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Ice loss to add 0.4C to global temperatures: Study

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The loss of billions of tons of ice from Earth’s frozen spaces is likely to increase global temperatures by an additional 0.4 degrees Celsius, according to research Tuesday highlighting the danger of a “vicious circle” of warming.

Arctic summer sea ice levels have declined by more than 10 percent each decade since the late 1970s and mountain glaciers have shed roughly 250 billion tons of ice annually over the last century.

Ice loss from the West Antarctic and Greenland ice sheets is accelerating and already outstripping what scientists until recently believed to be the worst-case melt scenarios.

Decades of studies have sought to quantify how Earth’s melting ice will contribute to sea level rise — Antarctica and Greenland alone contain enough frozen water to boost oceans’ height by around 60 meters.

But little research has tried to predict how ice loss will add to the already 1.0 degree C of global warming emissions from fossil fuels since the start of the Industrial Era.

Scientists at Germany’s Potsdam Institute for Climate Impact Research (PIK) used a climate model that includes components on atmosphere, ocean, sea- and land-ice data to predict temperature change from ice loss under a variety of emissions scenarios.

They found that under current levels of atmospheric CO2 — roughly 400 parts per million — the melting of Arctic sea ice, mountain glaciers and the polar ice caps would raise temperatures by 0.4C.

That’s on top of the 1.5C of warming our current emissions levels have rendered all but inevitable, and the safer cap on global warming aimed for in the Paris climate accord.

The main driver of temperature gain from ice loss would be due to a process known as albedo feedback, in which heat reflective bright ice is replaced by absorbent darker sea water and/or soil.

“If global ice masses shrink, this changes how much of the sunlight that hits the Earth’s surface is reflected back into space,” said lead author Nico Wunderling.

He likened the albedo effect to wearing either white or black clothes in summer.

“If you wear dark, you heat up more easily,”  Wunderling noted.

This is one of Earth’s so-called climate “feedback loops”, in which increased temperatures lead to further ice loss, which in turn further increases temperatures.

Tipping point

Other ways that temperatures would rise further as ice receded include increased water vapor in the atmosphere, increasing the greenhouse effects, said authors of the study published in Nature Communications.

Looking solely at Arctic sea ice — which unlike polar ice caps might be totally absent during summer months within decades — they found its melt would contribute 0.2C to global temperatures alone.

The largest ice masses in Greenland and West Antarctica, by comparison, are huge and will likely take centuries to melt fully even if emissions continue their unabated growth.

But the authors highlighted the risk that those enormous bodies of frozen water could soon reach a point of no return as temperatures creep ever higher.

Given the unknowns surrounding ice cap tipping points, Wunderling told AFP it would be best to act in “a risk-averse” way and try to drag down emissions as soon as possible.

“With continued global warming, it becomes more and more likely that we cross tipping points -– not just in the ice-sheets, but also in other parts of the climate system,” he said.

“If the Paris Agreement is fulfilled we can avoid many of the strongest and potentially irreversible impacts on Earth’s ice masses, the global climate and humanity.”

 

 

 

Source:- The Jakarta Post – Jakarta Post

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Many Canadians gaining weight during COVID-19: poll – BarrieToday

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OTTAWA — A new poll suggests many Canadians are gaining weight because they’re eating more and exercising less during COVID-19 pandemic. 

Nearly one-third of respondents in the survey conducted by Leger and the Association for Canadian Studies said they have put on weight since March, compared to 15 per cent who said they lost weight over that time.

As well, about one-third of respondents said they’re exercising less, while 16 per cent said they’re working out more since the first wave of the pandemic landed in Canada in the spring.

Jack Jedwab, president of the Association for Canadian Studies, suggested that one reason may be a rush for comfort food to deal with pandemic-related anxieties.

Respondents in the survey who said they were “very afraid” of COVID-19 were more likely to report gaining weight, eating more and exercising less. 

“The more anxiety you have, the more likely it is that you know you’re eating more,” Jedwab said.

“People who are least anxious about COVID (are) the ones that are not eating more than usual and are not gaining weight.”

The online survey of 1,516 Canadians was conducted Oct. 29-31 and cannot be assigned a margin of error because internet-based polls are not considered random samples.

Dr. Yoni Freedhoff, an associate professor of family medicine at the University of Ottawa, said there are plausible reasons to connect weight gain or loss with the pandemic, but he hadn’t seen any studies to convince him that’s the case. 

Some people are “not reliant on restaurants constantly” and “cooking more frequently in their homes,” which Freedhoff said may be leading to weight loss or better dietary choices. Others are eating more, he said, relying on comfort food “because they’re anxious as a consequence of the pandemic, or the tragedies that have gone on in their lives.”

Jedwab said the country needs to also be mindful of mental health issues that can affect the physical health of Canadians. 

“With the winter coming, it’ll be even more challenging, in some parts of the country, to maintain a healthy lifestyle in terms of walking, in terms of doing basic things that will help us address our anxieties,” he said, pointing to lack of access for some to gyms subject to local lockdowns.

Some of those exercise classes have gone online. Gabriel Shaw, a kinesiologist from Victoria, B.C. said he has offered virtual classes to give his clients an chance to be physically active.

Shaw said the classes don’t provide people with a sense of community like in-person classes, which he said is important for some people to exercise consistently. 

“The best bet for people is to find a way they can enjoy it. That might be going out for a social distance walk or hike or run or bike with a friend,” Shaw said. “That might be finding a Zoom thing that you can get on like dancing or even other activities where you have friends.”

Shaw said people should also try learn a new skill like dancing, yoga, rock climbing, or take up running to keep things fresh and enjoyable, which is key to exercising long and well. 

This report by The Canadian Press was first published Nov. 24, 2020

——
This story was produced with the financial assistance of the Facebook and Canadian Press News Fellowship.

Maan Alhmidi, The Canadian Press

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MOXIE Could Help Future Rockets Launch Off Mars – NASA's Mars Exploration Program – NASA Mars Exploration

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NASA’s Perseverance rover carries a device to convert Martian air into oxygen that, if produced on a larger scale, could be used not just for breathing, but also for fuel.


One of the hardest things about sending astronauts to Mars will be getting them home. Launching a rocket off the surface of the Red Planet will require industrial quantities of oxygen, a crucial part of propellant: A crew of four would need about 55,000 pounds (25 metric tons) of it to produce thrust from 15,000 pounds (7 metric tons) of rocket fuel.

That’s a lot of propellant. But instead of shipping all that oxygen, what if the crew could make it out of thin (Martian) air? A first-generation oxygen generator aboard NASA’s Perseverance rover will test technology for doing exactly that.

The Mars Oxygen In-Situ Resource Utilization Experiment, or MOXIE, is an experimental instrument that stands apart from Perseverance’s primary science. One of the rover’s main purposes is capturing returnable rock samples that could carry signs of ancient microbial life. While Perseverance has a suite of instruments geared toward helping achieve that goal, MOXIE is focused solely on the engineering required for future human exploration efforts.

Since the dawn of the space age, researchers have talked about in-situ resource utilization, or ISRU. Think of it as living off the land and using what’s available in the local environment. That includes things like finding water ice that could be melted for use or sheltering in caves, but also generating oxygen for rocket fuel and, of course, breathing.

Breathing is just a side benefit of MOXIE’s true goal, said Michael Hecht of the Massachusetts Institute of Technology, the instrument’s principal investigator. Rocket propellant is the heaviest consumable resource that astronauts will need, so being able to produce oxygen at their destination would make the first crewed trip to Mars easier, safer, and cheaper.

“What people typically ask me is whether MOXIE is being developed so astronauts have something to breathe,” Hecht said. “But rockets breathe hundreds of times as much oxygen as people.”



Components of MOXIE: An illustration of MOXIE and its components. An air pump pulls in carbon dioxide gas from the Martian atmosphere, which is then regulated and fed to the Solid OXide Electrolyzer (SOXE), where it is electrochemically split to produce pure oxygen. Credit: NASA/JPL-Caltech. Download image ›

Making Oxygen Requires Heat

Mars’ atmosphere poses a major challenge for human life and rocket propellant production. It’s only 1% as thick as Earth’s atmosphere and is 95% carbon dioxide.

MOXIE pulls in that air with a pump, then uses an electrochemical process to separate two oxygen atoms from each molecule of carbon dioxide, or CO2. AnchorAs the gases flow through the system, they are analyzed to check how much oxygen has been produced, how pure it is, and how efficiently the system is working. All the gases are vented back into the atmosphere after each experiment is run.

Powering this electrochemical conversion requires a lot of heat – about 1,470 degrees Fahrenheit (800 degrees Celsius). Because of those high temperatures, MOXIE, which is a little larger than a toaster, features a variety of heat-tolerant materials. Special 3D-printed nickel alloy parts help distribute the heat within the instrument, while superlight insulation called aerogel minimizes the power needed to keep it at operating temperatures. The outside of MOXIE is coated in a thin layer of gold, which is an excellent reflector of infrared heat and keeps those blistering temperatures from radiating into other parts of Perseverance.

“MOXIE is designed to make about 6 to 10 grams of oxygen per hour – just about enough for a small dog to breathe,” said Asad Aboobaker, a MOXIE systems engineer at NASA’s Jet Propulsion Laboratory in Southern California. “A full-scale system geared to make (propellant for the flight home) would need to scale up oxygen production by about 200 times what MOXIE will create.”

[embedded content]

Could NASA’s MOXIE Help Astronauts Breathe on Mars? MOXIE engineer Asad Aboobaker of JPL explains how the instrument works in this video interview. Credit: NASA/JPL-Caltech. Download video ›

The Future Martians

Hecht estimates that a full-scale MOXIE system on Mars might be a bit larger than a household stove and weigh around 2,200 pounds (1,000 kilograms) – almost as much as Perseverance itself. Work is ongoing to develop a prototype for one in the near future.

The team expects to run MOXIE about 10 times over the course of one Mars year (two Earth years), allowing them to watch how well it works in varying seasons. The results will inform the design of future oxygen generators.

“The commitment to developing MOXIE shows that NASA is serious about this,” Hecht said. “MOXIE isn’t the complete answer, but it’s a critical piece of it. If successful, it will show that future astronauts can rely on this technology to help get them home safely from Mars.”

More About the Mission

A key objective for Perseverance’s mission on Mars is astrobiology, including the search for signs of ancient microbial life. The rover will characterize the planet’s geology and past climate, pave the way for human exploration of the Red Planet, and be the first mission to collect and cache Martian rock and regolith (broken rock and dust).

Subsequent missions, currently under consideration by NASA in cooperation with ESA (the European Space Agency), would send spacecraft to Mars to collect these cached samples from the surface and return them to Earth for in-depth analysis.

The Mars 2020 mission is part of a larger program that includes missions to the Moon as a way to prepare for human exploration of the Red Planet. Charged with returning astronauts to the Moon by 2024, NASA will establish a sustained human presence on and around the Moon by 2028 through NASA’s Artemis lunar exploration plans.

JPL, which is managed for NASA by Caltech in Pasadena, California, built and manages operations of the Perseverance rover.

For more about Perseverance:

mars.nasa.gov/mars2020/

nasa.gov/perseverance

News Media Contacts
Andrew Good
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-2433
andrew.c.good@jpl.nasa.gov

Alana Johnson / Grey Hautaluoma
NASA Headquarters, Washington
202-672-4780 / 202-358-0668
alana.r.johnson@nasa.gov / grey.hautaluoma-1@nasa.gov

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Many Canadians gaining weight during COVID-19: poll – Medicine Hat News

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By Maan Alhmidi, The Canadian Press on November 24, 2020.

People work out at an outdoor gym in downtown Montreal, on Friday, Nov. 6, 2020. A new poll suggests many Canadians are gaining weight because they’re eating more and exercising less during COVID-19 pandemic. THE CANADIAN PRESS/Paul Chiasson

OTTAWA – A new poll suggests many Canadians are gaining weight because they’re eating more and exercising less during COVID-19 pandemic.

Nearly one-third of respondents in the survey conducted by Leger and the Association for Canadian Studies said they have put on weight since March, compared to 15 per cent who said they lost weight over that time.

As well, about one-third of respondents said they’re exercising less, while 16 per cent said they’re working out more since the first wave of the pandemic landed in Canada in the spring.

Jack Jedwab, president of the Association for Canadian Studies, suggested that one reason may be a rush for comfort food to deal with pandemic-related anxieties.

Respondents in the survey who said they were “very afraid” of COVID-19 were more likely to report gaining weight, eating more and exercising less.

“The more anxiety you have, the more likely it is that you know you’re eating more,” Jedwab said.

“People who are least anxious about COVID (are) the ones that are not eating more than usual and are not gaining weight.”

The online survey of 1,516 Canadians was conducted Oct. 29-31 and cannot be assigned a margin of error because internet-based polls are not considered random samples.

Dr. Yoni Freedhoff, an associate professor of family medicine at the University of Ottawa, said there are plausible reasons to connect weight gain or loss with the pandemic, but he hadn’t seen any studies to convince him that’s the case.

Some people are “not reliant on restaurants constantly” and “cooking more frequently in their homes,” which Freedhoff said may be leading to weight loss or better dietary choices. Others are eating more, he said, relying on comfort food “because they’re anxious as a consequence of the pandemic, or the tragedies that have gone on in their lives.”

Jedwab said the country needs to also be mindful of mental health issues that can affect the physical health of Canadians.

“With the winter coming, it’ll be even more challenging, in some parts of the country, to maintain a healthy lifestyle in terms of walking, in terms of doing basic things that will help us address our anxieties,” he said, pointing to lack of access for some to gyms subject to local lockdowns.

Some of those exercise classes have gone online. Gabriel Shaw, a kinesiologist from Victoria, B.C. said he has offered virtual classes to give his clients an chance to be physically active.

Shaw said the classes don’t provide people with a sense of community like in-person classes, which he said is important for some people to exercise consistently.

“The best bet for people is to find a way they can enjoy it. That might be going out for a social distance walk or hike or run or bike with a friend,” Shaw said. “That might be finding a Zoom thing that you can get on like dancing or even other activities where you have friends.”

Shaw said people should also try learn a new skill like dancing, yoga, rock climbing, or take up running to keep things fresh and enjoyable, which is key to exercising long and well.

This report by The Canadian Press was first published Nov. 24, 2020

– –
This story was produced with the financial assistance of the Facebook and Canadian Press News Fellowship.

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