New focus for ice-shelf fears in East Antarctica

East Antarctica's massive ice sheet may be more exposed to global warming than long assumed, according to a study yesterday that shows how strong winds can erode ice shelves that help hold it in place.

There is enough frozen water sitting on top of the world's polar continent to raise sea level by dozens of metres and redraw the world map if it melts.

But understanding the dynamics of the region - which includes the much smaller West Antarctica ice sheet - has proven difficult.

Up to now, scientists have focused on the threat of West Antarctica.

Recent studies have suggested that climate change may already have condemned large chunks of its ice sheet to disintegration, whether on a time scale of centuries or millennia.

In contrast, ice covering East Antarctica was seen as far more stable, even gaining mass.

The floating, cliff-like ice shelves straddling land and ocean that prevent inland ice from slipping into the sea, it was thought, were solidly anchored.

That remains largely true. But a mysterious crater on the King Baudoin ice shelf, due south from the tip of Africa, prompted a team of researchers from the Netherlands, Belgium and Germany to challenge that assumption.

"Our research has shown that East Antarctica is also vulnerable to climate change," said Jan Lenaerts, lead author of the study and a researcher at Utrech

http://www.nzherald.co.nz/world/news/article.cfm?c_id=2&objectid=11766294

This stunning Antarctic lake is buried in ice. And that could be bad news

Atop the ice sheet covering the Arctic island of Greenland, you now see dramatic melting in the summer. It forms lakes, rivers and even dangerous "moulins" in the ice where rivers suddenly plunge into the thick ice sheet, carrying water deep below.

East Antarctica is supposed to be different. It is extremely remote and cold. It doesn't see such warm temperatures in the summer - yet - and so its ice tends to remain more pristine.

"Many people refer to East Antarctica as being too cold for significant melt," says Jan Lenaerts, a glaciologist with the Utrecht University in the Netherlands.

"I mean there's marginal melt in summer, but there's not a lot."

That's the common wisdom, at least, but it is challenged in a new study in Nature Climate Change, by Lenaerts and his colleagues from universities in the Netherlands, Belgium and Germany. They do so based on research they conducted atop the very large Roi Baudouin ice shelf in East Antarctica, which floats atop the ocean, and where they found a very Greenland-like situation in early 2016.

The researchers had traveled to investigate what had been described as a nearly 2-mile-wide "crater" in the shelf, glimpsed by satellite, which some sources believed had been caused by a meteorite. To the contrary, they found that it was a large, 10 foot deep, icy lake bed. In its center, meanwhile, were multiple rivers and three moulins that carried water deep down into the floating ice shelf.

And even this, perhaps, was not the most dramatic finding. The researchers also drilled through the ice and found what they called "englacial" lakes, sandwiched between the surface of the ice shelf and its base, which is in contact with the ocean beneath it. They found 55 lakes in total on or in the ice shelf, and a number of them were in this buried, englacial format.

This meant that the ice shelf is anything but solid - it had many large pockets of weakness throughout its structure, suggesting a greater potential vulnerability to collapse through a process called "hydrofracturing," especially if lake formation continues or increases. That's bad news because when ice shelves fall apart, the glacial ice behind them flows more rapidly to the ocean, raising sea levels.

But why was all this happening, and here?

http://www.nzherald.co.nz/world/news/article.cfm?c_id=2&objectid=11766187

Reindeer becoming smaller because of global warming, study says

Reindeer are shrinking on an Arctic island near the North Pole in a side-effect of climate change that has curbed winter food for the animals.

The average weight of adult reindeer on Svalbard, a chain of islands north of Norway, has fallen to 48kg from 55kg in the 1990s as part of sweeping changes to Arctic life as temperatures rise, experts say.

"Warmer summers are great for reindeer but winters are getting increasingly tough," Professor Steve Albon, an ecologist at the James Hutton Institute in Scotland who led the study with Norwegian researchers, said.

Less chilly winters mean that once-reliable snows fall more often as rain that can freeze into a sheet of ice, making it harder for the herbivores to reach plant food.

Some reindeer starve and females often give birth to stunted young. In summer, however, plants flourish in a food bonanza that ensures healthy females more likely to conceive in autumn - a pregnancy lasts about seven months.

http://www.nzherald.co.nz/world/news/article.cfm?c_id=2&objectid=11765284

There could be just two years left before the North Pole disappears

My 6-year-old asked me about Santa the other day. Luckily, it wasn't the moment where his innocence is shattered forever.

Instead, he was wondering how Santa was going, preparing for his annual voyage around the world, dispensing plastic junk from China to all the world's least-needy kids. (I added the last part, but you get the drift).

I painted the picture that my parents had passed on to me. I explained to him how the night is slowly descending across the North Pole at the moment, and by the time Santa sets off on his sleigh across the ice on Christmas Eve, it will be shrouded in continuous darkness, lit only by his Christmas candles, and one shiny red nose.

My son is very interested in fashion, and so we talked at length about Santa's warm red jacket. The sad thing that I didn't have the heart to tell my son is that, at the moment, Santa's big red jacket is probably too warm for Santa himself, even at the North Pole.

 

Santa is a fantasy but climate change is not, and it's started to do truly alarming things to the North Pole.

Over the past few weeks the temperature of the North Pole has been 22 degrees hotter than the average temperature for this time of year. That's not a typo. It's not 2.2 degrees hotter. It's 22 degrees Celsius hotter.

The reason it's such a huge difference is because even though night is now falling, the temperature around the poles is still getting hotter rather than colder. That's never happened before. What it means is that the gap between average temperature and this year's temperature is getting wider and wider by the day.

 

 http://www.nzherald.co.nz/world/news/article.cfm?c_id=2&objectid=11761907

Dead Zone' threat to fisheries in the Indian Ocean

A huge, mysterious 'dead zone' - 60,000 sq km devoid of oxygen and life - has been discovered in the Indian Ocean to the west of Australia.

Such zones have already been found off the coasts of North and South America, western Africa and the Arabian Sea.

But this is the first time one has been found encroaching into South-East Asia.

A study published in the science journal Nature Geoscience reveals a new 'dead zone' appears to be emerging in the Bay of Bengal, in waters extending from 100m to 400m in depth.

Dead zones are normally associated with a lack of oxygen and concentrations of microbes stripping the vital nutrient nitrogen out of the water.

In the case of the Bay of Bengal, no such nitrogen loss has yet been detecte
d.

And traces of oxygen have been found - at levels 10,000 times lower than normal air-saturated surface waters.

While this is less than is needed to support most life, it also impedes nitrogen-harvesting microbes.

http://www.nzherald.co.nz/world/news/article.cfm?c_id=2&objectid=11761624

Life on the ice: A glimpse of Antarctica

A field training instructor at Antarctica New Zealand's Scott Base has shared a video offering an insight into life on the frozen continent. 

Matt Windsor says his job generally involves providing training for scientists and providing safety support for their projects in the field.

His video chronicles an early summer trip to Granite Harbour, in which his job was to choose a route across the ice and identify and measure the cracks.

But in his downtime there was some fun to be had: his Antarctic leisure activities include kite skiing and snowmobiling.

http://www.nzherald.co.nz/environment/news/article.cfm?c_id=39&objectid=11760259

No, climate change won't kill us this decade

Guy McPherson, retired professor of conservation biology from the University of Arizona, has been on a speaking tour of New Zealand this month peddling a bleak message: we're going to push the planet's climate system over the edge and we've only got a decade to live.
A prominent New Zealand climate scientist sees no basis for that claim and says such alarmism, which has already generated a slew of scary headlines, is counter-productive to the crucial effort of combating the worst potential effects of climate change while we still can.

Science reporter Jamie Morton talked to James Renwick, a professor of physical geography at Victoria University of Wellington who served as a lead author on the last two IPCC reports and recently co-hosted a Royal Society of New Zealand-sponsored series of public talks on climate change.

What do you make of his claims? Is he misrepresenting climate science?

Misrepresenting - I'm not sure if that's quite the right word.
 
I've read stuff on his website and I've had a look at some of the papers that he's written and a lot of what he says is quite right and mainstream.

Where we seem to part company is this idea that [humans will be wiped out] in the next 10 years.

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