Green Icebergs

Scientists May Soon Solve Century-Old Mystery of Green Icebergs

Most icebergs appear white or blue when floating in seawater, but since the early 1900s explorers and sailors have reported seeing peculiar green icebergs in certain parts of Antarctica.

The strange green icebergs have always baffled scientists, but now a new study suggests iron oxides in rock dust from Antarctica’s mainland are turning some icebergs green.

According to the study published in the Journal of Geophysical Research: Oceansmarine ice varies in color due to the “abundance of foreign constituents in the seawater,” particularly iron-oxide materials. Researchers formulated the theory after they detected “large amounts of iron” during a 2016 research trip to the Amery Ice Shelf in East Antarctica.

“Previously, dissolved organic carbon (DOC) had been proposed to be responsible for the green color,” authors Stephen Warren, Collin Roesler, Richard Brandt, and Mark Curran explained in the paper. “Subsequent measurements of low DOC values in green icebergs, together with the recent finding of large concentrations of iron in marine ice from the Amery Ice Shelf, suggest that the color of green icebergs is caused more by iron‐oxide minerals than by DOC.”

Iron is a key nutrient for phytoplankton, microscopic plants that form the base of the marine food web. But iron is scarce in many areas of the ocean. If the researchers’ theory is confirmed, it would mean green icebergs are ferrying precious iron from Antarctica’s mainland to the open sea when they break off, providing this key nutrient to the organisms that support nearly all marine life.

“It’s like taking a package to the post office,” Warren, a glaciologist at the University of Washington and lead author of the study, said in a statement. “The iceberg can deliver this iron out into the ocean far away, and then melt and deliver it to the phytoplankton that can use it as a nutrient.”

Warren had been studying the green iceberg phenomenon since 1988. He analyzed samples taken from a green iceberg near the Amery Ice Shelf and found they were not made from regular glacier ice, but from marine ice, which is ocean water frozen to the underside of an overhanging ice shelf.

Seawater sometimes freezes to the underside of ice shelves, creating a layer of what’s called marine ice. (Credit: AGU)

When an oceanographer testing an ice core from Amery Ice Shelf found marine ice near the bottom of the core had nearly 500 times more iron than the glacial ice above, Warren began to suspect iron oxides in the marine ice could be turning blue ice green.

Warren believes iron oxides in “glacial flour,” a powder created when glaciers grind against bedrock, from rocks on Antarctica’s mainland are responsible for creating the stunning emerald icebergs. He now wants to to sample icebergs of different colors for their iron content and light-reflecting properties (icebergs are usually blue in color, because the ice absorbs more red light than blue light).

If their theory proves correct, green icebergs could be more important than scientists thought.

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UK Antarctic meteorite hunt bags large haul

Space rocks!

The first British-led expedition to gather meteorites in the Antarctic has returned with a haul of 36 space rocks.

Manchester University’s Dr Katherine Joy was dropped in the deep field with British Antarctic Survey guide Julie Baum for four weeks.

The pair spent their days near the Shackleton mountains running across the ice sheet in skidoos looking for out-of-place objects.

The meteorites ranged from tiny flecks to some that were as big as a melon.

Some two-thirds of the meteorites in the world’s collections have been picked up in the Antarctic. It’s the contrast of black on white that makes the continent such a productive hunting ground.

“As soon as you spot a black rock you know. You dart towards it and your heart picks up a beat,” Dr Joy told BBC News.

“They look black because they’re burnt up as they come down through Earth’s atmosphere. They have a very characteristic exterior colour, and they have a kind of cracked surface where that exterior has expanded and contracted during the violent atmospheric entry.”

Read the rest

Scientists Discover Hidden ‘Supercolony’ of 1.5 Million Penguins After Tracking Poop From Space

Scientist: We are running out of penguins due to climate change.

Other Scientist: Nope.

Imagine if your community pooped so much it was visible from space. A supercolony of 1.5 million Antarctic Adélie penguins has bragging rights to this achievement, after scientists discovered the birds thanks to satellite images of their pink guano.

Despite its large population, the colony has managed to remain off the maps since it first took roost on the Danger Islands some 3,000 years ago. The archipelago, which is named for the dangerous ice cover that surrounds it even in the summer, sits near the tip of the Antarctic Peninsula, and has barely been explored.

But when scientists developed an algorithm for detecting penguin guano in NASA Landsat imagery, the Danger Islands showed up as an untapped hotspot.

“We thought that we knew where all the penguin colonies were,” said Heather Lynch, a Stony Brook University ecologist, at a news conference during the American Geophysical Union (AGU) meeting last week. “But in fact, this small archipelago, that measures only 15 kilometers from one end to the other, [has] more Adélie penguins than the entire rest of the Antarctic peninsula combined.

Big increase is Antarctic Snowfall

“When scientists looked at Antarctic snowfall over the past 200 years they found a “significant” increase, up to 10%.

In the decade 2001-2010, some 272 billion tons more snow fell on Antarctica per year compared with the decade 1801-1810.

This extra amount of snow is equivalent to twice the water volume of the Dead Sea, on a per year basis.”

https://wattsupwiththat.com/2018/04/09/big-increase-is-antarctic-snowfall-helps-to-prevent-sea-level-rise/

 

More Wind – Less Wind = Climate BS

Oh No! Thank god we have “experts”.

“With the potential to cause sea levels to rise by more than 11 feet and unleash the ice of the East Antarctic Ice Sheet, the massive Totten Glacier has come to be known as the ‘sleeping giant.’

And now, scientists have discovered that strong winds over the Southern Ocean could be causing it to wake up.

A new study has found that East Antarctica’s largest glacier is melting from beneath, as winds transport warm water to the ice – and, these winds are expected to intensify with climate change, the experts warn.  

http://www.dailymail.co.uk/sciencetech/article-5047383/Strong-winds-causing-Totten-glacier-melt.html

 

Ooops!

 

Wind speeds around the world seem to be decreasing in a phenomenon known as ‘stilling’ and European scientists are hoping to find out why.”

https://phys.org/news/2017-10-stilling-global.html#jCp

 

Antarctic Ozone Depletion Caused By Volcano

Erebus Volcano and Ozone Depletion

“Erebus volcano eruptions are of the Strombolian type, which volcanic ejecta and gases are known to reach heights of 1–2 km above the volcano summit and, therefore, cannot directly reach the stratosphere (Boichu et al., 2010, 2011; Dibble et al., 2008). However, according to aircraft observations in 1989 at a height of 8 km over Antarctica, the detected aerosol particles were identified as volcanic ejecta of Erebus (Chuan, 1994). Together with HCl and H2SO4 high concentrations in the Antarctic stratosphere, it is indicative of delivery mechanisms of Erebus volcanic gases into the Antarctic stratosphere.

Erebus volcano gas emissions can ascend to the Antarctic stratosphere via high-latitude cyclones which are coupled to the stratospheric polar vortex in cold seasons.”

“Thus, for more than 40 years, Erebus volcano, which activity restarted in 1972, has been a natural source of chemical species destroying the Antarctic ozone. The extremely high Erebus volcanic activity in the early 1980s definitely made a major contribution to the increase of the ozone hole along with man-made chlorofluorocarbons. Regular observations of Erebus volcano gas emissions can help to predict the total ozone content dynamics and, therefore, the ozone hole area.”

 

http://www.sciencedirect.com/science/article/pii/S1352231015304246

PDO AMO Arctic Antarctic

The graphs start from 1950 to show a full 66 year cycle of the PDO and AMO.

I’m graphing anomalies from the mean for all. Sea Ice is in millions of sq km.

PDO versus Arctic Extent  – note that the satellite record for sea ice starts at peak of PDO

AMO versus Antarctic Extent

Everything