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Why increased rainfall in the Arctic is bad news for the whole world – Republic World

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Loughborough (UK), Dec 2 (The Conversation) Before the end of this century, most of the Arctic will for the first time receive more rain than snow across a whole year. That’s one of the key findings of a new study on precipitation in the Arctic which has major implications – not just for the polar region, but for the whole world.

While a reduction in frozen ocean surface is one of the most widely recognised impacts of Arctic warming, it has also long been anticipated that a warmer Arctic will be a wetter one too, with more intense cycling of water between land, atmosphere and ocean.

The shift from a frozen region towards a warmer, wetter Arctic is driven by the capacity of a warmer atmosphere to hold more moisture, by increased rates of evaporation from ice-free oceans, and by the jet stream relaxing.

The Arctic water cycle is expected to shift from a snow-dominated one towards a rain-dominated one during the 21st century, although the timing of this is uncertain. Now, a team of scientists have published a study in the journal Nature Communications which suggests that this shift will occur earlier than previously projected.

The effect will be particularly strong in autumn, with most of the Arctic Ocean, Siberia and the Canadian Archipelago becoming rain-dominated by the 2070s instead of the 2090s.

Warmer and wetter isn’t necessarily better Such a profound change to the Arctic water cycle will inevitably affect ecosystems on land and in the ocean. You might intuitively expect that a warmer and wetter Arctic would be very favourable for ecosystems – rainforests have many more species than tundra, after all. But the plants and animals of the Arctic have evolved for cold conditions over millions of years, and their relatively simple food web is vulnerable to disturbance.

For example, warmer temperatures can cause larval insects to emerge earlier, before the fish species that feed upon them have hatched. More rainfall means more nutrients washed into rivers, which should benefit the microscopic plants at the base of the food chain.

However, this also makes rivers and coastal waters more murky, blocking light needed for photosynthesis and potentially clogging filter-feeding animals, including some whales or sharks. Brackish water typically supports fewer species than either freshwater or seawater, so increasing flows of freshwater offshore may well reduce the range of animals and plants along Arctic coasts.

Further into the Arctic Ocean, there are more reasons to doubt the potential benefits of warmer temperatures and greater freshwater circulation. The dissolved constituents of rainfall, river water and melting snow and ice reduce the alkalinity of Arctic surface waters, which makes it harder for marine organisms to build shells and skeletons, and limits chemical neutralisation of the acidifying effects of CO₂ absorbed in seawater.

At the same time, rivers flowing through degrading permafrost will wash organic material into the sea that bacteria can convert to CO₂, making the ocean more acidic. Fresh water also essentially floats on denser seawater.

This causes the ocean to become stratified, impeding exchanges of nutrients and organisms between the deep sea and the surface, and restricting biological activity. Therefore the likely impacts of a warmer, wetter Arctic on food webs, biodiversity and food security are uncertain, but are unlikely to be uniformly positive.

Arctic change is decades ahead of global averages Temperature increases in the Arctic have raced ahead of the global average. This will only be reinforced as snowfall is reduced and rainfall increases, since snow reflects the sun’s energy back into space. As the land becomes less snowy and less reflective, bare ground will absorb more solar energy, and thus will warm up.

The Arctic is set to continue warming faster than elsewhere, further diminishing the difference in temperature between the warmest and coldest parts of the planet, with complex implications for the oceans and atmosphere.

The recent COP26 climate summit in Glasgow focused on efforts to “keep 1.5°C alive”. It is worth remembering that the 1.5°C figure is a global average, and that the Arctic will warm by at least twice as much as this, even for modest projections.

The new study underscores the importance of the global 1.5°C target for the Arctic. For instance, at that level of warming Greenland is expected to transition to a rainfall-dominated climate for most of the year. While at 3°C warming, which is close to the current pathway based on existing policies rather than pledges, most regions of the Arctic will transition to a rainfall-dominated climate before the end of the 21st-century.

It’s research that adds further weight to calls for improved monitoring of Arctic hydrological systems and to the growing awareness of the considerable impacts of even small increments of atmospheric warming. (The Conversation) SCY SCY

(Disclaimer: This story is auto-generated from a syndicated feed; only the image & headline may have been reworked by www.republicworld.com)

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Awesome Photo Shows James Webb Space Telescope in Deep Space Home – Futurism

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It’s amazing.

Parking Spot

Breathe easy, fellow space nerds. 

The much-anticipated James Webb Space Telescope (JWST) is unfurled and parked in its final orbit, roughly one million miles away from Earth.

While we’ll likely never see it up close and personal ever again, a remotely-controlled telescope has provided us with one of the first images of the Webb in orbit — showing the JWST as a distant dot that’s virtually indistinguishable amongst the stars and galaxies in the image. 

Check out the photo for yourself below:

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Credit: Virtual Telescope Project

Robot Astronomer

The stunning image itself was captured by a 17-inch telescope dubbed “Elena.” It’s managed by the Virtual Telescope Project 2.0, which provides astronomers access to two remotely-controlled robotic telescopes in Rome, Italy. 

The photo was snapped just as the Webb arrived at its final destination at the Lagrange Point 2 (L2) — and if that’s not enough for you, they were able to cobble together a short video of it moving through the inky blackness of space. 

Webb’s Future

NASA initially estimated that the Webb had enough fuel for a roughly 10 year mission. During that time, scientists hope that it’ll provide us with the most detailed — and hopefully revealing — images of deep space we’ve ever seen.  

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However, some experts believe it’ll be able to work for a lot longer than that. 

“You’ve heard numbers around 20 years. We think that’s probably a good ballpark,” Keith Parrish, the JWST observatory commissioning manager at NASA, said in a press teleconference attended by SpaceNews  after the Webb reached L2 on Monday.  “This is capping off just a remarkable 30 days.”

So hopefully, we’ll have plenty more images of — and from — the Webb for a long time to come. 

More on James Webb Space Telescope: Famed Physicist: Soon-to-Launch Telescope Likely to Discover Alien Life

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Astronomers spy powerful deep-space object unlike anything seen before – CNET

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An artist’s impression of what the object might look like if it’s a magnetar. Magnetars are incredibly magnetic neutron stars, some of which sometimes produce radio emissions. Known magnetars rotate every few seconds, but, theoretically, “ultra-long-period magnetars” could rotate much more slowly.


ICRAR

A team led by astronomers in Australia has discovered a brand new type of object in deep space that behaves in bizarre and mysterious ways never seen before. 

Something about 4,000 light-years away, which is relatively close in our cosmic neighborhood, was seen spinning around and regularly blasting out a massive burst of energy that lasts a full a minute. Even weirder, that bright beam of radiation occurred like clockwork every 18 minutes. 

“It was kind of spooky for an astronomer because there’s nothing known in the sky that does that,” astrophysicist Natasha Hurley-Walker said in a statement. 

The behavior is similar to that of a pulsar or magnetar, which spin around as they blast out pulses of energy that can be detected here on Earth. But pulsars pulse very quickly, usually every few seconds. An object that sends out longer bursts just a few times an hour has never been seen before. 

Hurley-Walker led a team from the Curtin University node of the International Centre for Radio Astronomy Research that made the discovery, with assistance from the Shanghai Astronomical Observatory. She’s also lead author on a paper detailing the find in this week’s issue of the journal Nature. 

This odd object was originally spotted by Curtin student Tyrone O’Doherty using the Murchison Widefield Array telescope in outback Western Australia. The MWA is a radio observatory that can observe a wide swath of the sky over a wide range of frequencies. 

“It’s exciting that the source I identified last year has turned out to be such a peculiar object,” said O’Doherty, who is working on his Ph.D.

The galactic peculiarity could be the collapsed core of a star with an ultra-powerful magnetic field. Hurley-Walker explains that it has the characteristics of something astrophysicists have theorized called an “ultra-long-period magnetar.”

“It’s a type of slowly spinning neutron star that has been predicted to exist theoretically,” she said. “But nobody expected to directly detect one like this because we didn’t expect them to be so bright. Somehow it’s converting magnetic energy to radio waves much more effectively than anything we’ve seen before.”

For now, the unusual object has stopped sending out pulses that we can see, but Hurley-Walker says she is continuing to monitor it with the Murchison Widefield Array telescope in case it starts up again. 

“If it does, there are telescopes across the Southern Hemisphere and even in orbit that can point straight to it,” she added.

She also plans to go back into the MWA’s archives to see if this object is just one member of a larger family that’s gone unnoticed until now. 

“More detections will tell astronomers whether this was a rare one-off event or a vast new population we’d never noticed before.” 

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SpaceX rocket booster on collision course with the moon – Globalnews.ca

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An out-of-control booster from a SpaceX rocket has been drifting through space for seven years, and astronomers say it’s now on a collision course with the moon.

The booster was originally launched from Florida’s Cape Canaveral in February 2015 as part of the Falcon 9 interplanetary mission.

Read more:

Remember that mysterious moon cube? Scientists now know what it is

The booster, also known as the second stage, was left derelict and on a shaky orbit after propelling the National Oceanic and Atmospheric Administration’s Deep Space Climate Observatory far into space to help monitor space weather.

Here, it was left in a kind of purgatory, where it was too far from Earth to tumble back down, but not far enough to escape the gravitational pull of the Earth-moon system.

Bill Gray of space blog projectpluto.com first reported the upcoming crash, and said he believes it’s “the first unintentional case” of space junk colliding with the moon.

Gray, along with other space observers, believes the booster, which weighs approximately four metric tons, will strike the far side of the moon near its equator at 2.58 kilometres per second on March 4.

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Unlike Earth, the moon doesn’t have a thick atmosphere to help break up foreign objects, so the booster is expected to slam into the surface and add another mark to the moon’s already heavily cratered crust.

Astronomers, including Harvard University’s own Jonathan McDowell, say that there’s nothing to worry about — this won’t destroy the moon or really cause much damage.

Even still, it’s tough to predict exactly what will happen and where the booster will hit as there are many extraneous factors like sunlight “pushing” on the rocket and “ambiguity in measuring rotation periods,” which may slightly alter its orbit, according to Gray.

Because it looks like the booster will hit the far side of the moon, it will more than likely not be visible to the naked eye (or with a telescope) from Earth. Additionally, the collision is projected to take place a few days after the new moon, which means the majority of the moon will be obscured from vision anyway.

Read more:

Neil Young threatens to pull music from Spotify over Joe Rogan vaccine ‘disinformation’

Interestingly, while this may be the first instance of space junk hitting the moon, it’s not the first time a human-made device has collided with it; NASA launched a rocket at the moon in 2009 — on purpose — in order to detect what would emerge upon impact.

The LCROSS (Lunar Crater Observation and Sensing Satellite) mission and collision, which was not visible from Earth, helped confirm that there is water on the moon.

Many space experts and enthusiasts are excited for the upcoming crash, as it could also inadvertently provide further information about our satellite neighbour.

As of this writing, SpaceX and NASA have not publicly commented on the impending collision.

© 2022 Global News, a division of Corus Entertainment Inc.

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