Home Blog Page 50

“Doomsday Glacier” could be more stable than expected

0

The world’s largest ice caps may be less at risk of sudden collapse than expected, a new study finds.

The study in Science includes the simulation of the disappearance of the Thwaites Glacier from West Antarctica, one of the largest and most unstable glaciers in the world.

The researchers modeled the collapse of varying heights of ice cliffs, almost vertical formations that occur where glaciers and ice shelves meet the ocean. They discovered that instability does not always lead to rapid disintegration.

“What we found is that over long time scales, ice behaves like a viscous fluid, much like a pancake spreading out in a frying pan,” says Jeremy Bassis, associate professor at climate and space science and engineering at the University of Michigan. “So the ice is expanding and thinning faster than it can fail and that can stabilize the collapse. But if the ice can’t thin out fast enough, then you have the possibility of a rapid glacier collapse. “

Researchers combined the variables of ice breakage and ice flow for the first time, finding that stretching and thinning of ice, as well as the strengthening of trapped chunks of ice, can moderate the effects of l fracture-induced sea ice cliff instability.

Iceberg calving

The new findings add nuance to a previous theory called sea ice cliff instability, which suggests that if the height of an ice cliff reaches a certain threshold, it can suddenly disintegrate under its own weight in a chain reaction. of ice fractures.

The Thwaites Glacier in Antarctica, sometimes referred to as the “Doomsday Glacier,” is approaching this threshold and could contribute nearly 3 feet to sea level rise in the event of a complete collapse. At 74,000 square miles, it is roughly the size of Florida and is particularly sensitive to climate and ocean changes.

“The ocean is still there, tickling the ice in a very complex way, and we’ve only known for a decade or two how important that is.”

The researchers also found that icebergs that crack and fall from the main glacier in a process known as “iceberg calving” can actually prevent, rather than contribute to, catastrophic collapse. If the chunks of ice get stuck on outcrops on the ocean floor, they can put back pressure on the glacier to help stabilize it.

Bassis notes that even if the glacier does not collapse catastrophically, the exposure of a high cliff could still trigger a retreat of a few kilometers per year, or the length of about 20 football fields, which would result in a important contribution to future sea level rise.

The complete collapse of the Thwaites Glacier?

While it is clear that Thwaites and other glaciers are melting, the speed of their disappearance is of great interest to coastal areas as they develop strategies to adapt and build resilience.

But predicting the retreat of glaciers is an incredibly complex endeavor, as they are affected by the interplay of a myriad of factors – the stress and strain of billions of tons of moving ice, changes in air temperature and of water, and the effects of liquid flow. water on ice, to name a few.

As a result, predictions of the collapse of the Thwaites Glacier range from a few decades to several centuries. The new study, says Bassis, is an important step towards producing accurate and actionable predictions.

“There is no doubt that sea levels are rising and that this will continue for the next several decades,” says Bassis. “But I think this study offers hope that we are not approaching a complete collapse, that there are measures that can ease and stabilize things. And we always have the opportunity to make a difference by making decisions about things like energy emissions – methane and CO.2. “

The fate of the Antarctic and Greenland ice caps

The study results will also be useful in predicting the fate of other glaciers and ice formations in the Arctic and Antarctic, says Anna Crawford of the University of St. Andrews.

“This important information will inform future research on the retreat of the Thwaites Glacier and other large outlet glaciers from the West Antarctic ice sheet that are likely to retreat due to the breaking of ice cliffs and instability. sea ​​ice cliffs, ”she said. “They highlight the conditions that facilitate recoil, demonstrate the terminal’s stabilizing potential, and show how sea ice can actually slow down the collapse process.”

The research team is already working to further refine their models by incorporating additional variables that affect glacial retreat, including how the shapes of individual glaciers affect their stability and the interaction between glacial ice and the liquid ocean that l ‘surrounds, explains Bassis.

“The ocean is still there, sort of tickling the ice in a very complex way, and we’ve only known for a decade or two how important that is,” he says. “But we’re starting to understand that this is the root of a lot of the changes we’re seeing, and I think this will be the next big frontier in our research.”

Additional researchers from the University of Michigan and the University of St. Andrews contributed to the work.

The study is part of the International Thwaites Glacier Collaboration. The DOMINOS project, a component of the International Thwaites Glacier Collaboration, the National Science Foundation and the Natural Environment Research Council funded the work.

Source: University of Michigan


Source link

China and Russia team up for space race with the United States

0

Luna 27 and Chang’e-6, for example, are expected to drill the surface and return samples to Earth – a feat China already accomplished last December with Chang’e-5 and the Soviet Union with the three-way Luna landers. times in the 1970s. In a second stage, between 2026 and 2030, the Chang’e-8 and Luna 28 missions will land separately with the first constituent elements of the new station.

The first of the Russian missions is scheduled for October, although the Russian space program has experienced long delays.

Ultimately, China hopes the station will demonstrate its ability to develop water, mineral and energy resources that could enable the short-term survival of astronauts and serve as a basis for deeper space exploration.

“A permanent base has both symbolic and power projection capabilities,” said Namrata Goswami, independent analyst and co-author of a new book on space exploration, “Scramble for the Skies.”

NASA has its own plans to send astronauts back to the moon – and one day send them to Mars – and has recruited partners under a deal, called the agreements of Artemis, governing space activities, including operations, experiments and the extraction of natural resources.

China is not explicitly excluded but seems almost certain not to sign, given US restrictions on space cooperation and its own determination to build an indigenous program. Russia, too, seems unlikely to sign, given its tilt towards China.

As Dr Johnson-Freese of the United States Naval War College said, “China is keeping Russia in the space game to a much greater extent than the Russian economy would otherwise support.”

Andrew E. Kramer reported from Moscow, and Steven Lee Myers from Seoul. Claire Fu in Beijing and Oleg Matsnev in Moscow contributed to the research.


Source link

Methane on Enceladus: a possible sign of life?

0
View of the moon Enceladus from Saturn via the Cassini probe. A new study by a group of biologists shows that something produces a lot of methane in the moon’s underground ocean. Could this be life? Image via NASA / ESA / JPL / SSI / Cassini Imaging Team / Carnegie Science.

With its global ocean of groundwater, Saturn’s moon Enceladus is considered one of the best places to seek life. Now, new research from a team of biologists suggests that life on Enceladus may indeed be entirely possible … and that we strength already have evidence for this. Something is producing a lot of methane on Enceladus, or rather in its underground ocean. And methane can be a sign of life. Charlie wood discussed these curious results on June 8, 2021, Popular science. Oddly, according to Wood’s article, the initial analysis suggests that methane is produced in a manner similar to methanogen microbes in Earth’s oceans.

It is not yet proof of life on, or rather in, Enceladus, but it is certainly interesting.

the Peer reviewed the conclusions were published June 8, 2021 at Nature astronomy.

Methane in Enceladus: hydrothermal vents and methanogens

The original detection of methane comes from the analysis of data obtained by the Cassini spatialship. The probe made several close flights of the moon. At one point, it passed through plumes of water vapor bursting through cracks at the south pole of Enceladus. The water vapor in the plumes originates from the ocean deep below the icy outer surface.

Additionally, Cassini found particles of ice, salts, hydrogen, and organic molecules in the plumes, provisional clues to an ocean similar in composition to Earth’s oceans. There is also evidence of hydrothermal vents on the Enceladus seabed, similar to those that support methanogens in Earth’s oceans. As stated in the article summary:

Observations from NASA’s Cassini spacecraft have established that Saturn’s moon Enceladus has an internal liquid ocean. Analysis of a plume of oceanic material ejected into space suggests that alkaline hydrothermal vents are present on the seabed of Enceladus. On Earth, such underwater vents harbor microbial ecosystems rich in methanogenic archaea.

Planet with a large slice revealing a gray core surrounded by a thick blue layer with many small geysers at the bottom.
Cutaway view of the interior of Enceladus, showing the underground ocean and jets of water vapor erupting through cracks in the icy surface of the South Pole. Image via Popular science.

So what is it that produces methane on Enceladus?

Scientists already knew methane existed, but the new study shows that its surprisingly high amount is difficult to explain. Basically the most likely chemical process that could produce methane on Enceladus, serpentinization, would not be able to create as much as what is observed. So what could? As Antonin Affholder, at ENS Paris and main author, confided Popular science:

Methanogens are able to explain the amount of methane.

Curved edge of a cracked, cratered moon with very large geysers erupting in space.
The geysers of the moon Enceladus of Saturn. These enormous plumes of water vapor erupt through the cracks of the South Pole of Enceladus. The Cassini spacecraft analyzed the plumes, finding water vapor, ice particles, salts, methane, and a variety of complex organic molecules. Scientists believe the plumes originate from a global ocean below the moon’s icy surface. Image via Nasa.

Methanogens are microbial life forms that eat hydrogen and carbon dioxide and produce methane as a by-product. On Earth, they are found in deep-water hydrothermal vents like those thought to exist on the seabed of Enceladus.

So, could this really be the explanation for the methane on Enceladus?

Organic or non-organic?

With this in mind, the researchers considered all possible scenarios where methane could be produced in the Enceladus Ocean. In serpentization, the interaction of hot water and minerals in rocks can create hydrogen. Subsequently, chemical reactions can then combine hydrogen and carbon dioxide to produce methane.

It seemed plausible, so the researchers took a closer look at the possibility. They wanted to see how much methane could realistically be produced on Enceladus. They then compared these results, using Bayesian analysis, to a scenario where methanogens were involved. In fact, the researchers used real organisms on Earth for the comparison. Overall, it was important to keep their expectations realistic, as Affholder explains:

We cannot just imagine what we want to imagine. We need to base our assumptions on what we know.

Young smiling man with glasses, short beard and messy hair.
Antonin Affolder at the ENS in Paris led new research into the mystery of Enceladus methane. Image via ENS.

“Too much” methane

The results were surprising: the amount of methane detected by Cassini was significantly higher than what could be easily explained by serpentization alone. Affholder said:

The first hypothesis is totally disqualified, score of zero.

As stated in the summary, there was apparently “too much” of methane to be easily explained by inorganic chemistry alone. Extract from the summary:

Here, we use a Bayesian statistical approach to quantify the probability that methanogenesis (production of biotic methane) can explain the escape rates of molecular hydrogen and methane in the Enceladus plume, as measured by Cassini instruments.

We note that the observed escape rates (1) cannot be explained solely by the abiotic alteration of the rock core by serpentinization; (2) are compatible with the assumption of habitable conditions for methanogens; and (3) mark the highest probability under the methanogenesis hypothesis, assuming that the probability of emergence of life is high enough.

Too much hydrogen?

In addition, Cassini also found an abundance of hydrogen in the ocean, which could be used as a food source for microbes. But, it seemed that there was more of it left than there should be if it was consumed as food. Ultimately, there could also be an answer to this mystery. It is believed that most of the hydrogen molecules are very close to the vents, where it would be too hot for the methanogens. Instead, organisms could feast on hydrogen molecules farther away from the vents. In this scenario, there would be little impact on the overall abundance of hydrogen.

Ocean floor with insets showing hydrothermal features that could release methane over Enceladus.
Sectional view of the underground ocean of Enceladus. There is evidence of hydrothermal vents on the ocean floor, just like on Earth. Could methane come from methanogenic microbes? Image via Nasa/ JPL-Caltech / SwRI.

More data needed

Serpentization, at least on its own, seems like an unlikely solution to the methane mystery. It is always possible that there is an excess of primordial methane, left over from the formation of Enceladus, bubbling from its core. Or another still unknown process at work. As Affholder points out, we still don’t know enough about Enceladus to be sure:

We do not know the origin of Enceladus. We do not know the age of Enceladus. We do not know the precise nature of methane. To find out more, we might need a mission to examine methane.

In short, answering these questions will require more data. Unfortunately, no return mission is planned at this time. Cassini analyzed the plumes in detail, but it goes without saying that a probe that could specifically look for evidence of life itself in them would be even better. Here’s hoping!

Conclusion: something produces a lot of methane in the ocean of Enceladus. Could this be life? Although not yet proven, a new study by a team of biologists appears to support this exciting possibility.

Source: Bayesian analysis of data from the Enceladus plume to assess methanogenesis

Via popular science


Source link

The Antarctic glacier may be more stable than initially feared

0
Ice cliff – credit Rob Larter, British Antarctic Survey

New international study sheds light on the future of the massive Thwaites Glacier and other ice caps.

The world’s largest ice caps may be at less risk of sudden collapse than expected, according to new findings led by the University of Michigan, in partnership with the University of St Andrews as part of the International Thwaites Glacier Collaboration.

The team of international researchers simulated the disappearance of one of the world’s largest and most unstable glaciers, the Thwaites Glacier in West Antarctica. The team of scientists modeled the collapse of varying heights of ice cliffs, almost vertical formations that occur where glaciers and ice shelves meet the ocean, and found that instability does not always lead to rapid disintegration.

The Thwaites Glacier covers 192,000 square kilometers (74,000 square miles), the size of the US state of Florida or Great Britain, and is particularly sensitive to climate change.

Over the past 30 years, the overall rate of ice loss from Thwaites and its neighboring glaciers has more than quintupled. Already, the ice flowing from Thwaites into the Amundsen Sea accounts for about four percent of global sea level rise. A precipitous collapse of the glacier could cause a significant rise in sea level of about 65 cm (25 inches) and scientists want to know if or when this could happen.

The new findings, published in Science (Friday, June 18, 2021), add a nuance to a previous theory called sea ice cliff instability, which suggested that if the height of an ice cliff reaches a certain threshold, it may suddenly disintegrate under its own weight in a chain reaction of ice fractures. The Thwaites Glacier in Antarctica, sometimes referred to as the “Doomsday Glacier”, is approaching this threshold.

Researchers combined for the first time the variables of ice breakage and ice flow, finding that stretching and thinning of ice, as well as strengthening of trapped chunks of ice, can moderate the effects of l instability of the sea ice cliff induced by the fracture.

Principal Investigator, Associate Professor Jeremy Bassis, University of Michigan, said: “What we found is that over long time scales, ice behaves like a viscous fluid, kind of like a pancake spreading out in a frying pan. Thus, the ice spreads and thins faster than it can break, which can stabilize the collapse. But if the ice can’t thin out fast enough, then you have the possibility of a rapid glacier collapse. “

Ship the Nathaniel B Palmer to Thwaites Glacier credit Alex Mazur

The research team also found that icebergs that crack and fall from the main glacier during a process known as “iceberg calving” can prevent, rather than contribute to, catastrophic collapse. If the chunks of ice get stuck on outcrops on the ocean floor, they can put back pressure on the glacier to help stabilize it.

But Bassis notes that even if the glacier does not collapse catastrophically, the exposure of a high cliff could still trigger a retreat of a few kilometers per year, or the equivalent of the length of about 20 lots. football and resulting in a significant contribution to future sea level rise.

While it is clear that Thwaites and other glaciers are melting, the speed of their disappearance is of great interest to coastal areas as they develop strategies to adapt and build resilience. But predicting the retreat of glaciers is an incredibly complex matter, as they are affected by the interplay of many factors: the stress and strain of billions of tons of moving ice, changes in air and temperature. water and the effects of liquid water flowing over ice, to name a few. As a result, predictions of the collapse of the Thwaites Glacier range from a few decades to several centuries. The new study is an important step towards producing accurate and actionable predictions.

Bassis explains: “There is no doubt that sea levels are rising, and that this will continue for decades to come. But I think this study offers hope that we’re not approaching a complete collapse – that there are measures that can ease and stabilize things. And we can always make a difference by making decisions about things like energy emissions, methane, and CO2.

The article’s co-author, Dr Anna Crawford, of the School of Geography and Sustainable Development at the University of St Andrews, added that the results of the study will also be useful in predicting the fate of other glaciers and ice formations in the Arctic and Antarctic: “This important information will inform future research on the retreat of the Thwaites Glacier and other large outlet glaciers from the West Antarctic ice sheet that are vulnerable to retreat by rupture of ice cliffs and instability of sea ice cliffs.

“They highlight the conditions that facilitate recoil, demonstrate the potential for restabilization of the terminal, and show how sea ice can actually slow down the collapse process.”

The research team is already working to further refine their models by incorporating additional variables that affect glacial retreat, including how the shape of individual glaciers affects their stability and the interaction between glacial ice and the liquid ocean that l ‘surrounded.

Bassis adds: “The ocean is still there, sort of tickling the ice in a very complex way, and we’ve only known for a decade or two how important it is, but we’re starting to understand. that this is driving a lot of the changes we’re seeing, and I think this will be the next big frontier in our research.


The article Transition to Marine Ice Cliff Instability Controlled by Ice Thickness Gradients and Velocity by JN Bassis, B. Berg, AJ Crawford and D. Benn is published in the journal Science.

Please ensure that the article’s DOI 10.1126 / science.abf6271 is included in all online stories and social media posts and that Science is credited as the source.

This study is part of the International Thwaites Glacier Collaboration, one of the objectives of which is to provide critical observations of the past and present behavior of Thwaites in order to better test the models and predict with more certainty the future fate of the glacier.

The research was supported by the DOMINOS project, a component of the International Thwaites Glacier Collaboration, and by the National Science Foundation (grant number 1738896) and the Natural Environment Research Council (grant number NE / S006605 / 1).

The International Thwaites Glacier Collaboration (ITGC) is a five-year, joint US and UK $ 50 million mission to learn more about Thwaites Glacier, its past and what the future holds. Significant research contributions also come from Sweden, Germany and South Korea. The ultimate goal of the project is to predict to what extent Thwaites will contribute to global sea level rise and how soon a transition to faster ice retreat could occur. ITGC is funded by the National Science Foundation (NSF) of the United States and the Natural Environment Research Council (NERC) of the United Kingdom.

Pack ice is a large floating shelf of ice that forms where a glacier or ice cap flows to a shoreline and across the ocean surface. Ice shelves are found only in Antarctica, Greenland, Canada and the Russian Arctic.

The ice cap, also known as the continental glacier, is a mass of glacial ice that covers the surrounding terrain and measures over 50,000 km2 (19,000 square miles).

The glacier is a huge mass of ice that moves slowly across the land. The term “glacier” comes from the French word glace (glah-SAY), which means ice. Glaciers are often called “rivers of ice”.

/ Public distribution. This material is from the original organization and may be ad hoc in nature, edited for clarity, style and length. See it in full here.


Source link

Scientist who led largest Arctic mission says global warming may have reached irreversible tipping point

0

The scientist who led the largest research expedition ever to the Arctic has suggested that the tipping point of irreversible global warming may already be reached.

Dr Markus Rex, an atmospheric physicist, made the comments earlier this week as he presented the first results of the North Pole expedition that involved 442 experts from 20 countries.

“The disappearance of summer ice in the Arctic is one of the first landmines in this minefield, one of the tipping points we first trigger when we push warming too far,” said Dr Rex. AFP.

“And one can basically wonder if we haven’t already walked on this mine and already triggered the start of the explosion.”

The Multidisciplinary Drifting Observatory for the Study of the Arctic Climate – or “MOSAiC” expedition – lasted 389 days and collected data on the atmosphere, ocean, sea ice and ecosystems. The objective was to assess the impact of the climate crisis on the Arctic region and more generally on the world.

Among the first findings, Dr Rex said the team found that the Arctic sea ice had retreated “faster in the spring of 2020 than since the records began” and that “the spread of sea ice in summer was not than half the size of decades “. since”.

He added: “Only evaluation over the next few years will allow us to determine whether we can still save the Arctic sea ice year round through vigorous climate protection or whether we have already passed this important tipping point in the system. climate.

Man-made global warming is warming the world’s oceans and increasing the rate of melting of Arctic sea ice. White ice will reflect sunlight, so when the dark ocean is exposed, it will absorb even more sunlight, causing more heating.

In the summer of 2020, the ice in the Arctic Ocean melted to its second lowest level on record, according to US scientists, due to a combination of global warming and natural forces.

The extent of the ice-covered ocean at the North Pole and extending further south to Alaska, Canada, Greenland and Russia hit a summer low of 1.4 million square miles last September. Arctic sea ice reaches its lowest point in September and its maximum in March.

He was only a finalist in 2012 when the ice shrank to 1.3 million m² (3.4 million km²), according to the National Snow and Ice Data Center, which has kept satellite records since 1979.

In the 1980s, ice cover was approximately 1 million m² (2.7 million km2) greater than current summer levels.

Last year scientists said The independent who claims the world is “doomed” can be detrimental to global efforts to tackle the climate crisis, and that it was important to understand that it was not too late to act.

Leo Barasi, author of Climate Majority, said: “Claims that the world is irreversibly doomed to uncontrollable warming, and no reduction in emissions can help us, can still find an audience, as can claims that change climate has nothing to fear. But these claims are usually based on studies or outlier data that have been taken out of context and ignore all evidence to the contrary.

“Telling the world that we are doomed, when it is not supported by evidence, is irresponsible and unlikely to motivate the urgent action that can still prevent disastrous warming. “

AP contributed to this report


Source link

Competitors compete for Army Arctic vehicle contract

0

Competitors vie for arctic army vehicle contract

Beowulf

BAE Photo Systems

The Army prepares for the harsh conditions of the harsh Arctic as it pursues a new cold-weather vehicle. The service is ramping up testing as it strives to select the manufacturer for its next-generation platform.

The Army Small Unit Support Vehicle, or SUSV, was last purchased in 1983 to help soldiers navigate difficult terrain such as snow, mud, and swamps. The platform, which is amphibious and tracked, has a footprint that exerts less pressure than a human foot, allowing it to traverse deep snow smoothly.

A year after the competition for the system replacement began, two manufacturers – BAE Systems and Oshkosh Defense – are competing in hopes of winning a contract for the cold weather all-terrain vehicle program. Each contractor was expected to produce two prototypes by June, with testing and evaluation ongoing until the end of the year.

BAE Systems – the incumbent – was selected in April by the National Advanced Mobility Consortium to provide prototypes for military review. Its offering, the Beowulf, is an unarmoured version of its BvS10 platform, an amphibious vehicle that has already been manufactured for the military in five countries: Sweden, Norway, UK, Austria and France.

The Swedish military recently ordered 127 additional vehicles, adding to the nearly 10,000 vehicles already in service internationally.

The Beowulf would be a proven choice for the military, said Mark Signorelli, vice president of business development for BAE’s platforms and services division.

“This is a vehicle that has literally millions of miles of history in its legacy vehicles, in its sister vehicles in arctic conditions, and I can’t imagine there is better for the needs of the world. army than what Beowulf can provide, ”he said. said on a call with reporters.

According to the Pentagon’s budget documents, future CATV platforms would have the capacity to traverse “a wide range of otherwise impassable terrain” all year round. This includes frozen ice and extremely cold weather conditions to support training. The military announced earlier this year that the service will build a combat training center in Alaska to bolster its defense in the arctic.

BAE Systems has tested the BvS10 in the Arctic, in hot-weather peatlands and other difficult conditions such as upwelling rivers in Afghanistan, Signorelli said.

According to the program requirements, the next-generation vehicle should be able to float with “sufficient freeboard to operate with one foot waves”. It must also be able to swim at a minimum speed of two knots with “little or no” change in vehicle configuration.

“Because of this flotation ability, even in the worst bogs, mud and swamps, you can move around without getting stuck,” Signorelli said of the Beowulf’s capabilities.

Sharing common parts with the BvS10, such as the suspension and drivetrain, would allow the service to keep routine maintenance and maintenance costs low, he added. Signorelli noted that the Beowulf production site in Örnsköldsvik, Sweden, is roughly the same distance from the North Pole as the test site in Yellowknife, Alaska. Moving production to the United States would not be profitable given the rapidly approaching delivery schedule, he added.

Signorelli declined to give the value of the other transaction authorization agreement the company received for the prototyping phase.

He noted that because testing was delayed by a winter cycle due to a delay in funding the military, the Örnsköldsvik facility had more time to anticipate production hurdles.

“The team has been preparing for some time to move into production of this product,… so we believe these challenges have been identified and mitigated,” he said.

Meanwhile, Oshkosh and its partner Singapore Technologies Engineering are also preparing their bid for the program, said Pat Williams, vice president of Oshkosh Defense and general manager of U.S. Army and Marine Corps programs.

The system is based on ST Engineering’s Bronco 3 platform, which is part of its Bronco family of vehicles that have undergone more than 1,860 miles of performance testing in arctic conditions as well as over 200,000 miles in terrain. difficult desert, according to Oshkosh.

After the vehicle is delivered, competitors will have to go through the military’s rigorous testing process until a selection to a company is made in 2022, a test for which Williams says Oshkosh is ready.

“The big ‘aha’ that happened in the middle of it all was the launch of the Army’s ‘Regaining Arctic Dominance’ strategy,” Williams said.

The strategy – the service’s first to focus on the region – was released in March. He presented plans to establish a two-star headquarters with specially trained and equipped combat brigades; improving the readiness of materiel for extended operations; better train regional forces; and improve the quality of life for military personnel.

Williams said his team had spent “a lot of time” going through the 54-page document to better understand how the service will approach its competitors close to the region.

“[We’re] making sure that what we offer really meets those goals, ”he said.

For example, the strategy highlighted the obstacles the Army faces in achieving greater mobility in its operations.

“Summer poses significant challenges for many wheeled vehicles, while the most difficult period is the spring thaw, when ground movement becomes impossible over large areas of land,” according to the document.

The Bronco 3 variant offers additional payload capacity and long range for maximum efficiency, Williams said.

The vehicle is also designed to have low ground pressure, which increases mobility in swampy areas.

Oshkosh also looked at how to better accommodate soldiers, Williams noted.

The vehicle, which is built with a roomy, temperature-controlled interior for the troops, will help set the prototype apart from the competition, he said. Because the designers didn’t want soldiers to be exposed to the elements for long periods of time, the Bronco 3 is able to transform into different variants without decoupling the front from the rear of the vehicle, saving time.

“Anyone who’s lived up north and had to get gas in the winter knows it’s no fun stopping for gas when it’s freezing,” he said.

The platform will be transformed into four variants for different missions: general troop transport, freight, emergency transport and command and control, according to the budget documents. The command and control arrangement will provide the space, weight and power to accommodate standard joint communications and common image exploitation platforms.

“We really focused on the soldier in terms of vehicle capacity, but also in terms of space inside the vehicle and where your gear is stored,” Williams said.

The prototype will be tested in summer conditions in the coming months to measure performance in conditions where snow is not the predominant feature of the landscape. When the weather is cold enough in Alaska, assessments of winter conditions will begin.

Williams said the assessment will assess payload mobility, swimming ability and vehicle dynamics, among other requirements-based capabilities.

Tests of the platform over the past year have proven that it can handle military missions, he said. Although the Bronco family of vehicles have primarily been used in desert conditions, this is not a concern for him, he said.

“The soldiers took this thing into combat, they lived there, they worked there, they operated in austere environments,” he said.

Oshkosh incorporated their comments into his new design.

Meanwhile, the need for new capabilities for the Arctic region has increased.

Liselotte Odgaard, visiting principal researcher at the Hudson Institute, said almost all countries, at the last Arctic Council ministerial meeting in May, expressed interest in keeping the region in an area of ​​”low tension. “.

Although many developed countries have neglected military operations in the Arctic, most leaders can no longer ignore the advantages that Russia is trying to develop, she said. For example, it has developed a base where it can maintain missiles and accommodate bombers.

“They have all the equipment they need to dominate the region,” she said.

The fact that the military purchases vehicles for the basic function of mobility and movement of troops shows how far behind the United States in the arctic warfare is, she said.

“It’s just about being able to move personnel and equipment,” she said. “It just tells you that we’re starting from a pretty low baseline because it’s fundamental.”

She acknowledged that it is difficult for the United States to strengthen its power in the Arctic when the Indo-Pacific region receives so much attention, but said that Russia is emphasizing its geographic advantage.

“Communication between the Arctic countries is really full of huge, big holes,” she said. “The Russians know this. That is why they are constantly in the [gap] test how we react.

However, the military wants to put its money where its mouth is by prioritizing funding related to the Arctic. Although many programs have seen cuts in purchases in the Biden administration’s fiscal year 2022 budget proposal for the military, funding for the new platform has increased by more than $ 7 million. The request asks for $ 16 million to finance the purchase of 10 vehicles, up from $ 9.25 million adopted in fiscal 2021.

Acquiring equipment like the cold weather all-terrain vehicle will allow the military to train troops more effectively, Odgaard said.

The new vehicles are also sending a long-awaited signal to Russia, which has become accustomed to being the dominant force in the region, she noted.

“It is absolutely necessary to show Russia that the other Arctic nations are out there and that they are ready to defend themselves,” she said.

The subjects: Wheeled Tactical Vehicles, Army News


Source link

Massive Hudson Bay Icebergs Traveled to Florida, Research Finds

0

TORONTO – Researchers in the United States have discovered what they believe is evidence suggesting once massive icebergs were floating from northern Canada to southern Florida.

Using high-resolution seabed mapping, researchers at the Woods Hole Oceanographic Institution (WHOI) and the United States Geological Survey (USGS) have discovered around 700 iceberg erosions – a term referring to ” plow ‘on the ocean floor from icebergs. that range from North Carolina to the Florida Keys.

“The idea that icebergs can reach Florida is incredible,” Alan Condron, OMSI climate modeler. said in a press release. “The occurrence of scours at such low latitudes is very unexpected, not only because of the unusually high melt rates in this region, but also because the scours are found under the northward flowing Gulf Stream.”

The research, published Thursday in the journal Nature Communications, state that the icebergs were about 300 meters thick. They made the 5,000-plus-kilometer journey around 31,000 years ago during a period known as the Heinrich Event 3, which is already known for massive iceberg discharges.

“We also expect that there will be characteristics of younger and older scourings that result from other discharge events, given that there are hundreds of scours left to sample,” Jenna Hill said. , USGS research geologist.

Given the high ocean water temperatures near the southern states and the natural flow of the Gulf Stream in the opposite direction of iceberg movement, researchers believe the only way for the iceberg to get this far is before the melt is “massive, but short-lived glacial meltwater flow from Hudson Bay.”

“What our model suggests is that these icebergs get caught in currents created by glacial meltwater and essentially navigate along the coast,” Condron said. “When a large glacial lake dam breaks and releases huge amounts of fresh water into the ocean, there is enough water to create these strong coastal currents that essentially move the icebergs in the opposite direction to the Gulf. Stream. “

The researchers also note that these icebergs are essential in controlling the amount of warmer water transported from the southern United States to Europe via the Gulf Stream.

“As we are able to create more detailed computer models, we can actually get more precise characteristics of how the ocean actually flows, how currents move, how they separate and how they rotate.” Hill said. “It actually makes a big difference in terms of the circulation of fresh water and the actual impact on the climate.”

Long-term study of Himalayan glaciers – sciencedaily

0

The glaciers of Nanga Parbat, one of the highest mountains in the world, have shrunk slightly but steadily since the 1930s. This loss of area is evidenced by a long-term study conducted by researchers at the South Asia Institute of l ‘University of Heidelberg. Geographers combined historical photographs, surveys, and topographic maps with current data, allowing them to show glacial changes in this northwestern Himalayan massif as early as the mid-1800s.

Detailed long-term glacier studies that extend the observation period to the period preceding the ubiquitous availability of satellite data are hardly possible in the Himalayan region due to the lack of historical data. As Professor Dr Marcus Nüsser of the Institute of South Asia explains, this is not the case for the Nanga Parbat massif. The earliest documents include sketches and drawings made during a research expedition in 1856. Based on this historical data, Heidelberg researchers reconstructed glacial changes along the southern face of Nanga Parbat. Additionally, there are numerous photographs and topographic maps from rock climbing and scientific expeditions since 1934. Some of these historical photographs were taken in the 1990s and 2010s from identical vantage points for comparison. Satellite images from the 1960s supplemented the database used by Professor Nüsser and his team to create multimedia temporal analysis and quantify changes in glaciers.

The glaciers of Nanga Parbat, fed largely by avalanches of ice and snow, show significantly lower rates of retreat than in other Himalayan regions. One exception is the predominantly snow-covered Rupal Glacier, which has a significantly higher rate of retreat. “Overall, further studies are needed to better understand the particular influence of avalanche activity on glacier dynamics in this extreme high mountain region,” says Professor Nüsser.

Researchers are particularly interested in fluctuations in glaciers, changes in ice volume and the increase in debris-covered areas on the surface of glaciers. Their analyzes covered 63 glaciers already documented in 1934. “Analyzes showed that the area covered with ice has shrunk by about seven percent, and three glaciers have completely disappeared. At the same time, we have identified a significant increase in coverage. debris, ”adds Professor Nüsser. The geographical location of the Nanga Parbat massif in the extreme northwest of the Himalayan arc near the Karakorum range could play a particular role in the relatively moderate retreat of the glaciers. In the phenomenon known as the Karakorum anomaly, no significant glacier retreat has been identified as a result of climate change in this mountain range, unlike anywhere else in the world. “An increase in precipitation at high altitudes may be the reason, but the exact causes are still unknown,” says Professor Nüsser. The researchers speculate that the low ice loss in the Karakorum and Nanga Parbat region may also be due to the protection offered by the massive debris cover and year-round avalanche flow from the steep flanks.

Source of the story:

Materials provided by University of Heidelberg. Note: Content can be changed for style and length.


Source link

Antarctic soils appear to contain no life, unprecedented find

0

For the first time, scientists have discovered soils on the Earth’s surface that appear to harbor no life. The soils originated from two windswept rocky ridges in the interior of Antarctica, 300 miles from the South Pole, where mountains cut through ice several thousand feet thick.

“The assumption has always been that microbes are resistant, they can live anywhere,” says Noah Fierer, a microbial ecologist at the University of Colorado, Boulder, whose team has studied soils. After all, single-celled organisms have been found living in hydrothermal vents above 93 degrees Celsius, living in lakes trapped under half a mile of ice in Antarctica, and even surviving at an elevation of 120,000 feet in the Earth’s stratosphere. . But after a year of testing, Fierer and his doctoral student Nicholas Dragone still haven’t found any signs of life in some of the Antarctic soils they have collected.

Fierer and Dragone studied the soils of 11 different mountains, representing a wide range of conditions. Those from the lower, less freezing mountains contained bacteria and fungi; but in some of those of the two higher, drier and colder mountains, no sign of life moved.

“We can’t say they’re sterile,” says Fierer. Microbiologists are used to finding millions of cells in a teaspoon of soil; so a tiny number, say 100 living cells, could potentially escape detection. “But as far as we can tell, they do not harbor any microbial life.”

Looking for signs of life

Whether some of the soils are truly lifeless, or later turn out to harbor a few surviving cells, this new finding, recently published in the journal JGR Biogeosciences– could help guide efforts to find life on Mars. The soils of Antarctica are perpetually frozen, saturated with toxic salts, and have not tasted appreciable amounts of liquid water for up to two million years, like Martian soils.

They were collected during a January 2018 expedition, funded by the National Science Foundation of the United States, to a remote part of the Transantarctic Mountains. These cross the interior of the continent, separating the high polar shelf in the east from the low sea ice in the west. Scientists camped on Shackleton Glacier, a 60-mile-long ice conveyor belt that pours through a gap in the mountains. They used a helicopter to reach the heights and collect samples from top to bottom of the glacier.

On the warmer, wetter mountains at the foot of the glacier, a few hundred feet above sea level, they found soils inhabited by animals smaller than sesame seeds: microscopic worms, tardigrade eight legs, whiskered rotifers and wingless insects called springtails. These sandy, bare soils were home to less than a thousandth of the number of bacteria you would find in a well-manicured lawn, just enough to provide food for the tiny grazing beasts that lurk beneath the surface.

But as the team visited higher mountains higher up on the glacier, those signs of life gradually diminished. At the upper end of the glacier, they visited two mountains – Schroeder Hill and Roberts Massif – which rise over 7,000 feet above sea level.

The visit to Schroeder Hill was brutal, recalls Byron Adams, a biologist at Brigham Young University in Provo, Utah, who led the project. The temperature on that summer day was close to -17 ° C. Howling winds – which slowly evaporate the snow and ice, keeping the mountains bare – constantly threatened to lift and throw the garden shovel they had brought to dig in the sand. The ground was strewn with reddish volcanic rocks, pitted and polished by eons of wind scouring.

As scientists lifted rocks, they found their undersides covered with white salts, toxic crystals of perchlorates, chlorates and nitrates. Perchlorates and chlorates are caustic reactive salts used in rocket fuels and industrial bleaches, and also abundant on the surface of Mars. Salts had accumulated on these parched Antarctic mountains because there was no water to wash them off.

“It was like sampling on Mars,” Adams says. When you dig in the shovel, “you know you’ve been the first thing to disturb this soil for ages, maybe millions of years.”

The researchers speculated that even in these highest and harshest places, they would still find a few living microbes crouching in the ground. But that expectation began to crumble in late 2018, as Dragone used a method called polymerase chain reaction (PCR) to detect microbial DNA in dirt. Dragone tested 204 mountain samples along the glacier. Those from the lower, less icy mountains produced abundant DNA; but a large portion of the samples from the higher elevations (20%), including most of those from Schroeder Hill and the Roberts Range, yielded absolutely nothing, suggesting they contained very few microbes or perhaps be none.

“When he started showing me some of the results, I thought to myself:”Something‘is wrong’, says Fierer. He thought there must be a problem with the samples or the lab equipment.

Dragone continued with a battery of additional experiments looking for signs of life. He incubated the soils with glucose, to see if something living in the soil converted it to carbon dioxide. He tried to detect a chemical called ATP, which all life on Earth uses to store energy. And for months, he incubated chunks of soil in a variety of nutrient cocktails, trying to coax any microbes there to grow into colonies.


Source link

Alternatives to Payday Loans in Maryland

0

As one of the easiest methods to get a quick cash advance, payday loans are widely offered to the public. The exceptions are the states where specific regulations regarding these loans are applied.

Such a situation is currently inconvenient for the residents of Maryland. Yet with some quality advice from Cash Loans Near Me in Ohio, you can make the most of the options available. We will walk you through the payday loan alternatives available in the state of Maryland.

In addition, we do our best to guide you through all the alternatives so that you have an easier time getting loans. If you live in Maryland, we’ve got some great news for you; although payday loans are prohibited, loan interest rates are low.

So, one of the solutions on payday loan alternatives in Maryland should easily cover your loan needs!

Types of Payday Loan Alternatives in Maryland

As stated by Maryland law, advance lenders must be approved by the Financial Regulation Commissioner. Thus, all existing service providers have to accept the extremely low interest rates.

Perhaps it may even be of benefit to the Maryland public that advance loans are so carefully regulated. Without further ado, let’s now focus on the different types of payday loan alternatives available in Maryland.

Short term loan alternative

A short term loan from Maryland financial institutions is among the closest things to payday loans to be found. Once in the government program, the user can take advantage of the advanced loan schemes established in Maryland.

Even payment extensions can be implemented in coordination with a financial expert. It is quite easy for you to find short term loans in Maryland which differ from payday loan services.

Prepaid debit card loans

Another aspect that may be of interest to you in terms of payday loan alternatives is the prepaid card loan. In essence, you can set up specific rules with the lender on how to deposit on the prepaid card. The funds received can be used freely with a personal PIN code given to the user.

However, while this option is quite effective, it still borders on payday loan services. So be careful with this type of offer in Maryland.

Installment Loans in Maryland

One of the simplest and most legitimate means of financial loans in Maryland is the installment loan. As much as these loans are subject to certain rules, their return mechanism makes them attractive for one of the payday loan alternatives.

The lender will agree with you based on the proposed period for the return of funds. In some cases even extensions are possible, but beware of increased interest rates in such cases.

Maryland Government Programs

As much as this option is not among the conventional payday loan alternatives, it can be very effective. Namely, residents of Maryland can participate in various government programs and avoid needing a payday loan.

Government training programs can help you start your business, while support programs overlap. Family support is one of the main government programs and is to help low income families.

This form of short term loan is much more convenient to use than traditional payday loans with high interest rates.

Conclusion

Essentially, the recommended payday loan alternatives listed are not that different from the payday loan itself. Some of the methods also include interest rates offered by the government, but with lower terms.

Banning payday loans may be a good thing in this case as the government works closely with the public on more affordable loans.