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Is Antarctica gaining ice?

What’s behind this story and why this publication is highly questionable.

By Bianca K.

Last week a newly published paper (http://www.ingentaconnect.com/content/igsoc/jog/pre-prints/content-ings_jog_15j071) stated that the Antarctic Ice Sheet is actually gaining and not loosing ice. A statement that is quite the opposite to pretty much every other scientific study on this topic.

No need to mention that this sparked a new debate and released a media storm.

Continue reading “Is Antarctica gaining ice?”

Mama Grizzly

By Kate Holland

An image often associated with the melting of the Arctic ice cap, is that of a polar bear standing on thin ice, exemplified in Figure 1.

060403_DomCNNL3R1
Figure 1: Special Report Global Warming.
From: Time

The melting of sea ice is forcing polar bears to spend more time inland. Venturing far from their normal habitat they are interacting and interbreeding with grizzly bears, resulting in grolar bears, pizzly bears or more fancifully known as polizzly bears (pictured in Figure 2).

Technically, the naming of hybrids should depend on the sex of the parents, where the father provides the first half of the species name and the mother provides the latter half. For example, a pizzly bear has a polar bear father and a mama grizzly. But I can imagine it would be far more difficult to determine the paternity/maternity of a hybrid species outside a zoo.

grolarbear
Figure 2: A Grolar Bear – or is it a Pizzly?
From: The Guardian

The first wild grolar was encountered back in 2006, as a hunting prize. The hunter was able to avoid jail time –-and a fine – when DNA testing by Wildlife Genetics International in British Columbia confirmed the beast was a hybrid of a polar and grizzly bear (the hunters $45,000 permit was only for bagging polar bears). Since then a number of these hybrid bears have been sighted in northern Canada.

Some might argue that interbreeding is a good solution for polar bears faced with climate change. While hybridization is not necessarily a bad thing, it’s the short time periods over which it occurs, that causes a significant drop in genetic diversity. This is damaging to both species and will more quickly push them to extinction.

Interbreeding could also be a potential risk for survival, as obviously, each bear has evolved to live in quite different ecosystems. The grizzly bear is not designed for long swims, but what if a pizzly still has a taste for seals?

Then there is the rest of the ecosystem to worry about – how does the grizzly bear ecosystem deal with a grolar bear? Will it hunt all year round or hibernate? Will the grolar bear be a super predator in its habitat and cause extinctions down the food web? Such an interesting animal could also become the target of hunting (or worse – cheesy horror movies [Polizzlynado anyone?]) as it is not yet protected by conservation laws. In order to protect both, the polar bears and the ecosystems, some out-there ‘conservationists’, have suggested moving the bears to the Antarctic.

Turn back the bears!

Perhaps such issues for many species, both old and new, wouldn’t be such a problem if WE reduced our impacts on the environment – but that’s a discussion for another day.

 

The A-factor

Akademik Shokalskiy stuck after weather conditions changed and sea ice closed down behind the vessel.
Akademik Shokalskiy stuck after weather conditions changed and sea ice closed down behind the vessel.

By Bianca

I just stumbled over a detailed media report about the Russian Akademik Shokalskiy that recently had to be rescued out of Antarctica’s sea ice, and have been reminded about our excursion to the continent.

Although I do agree that a lot went wrong on their expedition, and human failures played an important role, it has also be admitted that you simply can’t change the A-factor and you need to adapt to it as much as possible.

The A-factor simply stands for the Antarctic-factor and is a common saying under Antarctic expeditioners as the climate is so unpredictable and weather conditions can change quickly. Continue reading “The A-factor”

First days on the Antarctic continent

By Bianca,

After our arrival near Davis station we got flown out by a helicopter to catch our plane to Mawson. The Aurora can only park in the sea ice, around 3-4 km away from Davis station and usually people just walk over the sea ice. However, due to the delay we already had, people who weren’t staying at Davis got rushed out,

Icebergs in the sea ice in front of Davis station
Icebergs in the sea ice in front of Davis station

to fly 2,5 hours to Mawson. One of the reasons was the fantastic weather we have had these days, with a blue, sunny sky and almost no wind. Arrived at the station we got loaded with work, which was a sudden change to the lazy and relaxed life on the Aurora. After some more information and briefings we got our equipment and started our overnight field and survival training on the next day. We mainly got trained on how to survive in case of a sudden weather change and the risk of getting lost. Under really bad conditions you can miss your team colleague or the hut even when it’s just 20m beside you and finding shelter, without falling into a crevasse would be your main concern. We walked over the sea ice in Mawson bay, did some mapping and GPS reading exercises, drilled into the sea ice to check the thickness, exercised whiteout conditions by finding an object walking with a pillow case on our heads and carved our bed for the night into the snow. This night was an exercise to survive in an emergency just with your survival gear (warm clothes, map, compass and GPS, ice axe, sleeping bag and bivvy) by

Bivvying in the snow as part of the survival training
Bivvying in the snow as part of the survival training

quickly setting up a shallow hole where you can place your bivvy. The night was rather cold (ice formed inside the bivvy) and we were all happy when we went back to the station early on the next morning.

After arriving back at the station we had some breakfast, a shower and some more sleep before we started our day. We began to organise the food for our camping trip and the field equipment that will be required (a bit more luxury than the survival night). In the evening we were lucky to get a ride in one of the Hägglund (Hagg) with the chief of the station up to one of the mountain huts. That means going up the big Antarctic plateau, all just pure ice. We got an incredible view over the plateau, mountain ranges and the sea with its icebergs, and the thought about the fact that you were standing on

The Hägglund we used on our trip up the ice plateau. The front door got blown inside the Hagg by the katabatic winds and had to be repaired after our trip
The Hägglund we used on our trip up the ice plateau. The front door got blown inside the Hagg by the katabatic winds and had to be repaired after our trip

almost a kilometre of pure ice was, and still is, just unbelievable. After a couple of hours and a tea in the hut, we went back to the Hagg to go somewhere else…and learned why you have to be prepared for everything here in Antarctica. The Hagg didn’t start for any obvious reason and could not be fixed. Meanwhile the katabatic winds started to blow and within five minutes conditions changed from beautifully calm and mild to windy and freezing. Considering weather conditions and time (by then it was 9.30pm) the decision was made to stay in the hut.

Fortunately, it was a surprisingly comfortable night, with a real bed, a little kitchen and plenty of food (all kinds of food, as everything survives in the cold). On the next morning, after the loss of one of the Hagg doors due to the very strong katabatic wind and some more hours of trying to fix the Hagg we were successfully on our way back to the station.

On the following day we decided not to go anywhere, with the hope to finally sleep in our bed at the station. The weather has been really good again, although we had strong winds. Tomorrow we are likely to start our field work, if the weather doesn’t change we will fly out to set camp at Richardson Lake in Enderby Land and to set up our GPS stations (previous blog post).

View to the mountain ranges from Mt. Henderson
View to the mountain ranges from Mt. Henderson

Icebreaker versus sea ice

View from the bow of the Aurora
View from the bow of the Aurora

By Bianca

More than a week after the estimated arrival time we are still fighting our way through Antarctica’s very thick sea ice.

With ice conditions as tough as it can get (10 out of 10) our progress was more than slow and the outlook of arrival had been uncertain for a long time. New rumours started to spread daily, including that we would have to turn around and go back. Fortunately, that didn’t happen and by now we are close to Davis and actually just got told that we are likely to arrive tonight. Continue reading “Icebreaker versus sea ice”

Life on the Southern Ocean

The Aurora Australis docked in Hobart
The Aurora Australis docked in Hobart

By Bianca

We are now somewhere around 60 degrees South, heading along Antarctica’s sea ice coastline until we will start breaking through the ice somewhere near Davis station.

We started our journey on the Aurora Australis last Tuesday, already with a two hour delay, due to cargo, and a further delay has occurred due to strong westerly winds. As soon as we left the protecting shores of Tasmania we quickly learned what’s lying in front of us: the forties and fifties of the Southern Ocean, famous for their roughness. Out on the open ocean we immediately hit a stormy sea with swells up to 6 meters. Good thing we all went to bed and our bodies could get used to it during a night sleep. The next day things didn’t seem too bad.

Stormy weather on the Southern Ocean Image: British Antarctic Survey
Stormy weather on the Southern Ocean
Image: British Antarctic Survey

That however only lasted for a day until we hit another stormy weather front with waves up to 12 meters. That afternoon many of us didn’t feel too good and I think I figured out why. If the ship rolls left to right, which is quite normal, everything is fine. As soon as it starts rolling in all directions, i.e. forwards and backwards and up and down, that’s where you find most people in bed… Continue reading “Life on the Southern Ocean”

US Government Shutdown Claims Antarctica Field Season

By Evan

By the time this is posted, I hope that the US government shutdown is old news. Though I vowed to not read the news, something this big is hard to not hear about. Plus there is the fact that pretty much every government website, include those with geophysical and geological data, are completely shut down. Recently, I have been studying the tilting of large lakes due to post-glacial rebound, and a bunch of the data are on the NOAA website. Of course, when you go to website now, you get this:

noaa_shutdown

Unfortunately, most geophysical data are not considered to be necessary to protect lives, so they are down. I am very lucky that I downloaded the data that I needed before October 1st, otherwise I would be out of luck! Continue reading “US Government Shutdown Claims Antarctica Field Season”

And so the adventure begins…

The Aurora Australis on its way through the Antarctic sea ice.
The Aurora Australis on its way through the Antarctic sea ice.

By Bianca

By the time you read this post I will be already in Hobart to start my days early at 8.30am with some special training. Training to prepare us for life in one of the roughest places on Earth – Antarctica.

Despite spring slowly coming upon us, temperature will be well below freezing and weather conditions can change quickly from a blue sky to wipe-out conditions. All that and more is what we will be trained for at the Australian Antarctic Division in Kingston, Tasmania. Continue reading “And so the adventure begins…”

Chasing Ice

chasingBy Bianca

If you don’t believe in climate change, that’s okay. If you don’t believe scientists that climate change is real, that is okay too. But surely you will trust your own eyes…or will you?

That is how it begun for James Balog, an environmental photographer who started an assignment for National Geographic. Despite the fact that he has been sceptic about climate change, Balog committed to the task of capture images of our retreating glaciers and realised that the ice is disappearing at a breathtaking rate.

Chasing ice captures images you wouldn’t believe, if you hadn’t just seen it with your own eyes. The observations that have been made are a fact, simply observed by cameras, and reveal that the changes in our glaciers are tremendous. Continue reading “Chasing Ice”

Southern Hemisphere finally gets some credit

Part of the new WAIS ice core
Part of the new WAIS ice core

By Claire

A new ice core, drilled in West Antarctica suggests that the Southern Hemisphere, and not the Northern Hemisphere began warming first at the end of the last ice age, approximately 20,000 years ago.

Up until now, it was believed that deglaciation, at the end of the last glacial maximum, around 20,000 years ago was initiated by the Northern Hemisphere. Now, to anyone not involved in palaeoclimatology, you might be asking why it even matters, as long as things started to warm up. Understanding the drivers of deglaciation is important, as it provides us with an understanding of the way that climate works.

Most palaeoclimate stories call on the Northern Hemisphere, and in particular, the North Atlantic to initiate changes. The Southern Hemisphere, and Antarctica, has traditionally been viewed as a slave to the North Atlantic, only responding to changes, but not initiating them.  Continue reading “Southern Hemisphere finally gets some credit”

Temperature distribution in snow, firn and ice

firnBy Bianca

The temperature plays an important role in the behaviour of snow.

If it’s too warm the snow will just melt, but if it’s cold enough the snow turns into firn and eventually, into glacier ice. How long the transition from snow to ice takes strongly depends on the temperature.

The temperature that has occurred at the surface can take up to millennia to propagate through the glacier ice. That means temperature with depth can provide information on past variations in surface temperatures.

For my study of a firn compaction model, the temperature plays an important role in the speed of snow densification, and so we need to find a way to calculate the temperature distribution with depth. Continue reading “Temperature distribution in snow, firn and ice”

This week in climate science…

By Claire

Today, I wanted to share a series of snippets of new research that have emerged recently in the field of climate science. These stories have been all neatly compiled by DISCCRS in a weekly mail-out, which I recommend you go and subscribe to!

East Antarctic Ice Sheet Vulnerable to melt

Ancient sediments recovered off the coast of East Antarctica suggest that the ice sheet repeatedly melted back 3 to 5 million years ago, contributing to sea level rise
Ancient sediments recovered off the coast of East Antarctica suggest that the ice sheet repeatedly melted back 3 to 5 million years ago, contributing to sea level rise.

A new study published in Nature Geoscience has shown that in the past, the East Antarctic Ice Sheet has melted in response to warmer temperatures.

During the Pliocene, when global temperatures were 2 – 3 ºC warmer than present, the East Antarctic Ice Sheet retreated by as much as several hundred km inland. This new research is important, since it reveals that the East Antarctic Ice Sheet, which has been thought of as largely stable, does respond to changes in global temperature.

The Pliocene, 5.33–2.58 million years ago, represents a warm period in Earth’s climate history, where CO2 concentrations were around 400ppm. This period is often used as an analogue for future climate change, due to the similar CO2 concentrations between then and now. During the Pliocene, global temperatures were 2 – 3 ºC warmer, and sea level was around 25m higher than present.

Scientists drilled a sediment core off the coast of Adélie Land in East Antarctica, and analysed mud found within the core that was sourced from rocks currently found under the ice sheet. They concluded that  the only way so much mud could have been carried off to sea is if the ice sheet had retreated inland, eroding those rocks. Continue reading “This week in climate science…”

The journey of a snowflake – from snow to ice

GlacierBy Bianca

Have you heard about firn? No? Well, then maybe you don’t know as much about snow as you thought you do. At least that’s how it was for me before my research taught me more about glaciers.

IceCrystalsThe transition from snow to ice is easy. It all starts with the fall of single snowflakes in an environment cold enough for it not to melt – the first step in the formation of glacier ice. Once the snow settled it is exposed to changes and the little crystals of the fresh powder snow soon transforms to a different material due to climatic conditions.

Here we are, you just learned what firn represents. Continue reading “The journey of a snowflake – from snow to ice”

Antarctica – a general introduction

Bedrock map of Antarctica obtained by the BEDMAP2 project of the British Antarctic Survey
Bedrock map of Antarctica obtained by the BEDMAP2 project of the British Antarctic Survey

By Bianca

There have been quite a few articles about Antarctica by now, but none of them actually about Antarctica itself.

For most people the seventh continent is isolated from everything, and that is actually true. Located at the South Pole, it is not easily visited. Not only because it is at the South Pole, but also because we are talking about an area almost double the size of Australia, with 98% of its area covered in ice throughout the year.

But it’s not only the ice coverage that makes the continent so unpleasant and fascinating at the same time. With an average temperature of -49°C, Antarctica is the coldest place on Earth and holds, with -89°C at Vostok, the record for the lowest temperature ever recorded on our planet. Continue reading “Antarctica – a general introduction”

I’m sorry. Does my science offend you?

Nerilie cutting up an ice core from James Ross Island, 2008.
Nerilie cutting up an ice core from James Ross Island, 2008.

By Claire

Undoubtedly, the sexiest palaeoclimate proxy are ice cores. Most people have heard of them, most people believe them and they form an important foundation for our understanding of the natural variability of the Earth’s climate in the past.

Last week, a paper (published in Nature Geoscience) was written by our very own super scientist, Nerilie Abram, based on work she did while at the British Antarctic Survey. Nerilie and a team of scientists went to James Ross Island on the Antarctic Peninsula in 2008 to drill a 354 metre long ice core, spanning the last 1000 years.  Continue reading “I’m sorry. Does my science offend you?”

What collaboration can achieve

8d96f3ad79By Kelly

The perception that the ‘scientist’ sits in an ivory tower with no ability to communicate, let alone work, with others is one of the stereotypes the OnCirculation folks are trying to dismiss. The questions that earth scientists are trying to answer often need multiple teams from multiple countries, all coordinating and pooling resources to push our understanding further. As an example, did you know that we don’t know much about the topography and sea floor structure beneath the Southern Ocean? A recent press release by the Alfred Wegener Institute in Germany (that I discovered through the Earth Science Picture of the Day, see inset) describes how scientists from 30 research institutes across 15 countries collaborated to reduce 4.2 billion individual values into coherent digital maps of the Southern Ocean seafloor, or officially the International Bathymetric Chart of the Southern Ocean (IBCSO). Continue reading “What collaboration can achieve”

Antarctic sea ice increases due to climate change?

EREBUSCHANNEL630By Claire

Arctic sea ice has reached record low levels over the past few years due to climate change. A warming Earth has caused the extent of Arctic sea ice to decrease rapidly, suggesting that the Arctic will in fact be ice free within the next few decades.

In the Antarctic however, there’s a completely different story.

In recent years, the amount of sea ice surrounding Antarctica has expanded, reaching its maximum extent in 2012. How can we reconcile this picture with that of climate change? Well it turns out that they may be related after all.  Continue reading “Antarctic sea ice increases due to climate change?”

Not-so-Serious Sunday 41: More than just a sugar rush

By Kelly

As we wonder at the age of the universe it seems an appropriate time to look up at the night sky. Swedish photographer Göran Strand has been doing just that, and on March the 17th took 2464 images which you can see below as an extraordinarily beautiful time lapse. Sit back, digest your easter chocolate and marvel at the Aurora Borealis.

Continue reading “Not-so-Serious Sunday 41: More than just a sugar rush”

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