"chasing ice"

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www.spiegel.de/wissenschaft/natur/groenland-das-eis-wird-dunkler-a-1059131.html

www.youtube.com/watch?v=Mpjn-WLLCxE

eos.org/opinions/what-darkens-the-greenland-ice-sheet

www.livescience.com/48538-greenland-dark-ice-sheets-photo.html

www.planetexperts.com/greenland-ice-turning-black-thats-bad-news/


www.youtube.com/watch?v=CZQn4fbtsis

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www.youtube.com/watch?v=ONK6w_Kq2YU

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www.theguardian.com/world/2016/feb/13/150000-penguins-killed-after-giant-iceberg-renders-colony-landlocked

www.spiegel.de/wissenschaft/natur/antarktis-eisberg-droht-pinguine-auszurotten-a-1077261.html

journals.cambridge.org/action/displayAbstract?fromPage=online&aid=10171606&fulltextType=RA&fileId=S0954102015000644

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www.atlasobscura.com/articles/a-beautiful-look-at-antarcticas-harrowing-ice-runways?utm_source=facebook.com&utm_medium=atlas-page

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www.nbcnews.com/video/watch-glacier-ice-bridge-plunge-into-water-642113091744?cid=sm_fb

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www.independent.co.uk/environment/greenland-ice-sheet-early-melt-melting-april-record-climate-change-warm-a6984136.html

www.spiegel.de/wissenschaft/technik/groenlands-eis-taut-dieses-jahr-besonders-frueh-a-1087394.html

abcnews.go.com/Technology/wireStory/scientists-greenland-ice-sheet-melting-freakishly-early-38373482

Greenland's massive ice sheet this week started melting freakishly early thanks to a weather system that brought unseasonably warm temperatures and rain, scientists say.

While this record early melt is mostly from natural weather on top of overall global warming, scientists say they are concerned about what it means when the melt season kicks in this summer. This however could be temporary.

On Monday and Tuesday, about 12 percent of the ice sheet surface area — 656,000 square miles or 1.7 million square kilometers — showed signs of melting ice, according to Peter Langen, a climate scientist at the Danish Meteorological Institute. It smashed record for early melting by more than three weeks.

That's normal for late May not mid-April, Langen said.

Normally, no ice should be melting in Greenland at this time of year. Before now, the earliest Greenland had more than 10 percent surface area melting was on May 5, back in 1990. Even in 2012, when 97 percent of Greenland experienced melt, it didn't have such an early and extensive melt.

Langen said the amount of melt now is not the issue, timing is: "It's nothing for July, it's huge for April."

"It's disturbing," Langen said. "Something like this wipes out all kinds of records, you can't help but go this could be a sign of things we're going to see more often in the future."

What's causing this weeks' unusual melt is a weather system that is bringing warm temperatures to Greenland and funneling lots of warmer-than-normal rain up from the south, Langen said. The rain and the above freezing temperatures help melt the ice.

Greenland's capital, Nuuk, reached 62 degrees (16.6 degrees Celsius) on Monday, smashing the April record high temperature by 6.5 degrees. Inland at Kangerlussuaq, it was 64 degrees (17.8 degrees Celsius), warmer than St. Louis and San Francisco.

Langen and other scientists said this is part of a natural weather system, but man-made climate change has worsened this. Tom Mote of the University of Georgia said had this natural event happened 20 or 30 years ago it wouldn't have been as bad as it is now because the air is warmer overall and carries more rain that melts the ice faster.

"Things are getting more extreme and they're getting more common," said NASA ice scientist Walt Meier. "We're seeing that with Greenland and this is an indication of that."

"This kind of freakish warm spell is another piece in the puzzle," Meier said. "One freakish thing every once in a while you might expect. But we're getting these things more often and that's an indication of climate change."

Langen said the measurements are based on scores of observations from monitors on the ice fed into a computer simulation. NASA normally measures melt with a satellite, but there are problems with the instruments, Meier said. Still, Mote said the satellite, if correct, showed on Monday conditions similar to what Denmark is reporting.

Greenland ice sheet melting is one of the more visible and key signs of man-made global warming from the burning of fossil fuels because it is causing seas to rise, putting coastal areas at risk, Meier said.

If the entire Greenland ice sheet melted, which would take centuries, it could add 20 feet or more to global sea level, Meier said. But within the next century, Greenland ice melt alone could raise sea level by a couple feet, he said.

"The concern is things are moving faster than we thought," Meier said.

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www.theguardian.com/environment/2016/aug/16/alaska-town-shishmaref-vote-climate-change-relocation

peninsulaclarion.com/stories/072102/ala_072102alapm0020001.shtml#.V7Vgytfel4J

grist.org/article/alaska-native-village-votes-to-relocate-in-the-face-of-rising-sea-levels/

www.spiegel.de/wissenschaft/natur/alaska-dorf-shishmaref-stimmt-fuer-umzug-aufs-festland-a-1108211.html

www.theguardian.com/sport/2016/mar/24/iditarod-climate-change-sled-dogs-winter-alaska


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www.sciencealert.com/thousands-of-strange-blue-lakes-are-appearing-in-antarctica-and-it-s-very-bad-news

Thousands of strange blue lakes are appearing in Antarctica, and it’s very bad news

Uh oh.
BEC CREW
22 AUG 2016

Scientists have confirmed that thousands of pristine blue lakes have appeared on the ice sheets of East Antarctica, and it’s got them very worried.

The problem? They’ve seen this kind of thing happen before. Greenland’s ice sheet has been disintegrating rapidly, losing a whopping 1 trillion tonnes of ice between 2011 and 2014, and research suggests it’s because of these lakes.

A team of UK researchers has analysed hundreds of satellite images and meteorological data taken of the Langhovde Glacier in East Antarctica, and found for the first time that between 2000 and 2013, nearly 8,000 of these lakes had formed.

Some of these formations, known as supraglacial - or meltwater - lakes, appear to be draining into the floating ice below, which could have serious consequences for the stability of the entire ice shelf.

Ice shelves are thick, floating slabs of ice that form where a glacier or masses of ice flow down a coastline, whereas an ice sheet is a massive chunk of glacier ice covering an area of land greater than 50,000 square kilometres (20,000 square miles).

What’s strange about this news is the fact that researchers had assumed that East Antarctica was fairly impervious to rising climate and ocean temperatures, and have instead been focussing their efforts on investigating the Antarctic Peninsula.

The Antarctic Peninsula is the northernmost part of the mainland of Antarctica, and has shown signs of rapid atmospheric and ocean warming in recent years.

The disintegration of the East Antarctic ice sheet, on the other hand, has been more subtle, and now researchers are concerned that our lack of knowledge on how supraglacial lakes are affecting it will impact our ability to predict the consequences.

"[East Antarctic is] the part of the continent where people have for quite a long time assumed that it’s relatively stable," one of the team, glaciologist Stewart Jamieson from Durham University, told Chris Mooney at The Washington Post.

"There’s not a huge amount of change, it’s very, very cold, and so, it’s only very recently that the first supraglacial lakes, on top of the ice, were identified."

As Mooney explains, as the air temperatures rise during the summer months, these supraglacial lakes form on the surface of the ice sheets, and on the slender glaciers that stretch out into the ocean.

These lakes don’t last long - they either disappear through refreezing (the best option), drain vertically through the floating ice, or overflow into rivers on the surface that drain into the ice below.

These last two options have been shown in Greenland’s case to eat away at and weaken the structure of the ice sheets and ice shelves, hastening their own disintegration.

"Sometimes, researchers have even been able to document fresh water flowing outward directly into the sea from the base of a glacier," Mooney says.

"That injection of cold fresh water into salty water can then create tornado-like underwater flow patterns at the submerged glacier front that cause further ice loss."

So why did thousands of these things suddenly appear in East Antarctica over the course of just three years? You guessed it - climate change.

The team found that over the 13-year period they studied, the warmest (Southern Hemisphere) summer was between 2012 and 2013, with a total of 37 "positive degree days", and a mean daily surface air temperature of 0.8 degrees Celsius in January.

For comparison, the 2007/2008 summer had just five positive degree days and a mean daily surface air temperature of -1.8 degrees Celsius in January.

During this 2012/2013 summer, Langhovde’s glacier surface experienced 36 percent more new lakes and surface channels overspilling than ever before.

"What we find is that the appearance of these lakes, unsurprisingly, is correlated directly with the air temperature in the region, and so the maximum number of lakes, and the total area of the lakes, as well as the depth of the lakes, all of these things peak when the air temperatures peak," Jamieson told The Washington Post.

The researchers aren't ready to call this the beginning of the end of the East Antarctic ice sheet just yet, saying that if things stayed as they are, we wouldn't have much to worry about.

But with July 2016 being confirmed as the world's hottest month since records began, and the 10th consecutive month of record-breaking heat across the globe, historic levels of rising temperatures are something we're going to have to get used to, and that could mean more and more supraglacial lakes.

"The size of the lakes ... are probably not big enough to do much at present, but if climate warming continues in the future, we can only expect the size and number of these lakes to increase. So that’s what we’re looking at," Jamieson says.

At least some corals will be happy.

The study has been published in Geophysical Research Letters.

www.washingtonpost.com/news/energy-environment/wp/2016/08/17/these-stunning-blue-lakes-just-gave-us-a-new-reason-to-worry-about-antarctica/?utm_term=.2c59cca109dd

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www.theguardian.com/environment/2016/nov/25/arctic-ice-melt-trigger-uncontrollable-climate-change-global-level?CMP=fb_gu

Arctic ice melt could trigger uncontrollable climate change at global level

Scientists warn increasingly rapid melting could trigger polar ‘tipping points’ with catastrophic consequences felt as far away as the Indian Ocean

How melting Arctic ice could cause uncontrollable climate change

Fiona Harvey

Friday 25 November 2016 05.01 GMT
Last modified on Friday 25 November 2016 15.38 GMT


Arctic scientists have warned that the increasingly rapid melting of the ice cap risks triggering 19 “tipping points” in the region that could have catastrophic consequences around the globe.

The Arctic Resilience Report found that the effects of Arctic warming could be felt as far away as the Indian Ocean, in a stark warning that changes in the region could cause uncontrollable climate change at a global level.

Temperatures in the Arctic are currently about 20C above what would be expected for the time of year, which scientists describe as “off the charts”. Sea ice is at the lowest extent ever recorded for the time of year.

“The warning signals are getting louder,” said Marcus Carson of the Stockholm Environment Institute and one of the lead authors of the report. “[These developments] also make the potential for triggering [tipping points] and feedback loops much larger.”

Climate tipping points occur when a natural system, such as the polar ice cap, undergoes sudden or overwhelming change that has a profound effect on surrounding ecosystems, often irreversible.

In the Arctic, the tipping points identified in the new report, published on Friday, include: growth in vegetation on tundra, which replaces reflective snow and ice with darker vegetation, thus absorbing more heat; higher releases of methane, a potent greenhouse gas, from the tundra as it warms; shifts in snow distribution that warm the ocean, resulting in altered climate patterns as far away as Asia, where the monsoon could be effected; and the collapse of some key Arctic fisheries, with knock-on effects on ocean ecosystems around the globe.

The research, compiled by 11 organisations including the Arctic Council and six universities, comes at a critical time, not only because of the current Arctic temperature rises but in political terms.

Aides to the US president-elect, Donald Trump, this week unveiled plans to remove the budget for climate change science currently used by Nasa and other US federal agencies for projects such as examining Arctic changes, and to spend it instead on space exploration.

“That would be a huge mistake,” said Carson, noting that much more research needs to be done on polar tipping points before we can understand the true dangers, let alone hope to tackle them. “It would be like ripping out the aeroplane’s cockpit instruments while you are in mid-flight.”
Arctic sea ice shrinks to second lowest level ever recorded
Read more

He added: “These are very serious problems, very serious changes are happening, but they are still poorly understood. We need more research to understand them. A lot of the major science is done by the US.”

Scientists have speculated for some years that so-called feedback mechanisms – by which the warming of one area or type of landscape has knock-on effects for whole ecosystems – could suddenly take hold and change the dynamics of Arctic ice melting from a relatively slow to a fast-moving phenomenon with unpredictable and potentially irreversible consequences for global warming. For instance, when sea ice shrinks it leaves areas of dark ocean that absorb more heat than the reflective ice, which in turn causes further shrinkage, and so on in a spiral.

The Arctic ice cap helps to cool sea and air temperatures, by reflecting much of the sun’s radiation back into space, and acting as a global cooler when winds and ocean currents swirl over and under it. It has long been known to play a key part of the global climate system, but the difficulty and expense of close monitoring have meant that scientists have only in recent years been able to make detailed assessments.

The report, billed as the first comprehensive study of ecosystems and societies in the region, found: “The potential effects of Arctic regime shifts [or tipping points] on the rest of the world are substantial, yet poorly understood. Human-driven climate change greatly increases the risk of Arctic regime shifts, so reducing global greenhouse gas emissions is crucial to reducing this risk.”


The authors also warned that people living in and near the Arctic would be badly affected, and called for communities to be provided with equipment and skills to survive. They took evidence from a variety of settlements in the region, finding many signs of stark changes already under way.

Joel Clement, co-chair of the project and director of the office of policy analysis at the US Department of the Interior, said: “This groundbreaking report is an unprecedented effort to gain insight from what is happening on the ground. The findings are foundational to a more informed, coordinated response to building resilience across the region.”

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www.zeit.de/wissen/umwelt/2016-11/klimawandel-meereis-arktis-antarktis-polarforscher/komplettansicht

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www.alternet.org/environment/how-disappearing-arctic-ice-could-lead-global-climate-catastrophe

www.planetextinction.com/planet_extinction_greenland.htm

www.spiegel.de/wissenschaft/natur/extremer-meeresspiegelanstieg-kann-groenland-komplett-abschmelzen-a-1124872.html


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www.iflscience.com/environment/when-antarctic-iceberg-size-country-breaks-away-what-happens-next/