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Permafrost is thawing so fast it’s gouging holes in the Arctic

Global warming has shown that permafrost is not so permanent after all.

Orjan F. Ellingvag/Dagens Naringsliv/Corbis via Getty Images

Residents of the small Alaskan town Kongiganak can no longer bury their dead. Their cemetery has become a marshy swamp, sucking graves into the once frozen ground.


On the island of Sarichef near the Bering Strait, the village of Shishmaref is shrinking so fast locals are considering relocating it entirely.

Global warming has shown that permafrost is not so permanent after all. And as it begins to melt, it is reshaping the Arctic.

The rapidly thawing ice layer is creating great sinkholes and hollows across the region as the ground begins to collapse in on itself. Erosion and landslides have become a problem without the ice that once held the soil together.

Permafrost – any area of land that remains frozen for at least two years – can vary from less than a metre thick to more than 1,500 metres. Some of it is tens of thousands of years old.

In some areas, it is simply frozen rock. But in other parts, soils and organic matter have acted like a sponge and taken in water which has subsequently frozen. As ice, water takes up a larger volume than its liquid form, but once melted, great pits are created in the land.

Arctic Permafrost Thawing of the arctic permafrost. Image: Nature

A problem multiplied

But the problem extends beyond an increasingly pock-marked landscape.

Scientists have known for years that melting permafrost will release greenhouse gases stored within and under it, creating a climate change feedback loop with the potential to warm our planet even faster. Rather than acting as a carbon sink, permafrost becomes a source of emissions.

Melting permafrost creates greenhouse gasses

Melting permafrost creates a vicious circle of greenhouse gas emissions and global warming.

Image: UNEP

But the abrupt melting of the permafrost layer in some places, caused by warmer polar temperatures, could mean far more carbon is released than previously estimated, according to a new study in Nature Geoscience.

Less than one-fifth of the permafrost zone is likely to see this abrupt thawing, but its impact on the surrounding landscape means up to half of permafrost carbon could be affected.

Existing climate change models are based on gradual thawing of the permafrost layer caused by seasonal temperature fluctuations and fail to take into account the impact of more rapid thawing. This means we need to put in place measures to counteract human-induced emissions more quickly than we thought.

But David Olefeldt, who coauthored the paper in Nature Geoscience, warns against over-dramatizing the problem.

"The permafrost carbon feedback is not the proverbial climate bomb – but is it an important climate change accelerator which we do need to take into account.

"Future greenhouse gas emissions from thawing permafrost [will be] significantly smaller than current human greenhouse gas emissions, but emissions from permafrost thaw are large enough that they are important to take into consideration when projecting future climate change and when setting emissions targets for international negotiations."

The Arctic is warming faster than anywhere else on the planet. Temperatures have risen by 1℃ in the last decade alone, causing ice sheets to melt and sea levels to rise while threatening wildlife.

Getting a handle on warming temperatures at our earth's poles is crucial if we are to keep global warming within agreed limits.

Reprinted with permission of the World Economic Forum. Read the original article.

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If you don't practice accountability at work you're letting the formula for success slip right through your hands.

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  • What is accountability? It's a tool for improving performance and, once its potential is thoroughly understood, it can be leveraged at scale in any team or organization.
  • In this lesson for leaders, managers, and individuals, Shideh Sedgh Bina, a founding partner of Insigniam and the editor-in-chief of IQ Insigniam Quarterly, explains why it is so crucial to success.
  • Learn to recognize the mindset of accountable versus unaccountable people, then use Shideh's guided exercise as a template for your next post-project accountability analysis—whether that project was a success or it fell short, it's equally important to do the reckoning.

What if Middle-earth was in Pakistan?

Iranian Tolkien scholar finds intriguing parallels between subcontinental geography and famous map of Middle-earth

Could this former river island in the Indus have inspired Tolkien to create Cair Andros, the ship-shaped island in the Anduin river?

Image: Mohammad Reza Kamali, reproduced with kind permission
Strange Maps
  • J.R.R. Tolkien himself hinted that his stories are set in a really ancient version of Europe.
  • But a fantasy realm can be inspired by a variety of places; and perhaps so is Tolkien's world.
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Giant whale sharks have teeth on their eyeballs

The ocean's largest shark relies on vision more than previously believed.

An eight-metre-long Whale shark swims with other fish at the Okinawa Churaumi Aquarium on February 26, 2010 in Motobu, Okinawa, Japan.

Photo by Koichi Kamoshida/Getty Images
Surprising Science
  • Japanese researchers discovered that the whale shark has "tiny teeth"—dermal denticles—protecting its eyes from abrasion.
  • They also found the shark is able to retract its eyeball into the eye socket.
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A massive star has mysteriously vanished, confusing astronomers

A gigantic star makes off during an eight-year gap in observations.

Image source: ESO/L. Calçada
Surprising Science
  • The massive star in the Kinsman Dwarf Galaxy seems to have disappeared between 2011 and 2019.
  • It's likely that it erupted, but could it have collapsed into a black hole without a supernova?
  • Maybe it's still there, but much less luminous and/or covered by dust.

A "very massive star" in the Kinman Dwarf galaxy caught the attention of astronomers in the early years of the 2000s: It seemed to be reaching a late-ish chapter in its life story and offered a rare chance to observe the death of a large star in a region low in metallicity. However, by the time scientists had the chance to turn the European Southern Observatory's (ESO) Very Large Telescope (VLT) in Paranal, Chile back around to it in 2019 — it's not a slow-turner, just an in-demand device — it was utterly gone without a trace. But how?

The two leading theories about what happened are that either it's still there, still erupting its way through its death throes, with less luminosity and perhaps obscured by dust, or it just up and collapsed into a black hole without going through a supernova stage. "If true, this would be the first direct detection of such a monster star ending its life in this manner," says Andrew Allan of Trinity College Dublin, Ireland, leader of the observation team whose study is published in Monthly Notices of the Royal Astronomical Society.

So, em...

Between astronomers' last look in 2011 and 2019 is a large enough interval of time for something to happen. Not that 2001 (when it was first observed) or 2019 have much meaning, since we're always watching the past out there and the Kinman Dwarf Galaxy is 75 million light years away. We often think of cosmic events as slow-moving phenomena because so often their follow-on effects are massive and unfold to us over time. But things happen just as fast big as small. The number of things that happened in the first 10 millionth of a trillionth of a trillionth of a trillionth of a second after the Big Bang, for example, is insane.

In any event, the Kinsman Dwarf Galaxy, or PHL 293B, is far way, too far for astronomers to directly observe its stars. Their presence can be inferred from spectroscopic signatures — specifically, PHL 293B between 2001 and 2011 consistently featured strong signatures of hydrogen that indicated the presence of a massive "luminous blue variable" (LBV) star about 2.5 times more brilliant than our Sun. Astronomers suspect that some very large stars may spend their final years as LBVs.

Though LBVs are known to experience radical shifts in spectra and brightness, they reliably leave specific traces that help confirm their ongoing presence. In 2019 the hydrogen signatures, and such traces, were gone. Allan says, "It would be highly unusual for such a massive star to disappear without producing a bright supernova explosion."

The Kinsman Dwarf Galaxy, or PHL 293B, is one of the most metal-poor galaxies known. Explosive, massive, Wolf-Rayet stars are seldom seen in such environments — NASA refers to such stars as those that "live fast, die hard." Red supergiants are also rare to low Z environments. The now-missing star was looked to as a rare opportunity to observe a massive star's late stages in such an environment.

Celestial sleuthing

In August 2019, the team pointed the four eight-meter telescopes of ESO's ESPRESSO array simultaneously toward the LBV's former location: nothing. They also gave the VLT's X-shooter instrument a shot a few months later: also nothing.

Still pursuing the missing star, the scientists acquired access to older data for comparison to what they already felt they knew. "The ESO Science Archive Facility enabled us to find and use data of the same object obtained in 2002 and 2009," says Andrea Mehner, an ESO staff member who worked on the study. "The comparison of the 2002 high-resolution UVES spectra with our observations obtained in 2019 with ESO's newest high-resolution spectrograph ESPRESSO was especially revealing, from both an astronomical and an instrumentation point of view."

Examination of this data suggested that the LBV may have indeed been winding up to a grand final sometime after 2011.

Team member Jose Groh, also of Trinity College, says "We may have detected one of the most massive stars of the local Universe going gently into the night. Our discovery would not have been made without using the powerful ESO 8-meter telescopes, their unique instrumentation, and the prompt access to those capabilities following the recent agreement of Ireland to join ESO."

Combining the 2019 data with contemporaneous Hubble Space Telescope (HST) imagery leaves the authors of the reports with the sense that "the LBV was in an eruptive state at least between 2001 and 2011, which then ended, and may have been followed by a collapse into a massive BH without the production of an SN. This scenario is consistent with the available HST and ground-based photometry."

Or...

A star collapsing into a black hole without a supernova would be a rare event, and that argues against the idea. The paper also notes that we may simply have missed the star's supernova during the eight-year observation gap.

LBVs are known to be highly unstable, so the star dropping to a state of less luminosity or producing a dust cover would be much more in the realm of expected behavior.

Says the paper: "A combination of a slightly reduced luminosity and a thick dusty shell could result in the star being obscured. While the lack of variability between the 2009 and 2019 near-infrared continuum from our X-shooter spectra eliminates the possibility of formation of hot dust (⪆1500 K), mid-infrared observations are necessary to rule out a slowly expanding cooler dust shell."

The authors of the report are pretty confident the star experienced a dramatic eruption after 2011. Beyond that, though:

"Based on our observations and models, we suggest that PHL 293B hosted an LBV with an eruption that ended sometime after 2011. This could have been followed by
(1) a surviving star or
(2) a collapse of the LBV to a BH [black hole] without the production of a bright SN, but possibly with a weak transient."

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