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Climate change: The ice we’ve lost this decade, visualized – Vox.com

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One of the most poignant climate moments of 2019 was a funeral for ice: an August ceremony in Iceland for the country’s Okjökull glacier. As can be seen in these NASA satellite images, the glacier declined dramatically between 1986 and 2019:

The Ok glacier in Iceland lost its designation as a glacier in 2014 and was mourned over the summer this year.
Nasa Earth Observatory and NASA Earth Observatory

Mourners remembered the once-large patch of ice with a plaque.

“In the next 200 years all our glaciers are expected to follow the same path,” the plaque reads. “This monument is to acknowledge that we know what is happening and what needs to be done. Only you will know if we did it.”

The loss of Okjökull (officially stripped of its glacier status in 2014) was one of many deeply troubling milestones this decade in the world’s frozen regions, known collectively as the cryosphere. The Arctic in particular is warming twice as fast as the global average and experienced many historic heat waves. The warming, in turn, is causing an unprecedented amount of melt in the world’s ice.

The ice sheets on land have critical effects on seawater levels around the world. If all the ice on Greenland were to melt, it would raise global sea levels by 20 feet. If all the ice in Antarctica melted, it would raise sea levels by 190 feet.

That’s just for ice on land. The melt of once-frozen waters is threatening vulnerable species, changing circulation patterns in the ocean, and fueling feedback loops that could cause even more ice to melt.

In this post, we’ll walk through some of the key markers of climate change in the polar regions this decade with visuals, as well as some of the key insights we gained. (We’ve omitted Greenland’s ice sheet only because there aren’t many good images available.) We learned that ice is declining at both poles at an accelerating rate the world hasn’t seen in centuries. We can now see these dramatic changes from space. And we have a much better grasp on what we’ll lose if we don’t slow the emissions destabilizing the global climate.

There are two main categories of ice in the cryosphere. One is the ice that forms on land from precipitation: Two-thirds of the planet’s freshwater is frozen in these ice caps, sheets, and glaciers. The other is the ice that forms from freezing the ocean, known as sea ice.

The extent of sea ice tends to ebb and flow with the seasons, but over the past decade, both the highs and lows have gotten lower.

“If you look at just the last decade, 2010 to 2019, eight out of those 10 years are among the lowest 10,” said Walt Meier, a senior research scientist at the National Snow and Ice Data Center.

You can see that in this graph comparing the extent of Arctic sea ice over the course of a year. It grows in the winter and shrinks in the summer, but in recent years, there’s less of the former and more of the latter.

Christina Animashaun/Vox

The record low was in 2012, but this year isn’t much farther behind. “It’s kind of reinforcing that we’re heading on a downward trend,” Meier said.

But the picture is more bleak when we zoom out to a longer time scale: We are currently in the midst of the fastest decline of Arctic sea ice in 1,500 years.

Christina Animashaun/Vox

And you can see how this has played out in recent decades in this time lapse animation of ice at the North Pole:

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But Meier notes that it’s not just the extent of sea ice that’s changing; the thickness is shrinking as well. It’s a key factor in how much ice survives the summer and how quickly it can regrow in the winter, and we’ve only recently gained a good handle on this with new satellite instruments that can track thickness over time. “The thickness is decreasing as rapidly or more rapidly than the extent,” he said.

The planet’s South Pole is one of its coldest regions, and it’s warming up as well, prompting the rate of ice melt to accelerate. In the past decade, the rate of ice melt in Antarctica tripled compared to 2007. This is on pace to cause six inches of sea level rise by 2100.

Melting ice in Antarctica

Ice melt in Antarctica has accelerated in the past decade.
Javier Zarracina/Vox

You can see some of these dramatic changes playing out in sections of Antarctica, like the Pine Island Glacier. Here is an animation showing the retreat of the glacier since 2000.

The decline of Antarctica’s Pine Island Glacier since 2000.
The decline of Antarctica’s Pine Island Glacier since 2000.

The decline of Antarctica’s Pine Island Glacier since 2000.
NASA Earth Observatory

The trends in ice in Antarctica are a bit more complicated. There are sections of the Antarctic ice sheet where ice is growing in depth, and others where it is declining, as can be seen in this NASA visual looking at the last 25 years:

[embedded content]

Currently, the East Antarctic Ice Sheet, the larger, thicker, cooler, more stable sheet in Antarctica, is unlikely to see major changes in the coming years. But the West Antarctic Ice Sheet is showing signs of an accelerating rate of melt, driven in part by climate change.

Greenhouse gas emissions, meanwhile, climbed ever higher this decade. In 2010, carbon dioxide concentrations peaked at 394 parts per million (ppm), according to observations at the Mauna Loa Observatory. This year, the observatory reported a record high of 414.8 ppm, a concentration not seen on Earth for millions of years.

“At our current rates of increasing emissions, it’s pretty inevitable we’re going to have ice-free summer conditions at some point in the future, probably within the next, three decades,” Meier said. “It’s a matter of ‘when,’ not ‘if’ anymore.”

However, there is uncertainty in how many summers we’ll see without ice in the Arctic, and a key source of that uncertainty is what we’ll do about our greenhouse gas emissions.

The Paris climate agreement set out to limit warming this century to less than 2 degrees Celsius above pre-industrial levels, with a more ambitious target of staying below 1.5 degrees Celsius. Hitting the latter target would require halving global emissions by as soon as 2030, reaching net-zero emissions by 2050, and then net reductions of carbon dioxide in the atmosphere thereafter.

It’s a tall order, but reaching the more-ambitious goal would mean more ice would survive the summer. “In 2 degrees [Celsius] of warming, which is the target set in Paris, it’s likely that we’ll have ice-free summers pretty regularly under those conditions,” Meier said. “But if we hold things to 1.5 degrees [Celsius], which is kind of the ambitious goal, I’m not sure how realistic that is, we’ll likely keep a fair amount of ice around the summer.”

So we’ll likely lose even more from the coldest parts of the world in the coming decade. But the actions we all take will shape just how much is lost.

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India among 11 ‘countries of concern’ on climate change for U.S. spy agencies

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Afghanistan, India and Pakistan were among 11 countries singled out by U.S. intelligence agencies on Thursday as being “highly vulnerable” in terms of their ability to prepare for and respond to environmental and societal crises caused by climate change.

In a new National Intelligence Estimate, the Office of the Director of National Intelligence (ODNI) predicts that global warming will increase geopolitical tensions and risks to U.S. national security in the period up to 2040.

Such estimates are broad U.S. intelligence community assessments. Thursday’s report identifies as particular “countries of concern” Afghanistan, India, Pakistan, Myanmar, Iraq, North Korea, Guatemala, Haiti, Honduras, Nicaragua and Colombia. ODNI posted a declassified version online.

Heat, drought, water availability and ineffective government make Afghanistan specifically worrying. Water disputes are also a key geopolitical flashpoint in India and the rest of South Asia.

The report identifies two additional regions of concern to U.S. intelligence agencies. Climate change is “likely to increase the risk of instability in countries in Central Africa and small island states in the Pacific, which clustered together form two of the most vulnerable areas in the world.”

The report notes disparities around global approaches to tackling climate change, saying countries that rely on fossil fuel exports to support their economies “will continue to resist a quick transition to a zero-carbon world because they fear the economic, political, and geopolitical costs of doing so.”

The report also notes the likelihood of increasing strategic competition over the Arctic. It says that Arctic and non-Arctic states “almost certainly will increase their competitive activities as the region becomes more accessible because of warming temperatures and reduced ice.”

It predicts international competition in the Arctic “will be largely economic but the risk of miscalculation will increase modestly by 2040 as commercial and military activity grows and opportunities are more contested.”

 

(Reporting by Mark Hosenball; Editing by Frances Kerry)

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Mining the moon's water will require a massive infrastructure investment, but should we? – Yahoo News Canada

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<img class="caas-img has-preview" alt="Building a moon base will require extensive resources and infrastructure. (Shutterstock)” src=”https://s.yimg.com/ny/api/res/1.2/.m2KoEuLN10EA5S4WJVJgg–/YXBwaWQ9aGlnaGxhbmRlcjt3PTk2MDtoPTQyNw–/https://s.yimg.com/uu/api/res/1.2/1uRhQ0.2td5TYJER6DobpA–~B/aD02NDE7dz0xNDQwO2FwcGlkPXl0YWNoeW9u/https://media.zenfs.com/en/the_conversation_canada_501/2d6de465d32ef88321836f92f2c4c30b” data-src=”https://s.yimg.com/ny/api/res/1.2/.m2KoEuLN10EA5S4WJVJgg–/YXBwaWQ9aGlnaGxhbmRlcjt3PTk2MDtoPTQyNw–/https://s.yimg.com/uu/api/res/1.2/1uRhQ0.2td5TYJER6DobpA–~B/aD02NDE7dz0xNDQwO2FwcGlkPXl0YWNoeW9u/https://media.zenfs.com/en/the_conversation_canada_501/2d6de465d32ef88321836f92f2c4c30b”>

Building a moon base will require extensive resources and infrastructure. (Shutterstock)

We live in a world in which momentous decisions are made by people often without forethought. But some things are predictable, including that if you continually consume a finite resource without recycling, it will eventually run out.

Yet, as we set our sights on embarking back to the moon, we will be bringing with us all our bad habits, including our urge for unrestrained consumption.

Since the 1994 discovery of water ice on the moon by the Clementine spacecraft, excitement has reigned at the prospect of a return to the moon. This followed two decades of the doldrums after the end of Apollo, a malaise that was symptomatic of an underlying lack of incentive to return.

That water changed everything. The water ice deposits are located at the poles of the moon hidden in the depths of craters that are forever devoid of sunlight.

Since then, not least due to the International Space Station, we have developed advanced techniques that allow us to recycle water and oxygen with high efficiency. This makes the value of supplying local water for human consumption more tenuous, but if the human population on the Moon grows so will demand. So, what to do with the water on the moon?

There are two commonly proposed answers: energy storage using fuel cells and fuel and oxidizer for propulsion. The first is easily dispensed with: fuel cells recycle their hydrogen and oxygen through electrolysis when they are recharged, with very little leakage.

Energy and fuel

The second — currently the primary raison d’être for mining water on the moon — is more complex but no more compelling. It is worth noting that SpaceX uses a methane/oxygen mix in its rockets, so they would not require the hydrogen propellant.

So, what is being proposed is to mine a precious and finite resource and burn it, just like we have been doing with petroleum and natural gas on Earth. The technology for mining and using resources in space has a technical name: in-situ resource utilization.

And while oxygen is not scarce on the moon (around 40 per cent of the moon’s minerals comprise oxygen), hydrogen most certainly is.

Extracting water from the moon

Hydrogen is highly useful as a reductant as well as a fuel. The moon is a vast repository of oxygen within its minerals but it requires hydrogen or other reductant to be freed.

For instance, ilmenite is an oxide of iron and titanium and is a common mineral on the moon. Heating it to around 1,000 C with hydrogen reduces it to water, iron metal (from which an iron-based technology can be leveraged) and titanium oxide. The water may be electrolyzed into hydrogen — which is recycled — and oxygen; the latter effectively liberated from the ilmenite. By burning hydrogen extracted from water, we are compromising the prospects for future generations: this is the crux of sustainability.

But there are other, more pragmatic issues that emerge. How do we access these water ice resources buried near the lunar surface? They are located in terrain that is hostile in every sense of the word, in deep craters hidden from sunlight — no solar power is available — at temperatures of around 40 Kelvin, or -233 C. At such cryogenic temperatures, we have no experience in conducting extensive mining operations.

Read more: US seeks to change the rules for mining the Moon

Peaks of eternal light are mountain peaks located in the region of the south pole that are exposed to near-constant sunlight. One proposal from NASA’s Jet Propulsion Lab envisages beaming sunlight from giant reflectors located at these peaks into craters.

Black and white image of the moon's surface

Black and white image of the moon’s surface

These giant mirrors must be transported from Earth, landed onto these peaks and installed and controlled remotely to illuminate the deep craters. Then robotic mining vehicles can venture into the now-illuminated deep craters to recover the water ice using the reflected solar energy.

Water ice may be sublimed into vapour for recovery by direct thermal or microwave heating – because of its high heat capacity, this will consume a lot of energy, which must be supplied by the mirrors. Alternatively, it may be physically dug out and subsequently melted at barely more modest temperatures.

Using the water

After recovering the water, it needs to be electrolyzed into hydrogen and oxygen. To store them, they should be liquefied for minimum storage tank volume.

Although oxygen can be liquefied easily, hydrogen liquefies at 30 Kelvin (-243 C) at a minimum of 15 bar pressure. This requires extra energy to liquefy hydrogen and maintain it as liquid without boil-off. This cryogenically cooled hydrogen and oxygen (LH2/LOX) must be transported to its location of use while maintaining its low temperature.

So, now we have our propellant stocks for launching stuff from the moon.

This will require a launchpad, which may be located at the moon’s equator for maximum flexibility of launching into any orbital inclination as a polar launch site will be limited to polar launches — to the planned Lunar Gateway only. A lunar launchpad will require extensive infrastructure development.

In summary, the apparent ease of extracting water ice from the lunar poles belies a complex infrastructure required to achieve it. The costs of infrastructure installation will negate the cost savings rationale for in-situ resource utilization.

Alternatives to extraction

There are more preferable options. Hydrogen reduction of ilmenite to yield iron metal, rutile and oxygen provides most of the advantages of exploiting water. Oxygen constitutes the lion’s share of the LH2/LOX mixture. It involves no great infrastructure: thermal power may be generated by modest-sized solar concentrators integrated into the processing units. Each unit can be deployed where it is required – there is no need for long traverses between sites of supply and demand.

Hence, we can achieve almost the same function through a different, more readily achievable route to in-situ resource utilization that is also sustainable by mining abundant ilmenite and other lunar minerals.

Let us not keep repeating the same unsustainable mistakes we have made on Earth — we have a chance to get it right as we spread into the solar system.

This article is republished from The Conversation, a nonprofit news site dedicated to sharing ideas from academic experts. It was written by: Alex Ellery, Carleton University.

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Alex Ellery does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

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Vikings Settled In North America As Early As 1021, Researchers Say – iHeartRadio

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New research has dated Viking ruins in Canada’s Newfoundland to 1021. While archeologists have known that Vikings had settled in North America hundreds of years before European explorers ventured across the Atlantic Ocean and reached the shores of North America, they had never been able to pinpoint exactly when they arrived.

new study published in Nature provides evidence that around 100 men and women settled at L’Anse aux Meadows in Newfoundland 1,000 years ago.

“This is the first time the date has been scientifically established,” said archaeologist Margot Kuitems, a researcher at the University of Groningen in the Netherlands and the study’s lead author.

“Previously, the date was based only on sagas — oral histories that were only written down in the 13th century, at least 200 years after the events they described took place,” she said.

In order to build their new settlement and repair their ships, the Vikings had to cut down trees in the area. The researchers noted that a burst of cosmic radiation, possibly from a solar storm, hit the Earth in the year 993. Evidence of the storm can be found in tree rings, and researchers used that as a starting date to count the rings on the felled trees. After examining three different pieces of wood, they determined all three were cut down in 1021 using metal tools.

Researchers believe that the Vikings only stayed there for between three and 13 years before they returned to Greenland. The study authors are planning to continue their work and determine exactly how long the Vikings were at L’Anse aux Meadows.

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