low in oxygen. Breathe easy though. This won't happen for probably another billion years or so. But when the change comes, it's going to happen fairly rapidly, according to research published in 2021. This shift will take the planet back to something like the state it was in before what's known as the Great Oxidation Event (GOE) around 2.4 billion years ago. "For many years, the lifespan of Earth's biosphere has been discussed based on scientific knowledge about the steadily brightening of the sun and global carbonate-silicate geochemical cycle," environmental scientist Kazumi Ozaki from Toho University in Japan said when the study was published. "One of the corollaries of such a theoretical framework is a continuous decline in atmospheric CO2 levels and global warming on geological timescales." The researchers say that atmospheric oxygen is unlikely to be a permanent feature of habitable worlds in general, which has implications for our efforts to detect signs of life further out in the Universe. "The model projects that a deoxygenation of the atmosphere, with atmospheric O2 dropping sharply to levels reminiscent of the Archaean Earth, will most probably be triggered before the inception of moist greenhouse conditions in Earth's climate system and before the extensive loss of surface water from the atmosphere," the team explained in their paper. At that point it'll be the end of the road for human beings and most other life forms that rely on oxygen to get through the day, so let's hope we figure out how to get off the planet at some point within the next billion years. To reach their conclusions, the researchers ran detailed models of Earth's biosphere, factoring in changes in the brightness of the Sun and the corresponding drop in carbon dioxide levels, as the gas gets broken down by increasing levels of heat. Less carbon dioxide means fewer photosynthesizing organisms such as plants, which would result in less oxygen. Scientists have previously predicted that increased radiation from the Sun would wipe ocean waters off the face of our planet within about 2 billion years, but the model here – based on an average of just under 400,000 simulations – says the reduction in oxygen is going to kill off life first. "The drop in oxygen is very, very extreme," Earth scientist Chris Reinhard, from the Georgia Institute of Technology, told New Scientist. "We're talking around a million times less oxygen than there is today." What makes the study particularly relevant to the present day is our search for habitable planets outside of the Solar System. Increasingly powerful telescopes are coming online, and scientists want to be able to know what they should be looking for in the reams of data these instruments are collecting. It's possible that we need to be hunting for other biosignatures besides oxygen to have the best chance of spotting life, the researchers say. Their study was part of the NASA NExSS (Nexus for Exoplanet System Science) project, which is investigating the habitability of planets other than our own. According to the calculations run by Ozaki and Reinhard, the oxygen-rich habitable history of Earth could end up lasting for just 20-30 percent of the planet's lifespan as a whole – and microbial life will carry on existing long after we are gone. "The atmosphere after the great deoxygenation is characterized by an elevated methane, low-levels of CO2, and no ozone layer," said Ozaki. "The Earth system will probably be a world of anaerobic life forms." The research was published in Nature Geoscience. An earlier version of this article was published in March 2021. The Ocean Is Getting Darker, Threatening All That Lives Within Your Salad Could Be Carrying Microplastics From Soil Into Your Body UN Warns: High Odds We'll Exceed 1.5°C Temp Rise by 2029
Yahoo
4 days ago
- Climate
- Yahoo
Tracking a Toasty Start to June
Wildfire smoke from Canada is still to blame for the milky looking sky. A lot of this smoke is further up in the atmosphere so is not impacting air quality at the surface. Toasty conditions will continue through sunset this evening. That 20% chance of rain is still holding strong as a small system will bring in minimal moisture. This system will be very scattered and not everyone will see rain this evening. However, those who do could have a couple of rumbles of thunder with this system. If participating in any outdoor activities this evening make sure to remember, 'When thunder roars go indoors.' Behind tonight we will remain dry Sunday and most of the day Monday as temperatures will climb to almost 90 degrees. Tuesday is when we enter a more active weather pattern. A low pressure system will bring in loads of moisture and rain chances starting late Monday night, and all day Tuesday. There is a potential that these storms are strong to severe as they enter a favorable environment to our west. As we get closer to Tuesday make sure you are keeping up to date with your Storm Tracker weather team for more information. After Tuesday rain chances will carry throughout the rest of the week and to start next weekend.
Yahoo
27-05-2025
- Climate
- Yahoo
Dry heat to torrential rain - enter the age of 'weather whiplash'
After weeks of dry, sunny conditions in Scotland, torrential downpours over the bank holiday weekend marked a sudden change in weather. Barely a drop of rain was recorded over almost the entire month. March and April were far drier than normal, with May seeing only 4% of the normal rainfall by the middle of the month. This flip between extremes has introduced a new phrase to our forecasting vocabulary - weather whiplash. And it looks likely we will have to get used to the idea that our weather will see wild swings from one extreme to another over short periods of time because of climate change. The settled spell was caused by persistent blocked weather patterns, with high pressure dominating. The jet stream - a fast-flowing current of air - helped lock high pressure in place, deflecting low pressure systems and rain elsewhere. Before the weather turned last weekend, Scotland had only recorded 41% of its usual spring rainfall, with just seven days left of the season. This switch is driven by a warming world speeding up the water cycle and allowing the atmosphere to hold more water. So when it does rain, the rain is heavier, which in turn can lead to flooding. We know that our weather will continue to become more extreme, because global temperatures are rising due to human-induced climate change. Spring is the fastest warming season in the UK across all four nations. So when the sun is out, the temperature will be higher than historical records. Blocked weather patterns are a natural part of our weather variability but they help increase the weather extremes created by a warming world. However, climate scientists are not in agreement that we'll see more blocked patterns in the future. One school of thought is that a warming Arctic makes the jet stream more "wavy", allowing high pressure to become stuck and the blocking to occur, but an increase in blocking events isn't supported by the climate models used to predict future trends. In reality, the dry spring comes as a double-edged sword. At the Cheesy Toast Shack on the East Sands of St Andrews, the dry weather has been a boon for business, with trade up 30% compared with May last year. Owner Kate Carter-Larg said: "Last spring was a little on the wet side and the weather has definitely helped this year. We've just been incredibly busy - midweek, weekends - it's just busy all the time. It's a huge factor that the weather has been so dry." But our farmers and growers have been struggling in the dry conditions. Water scarcity also prompted a plea to the public from Scottish Water, to actively think about our water usage in order to conserve reserves. Climate scientist Dr Matt Patterson from the University of St Andrews said: "With climate change we can expect that we're going to see more periods of variability in weather. "It's often been called 'weather whiplash', the idea that we have some very prolonged dry periods, but then also when it rains, it rains more heavily". One of the impacts of our warming climate is that the atmosphere holds more water. For every one degree increase in global temperature, our atmosphere holds 7% more water. As a result, the natural water cycle is sped up and intensified. The impact of climate change on our day-to-day weather is marked. The intensity of UK rainfall has increased by 15% since 1891, with an observed increase in each season, though winters are wetter than summers. Five of the ten wettest years recorded in the UK have occurred in the 21st century. Six of the UK's top-ten warmest years have occurred since 2014 and all of the top ten warmest years have occurred in the 21st century. Statistics supplied by Royal Meteorological Society and Met Office. UK sea temperatures soar after exceptionally warm spring
BBC News
27-05-2025
- Climate
- BBC News
Dry heat to torrential rain - why Scotland is experiencing 'weather whiplash'
After weeks of dry, sunny conditions in Scotland, torrential downpours over the bank holiday weekend marked a sudden change in a drop of rain was recorded over almost the entire and April were far drier than normal, with May seeing only 4% of the normal rainfall by the middle of the month. This flip between extremes has introduced a new phrase to our forecasting vocabulary - weather it looks likely we will have to get used to the idea that our weather will see wild swings from one extreme to another over short periods of time because of climate change. Pendulum of change The settled spell was caused by persistent blocked weather patterns, with high pressure jet stream - a fast-flowing current of air - helped lock high pressure in place, deflecting low pressure systems and rain the weather turned last weekend, Scotland had only recorded 41% of its usual spring rainfall, with just seven days left of the switch is driven by a warming world speeding up the water cycle and allowing the atmosphere to hold more water. So when it does rain, the rain is heavier, which in turn can lead to know that our weather will continue to become more extreme, because global temperatures are rising due to human-induced climate change. Spring is the fastest warming season in the UK across all four nations. So when the sun is out, the temperature will be higher than historical records. Blocked weather patterns are a natural part of our weather variability but they help increase the weather extremes created by a warming climate scientists are not in agreement that we'll see more blocked patterns in the future. One school of thought is that a warming Arctic makes the jet stream more "wavy", allowing high pressure to become stuck and the blocking to occur, but an increase in blocking events isn't supported by the climate models used to predict future trends. Good and bad for business In reality, the dry spring comes as a double-edged sword. At the Cheesy Toast Shack on the East Sands of St Andrews, the dry weather has been a boon for business, with trade up 30% compared with May last year. Owner Kate Carter-Larg said:"Last spring was a little on the wet side and the weather has definitely helped this year. We've just been incredibly busy - midweek, weekends - it's just busy all the time. It's a huge factor that the weather has been so dry."But our farmers and growers have been struggling in the dry conditions. Water scarcity also prompted a plea to the public from Scottish Water, to actively think about our water usage in order to conserve reserves. Climate scientist Dr Matt Patterson from the University of St Andrews said: "With climate change we can expect that we're going to see more periods of variability in weather. "It's often been called 'weather whiplash', the idea that we have some very prolonged dry periods, but then also when it rains, it rains more heavily". Warmer atmosphere holds more water One of the impacts of our warming climate is that the atmosphere holds more water. For every one degree increase in global temperature, our atmosphere holds 7% more water. As a result, the natural water cycle is sped up and intensified. The impact of climate change on our day-to-day weather is intensity of UK rainfall has increased by 15% since 1891, with an observed increase in each season, though winters are wetter than summers. Five of the ten wettest years recorded in the UK have occurred in the 21st century. Six of the UK's top-ten warmest years have occurred since 2014 and all of the top ten warmest years have occurred in the 21st supplied by Royal Meteorological Society and Met Office.
