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Earth’s ice sheets tracking worst-case climate scenarios – DAWN.com

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PARIS: The Greenland and Antarctic ice sheets, which hold enough frozen water to lift oceans 65 metres, are tracking the UN’s worst-case scenarios for sea level rise, researchers have said, highlighting flaws in current climate change models.

Mass loss caused by melt-water and crumbling ice from 2007 to 2017 aligned with the most extreme forecasts from the Intergovernmental Panel for Climate Change (IPCC), which see the two ice sheets adding up to 40 centimetres (nearly 16 inches) to global oceans by 2100, they reported on Monday in Nature Climate Change.

Such an increase would have a devastating impact worldwide, increasing the destructive power of storm surges and exposing coastal regions home to hundreds of millions of people to repeated and severe flooding.

That is nearly three times more than mid-range projections from the IPCC’s last major Assessment Report in 2014, which predicted a 70 centimetre rise in sea level from all sources, including mountain glaciers and the expansion of ocean water as it warms.

Despite this clear mismatch between the observed reality of accelerating ice sheet disintegration and the models tracking those trends, a special IPCC report last year on the planet’s frozen regions maintained the same end-of-century projections for Greenland, and allowed for only a small increase from Antarctica under the highest greenhouse gas emissions scenario.

“We need to come up with a new worst-case scenario for the ice sheets because they are already melting at a rate in line with our current one,” lead author Thomas Slater, a researcher at the Centre for Polar Observation and Modelling at the University of Leeds, said.

“Sea level projections are critical in helping governments plan climate policy, mitigation and adaptation strategies.

“If we underestimate future sea level rise, then these measures may be inadequate and leave coastal communities vulnerable.” Ice sheet losses at the upper end of the IPCC forecasts would by itself expose some 50 million people to annual coastal flooding worldwide by mid-century, according to research published last year.

Several factors explain why the climate models underlying UN projections for sea level might have given short shrift to ice sheets, according to the new analysis.

Ice sheet models do well in describing the long-term impact of gradual global warming, which has seen temperatures at the poles rise far more quickly than for the planet as a whole.

But they have failed to account for short-term fluctuations in weather patterns that are, themselves, deeply influenced by climate change.

“For Greenland, much of the ice loss is now being driven by surface melt events during hot summers — processes not captured in the AR5 simulations,” said Slater, referring to the 2014 IPCC report, the fifth since 1992.

“We need to understand these better to improve our sea level rise predictions.” Until the turn of the 21st century, the West Antarctic and Greenland ice sheets generally accumulated as much mass as they shed. Runoff, in other words, was compensated by fresh snowfall.

Published in Dawn, September 2nd, 2020

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Tla'amin Nation COVID-19 survivor warns virus spreads easily and recovery is difficult – Yahoo News Canada

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Brandon Peters was keeping his bubble small this summer.

The Vancouver resident planted a “COVID garden” and planned on playing it as safe as possible during the pandemic. Those plans were derailed, and so was his health, after attending the funeral of a loved one on Tla’amin Nation territory on the north Sunshine Coast near Powell River, B.C. 

Peters, a member of the nation, was diagnosed with COVID-19 within days of the visit. After spending most of September in bed fighting the virus, he is now speaking out publicly to warn people just how hard that fight can be.

<p class="canvas-atom canvas-text Mb(1.0em) Mb(0)–sm Mt(0.8em)–sm" type="text" content=""I opened myself up for just a minute, a couple people hugged me, and I got sick within a couple of days," said Peters Thursday on On The Island.” data-reactid=”15″>”I opened myself up for just a minute, a couple people hugged me, and I got sick within a couple of days,” said Peters Thursday on On The Island.

He said when he left the north Sunshine Coast, he was so overcome with fatigue he could not complete the 80 kilometre drive to the Langdale Ferry Terminal to catch a ferry to the Lower Mainland. Instead, he had to pull over and sleep.

Peters did make it back to Vancouver though, only to have a horrible night where he said he felt “deep pain” throughout his body and had an excruciating headache. 

<p class="canvas-atom canvas-text Mb(1.0em) Mb(0)–sm Mt(0.8em)–sm" type="text" content="Down for the count” data-reactid=”18″>Down for the count

The next day he got tested for COVID-19. The day after that, he learned he was positive.

For the next few weeks, Peters lay in bed so overcome with exhaustion he said he couldn’t eat anything and drank only water.

“The fatigue was so intense I would have to gather my gumption just to go to the washroom,” he said.

In a recently uploaded video on the Tla’amin Nation’s Facebook page, Peters says he wondered every day while bed-ridden if he was going to make it to see another week.

Fortunately, Peters was never hospitalized and says he now has about 80 per cent of his strength back. Now he wants to tell others his story to try and prevent anyone from going through the harrowing ordeal he did — or worse.

The video is part of sharing that story.

“People might look at me like a leper over the next little while but I think if I help a couple people it will make the video worthwhile,” said Peters.

He said it is important to him that people take the risks of the virus seriously and stop engaging in activities that could put themselves or others at risk.

“This is going to be with us for a while and we need to make those responsible decisions.”

According to a media release from the Tla’amin Nation, there have been 36 positive COVID-19 cases reported in the nation since September 7.

The community is currently in a state of local emergency and non-approved visitors are restricted from Tla’amin land.

<p class="canvas-atom canvas-text Mb(1.0em) Mb(0)–sm Mt(0.8em)–sm" type="text" content="To hear the complete interview with Brandon Peters on On The Island, tap here.” data-reactid=”30″>To hear the complete interview with Brandon Peters on On The Island, tap here.

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NASA says bus-sized asteroid safely buzzed Earth | TheHill – The Hill

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NASA reported that an asteroid roughly the size of a school bus passed by Earth early Thursday morning, traveling from about 13,000 miles away. 

According to the government space agency, the rock made its closest approach to Earth around 7 a.m. EDT on Thursday, passing over the Southeastern Pacific Ocean. 

NASA first reported on the asteroid on Tuesday, saying that scientists estimated the space rock was about 15 to 30 feet wide. Scientists predict that the asteroid will now travel around the sun and not make its way back into the Earth’s vicinity until 2041. 

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Paul Chodas, director of the Center for Near-Earth Object Studies at NASA’s Jet Propulsion Laboratory in Southern California, said Tuesday that space rocks such as these are relatively common and are not considered a threat to life on Earth. 

“There are a large number of tiny asteroids like this one, and several of them approach our planet as close as this several times every year,” Chodas said. “In fact, asteroids of this size impact our atmosphere at an average rate of about once every year or two.”

He added that “the detection capabilities of NASA’s asteroid surveys are continually improving, and we should now expect to find asteroids of this size a couple days before they come near our planet.” 

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NASA said that while Thursday’s asteroid was not on a trajectory to hit Earth, it would have likely broken up in the atmosphere and become a bright meteor, known as a fireball, before causing any damage. 

This comes a month after NASA reported that an asteroid is on a path toward Earth one day before the U.S. presidential election, although the agency said that the chances of it actually hitting the Earth’s surface are less than 1 percent. NASA confirmed in a statement to The Hill last month that the rock would not pose a threat. 

“If it were to enter our planet’s atmosphere, it would disintegrate due to its extremely small size,” a spokesperson said in the statement. “NASA has been directed by Congress to discover 90% of the near-Earth asteroids larger than 140 meters (459 feet) in size and reports on asteroids of any size.”

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UM physicists part of international team for historic first – UM Today

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September 24, 2020 — 

UM researchers on an international team of physicists have made the first precise measurement of the weak force between particles in the universe, verifying a theory of the Standard Model of Particle Physics.

Using a device called the the Spallation Neutron Source at the U.S. Department of Energy’s Oak Ridge National Laboratory, the scientists were able to measure the weak force exerted between protons and neutrons by detecting the miniscule electrical signal produced when a neutron and a helium-3 nucleus combined and then decayed moving through a target. 

The result was published in the journal Physical Review Letters.

As described in the online news site Mirage News

The Standard Model describes the basic building blocks of matter in the universe and fundamental forces acting between them. Calculating and measuring the weak force between protons and neutrons is an extremely difficult task.

Their finding yielded the smallest uncertainty of any comparable weak force measurement in the nucleus of an atom to date, which establishes an important benchmark.

UM physicist Dr. Michael Gericke said:

When a neutron and a helium-3 nucleus combine, the reaction produces an excited, unstable helium-4 isotope, decaying to one proton and one triton (consisting of two neutrons and one proton), both of which produce a tiny but detectable electrical signal as they move through the helium gas in the target cell.”

Gericke led the group that built the combined helium-3 target and detector system designed to pick up the very small signals and led the subsequent analysis.

Read the Mirage News story here.

An analysis and explanation of the discovery is here.

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