Sleeping at WAIS Divide

We sleep in tents. They are called “Arctic Ovens.” They are very warm when the sun is out, but the sun hasn’t been out much this last week.

Going to sleep can be a bit cold.  I go to sleep at about the coldest part of the day, 2 AM.  The outside temperature is something below zero. The inside temperature is unknown – the “inside” thermometer only goes down to freezing.  Now, every night when I go to bed, it reads LL – which is just as well, I don’t want to know the actual temperature.

The Arctic Ovens are actually quite spacious – 8×8. I have it arranged as sleeping bag on one side, all of my crap covering the rest. 

I have a fair bit of stuff. Warm layers, more warm layers, and of course, a Penguin Onesie. 

Getting into my sleeping bag is actually a bit of complicated affair.  First, I changed into my sleeping clothes – sleeping bag socks and long underwear.  These are normally cold because I leave them in my tent instead of taking them into the heated structures during the day.

Then I climb into my sleeping bag liner, the red fleece thing. This keeps me warm inside my GIANT sleeping bag. I was given a large sleeping bag, good for a 6’6” guy, much too big for me. So I pack extra fleece clothing at the bottom to minimize the air space. I then lay the blanket over the top of the sleeping bag.

I spend the next five minutes trying to figure out how to get both the zipper of the fleece liner and sleeping bag to be up at the same time. Then I put on a hat, lay my head on my pillow, and try to cinch the sleeping bag so that cold air doesn’t sweep in around my neck.  If it’s really cold, I tie a wool sweater around my neck like a scarf. It may feel like I’m being strangled every time I move slightly, but at least I’m warmer.

After falling asleep, I slowly shed layers throughout the night, as the outside and inside temperature warm up.  I sleep a lot here – I’m in my tent at least 10 hours a night.  It’s always warmer in the morning, typically 40 or 50 degrees. Balmy.

And that’s sleeping at WAIS.  Overall, the plushest snow camping I’ve ever done!  

Sleigh Ride to the South Pole!

I had another amazing opportunity — To travel by C-130 to the South Pole.  Since it was a fuel drop mission, we flew to the south pole, had 30 minutes to explore the bottom of the world, and then flew back to McMurdo.  The 6 hour flight was well worth the 30 minutes on the ground.  The flight itself was gorgeous.  There are a couple of windows on the C-130 so we could see and photograph the sites.

The views were phenomenal!  Since my last aerial slide show had good feedback, I will post another slide show from this flight in a couple of days.

We landed on a vast expanse of white.  It was cold and windy.  But the excitement of the experience made the weather not seem so bad.  Unlike McMurdo, the skiway is very close to the South Pole Base.  The main station is pictured below.  It is much smaller than McMurdo!

We walked past the ceremonial pole, located in front of South Pole Station, to see the Geographic South Pole.  Each year the winter over crew designs and creates the pole marker for the geographic pole at 90 degrees south.  On January 1st of each year, there is a ceremony to place the new marker.  The marker has to be placed in a new position every year because it is on an ice sheet!  The ice sheet moves approximately 10 meters per year towards the Weddell sea so the position of the station and marker shifts in relation to the geographic south pole.

This year, they celebrated the 100th anniversary of Amundsen’s arrival at the pole and 100 years of exploration.  It was created in the shape of a sextant – an instrument used for navigation by early explorers.  The 47 degrees on the Sextant represents the 47 winterovers at the pole last winter.

Then we rushed to the more well recognized, Ceremonial South Pole.  The position of this marker never changes in relation to the station.  We walked around the world in less than 30 minutes!

And a self portrait of Christine and I:

And then, our time was up.  I had time to give hugs to friends at the Pole.  Then we boarded the plane back to McMurdo.

WAIS Divide: Ice and Ash

Deep in the ice sheet, the ice is very clear – there are almost no bubbles in it.  By about 1500 meters, the pressure in the ice is so great that air in the bubbles gets forced into the ice matrix into something called clathrates.  It’s really fun to look at such a pure substance. It’s hard (for me at least) to capture it with a camera.

There’s only a limited window to see the ice this clear because once the ice is at the surface, the pressure has been relieved, and the bubbles start to reappear. When I see this ice again in Denver this summer, it will not be nearly as clear.

Most of the ice cores are perfectly clear except for the breaks that occur every three meters. However, we have gotten to see a lot of ash layers. West Antarctica is volcanically active – Ross Island, where McMurdo is, is a volcanic island with the very active Mt. Erebus just a few miles away.  That volcanism leaves beautiful layers in the ice.

This layer is from a little over 3000 meters deep. The ash is about ~45,000 years old and is still amazingly preserved.  We jokingly call it “skua poop.”  It was probably a very thick ash layer at one point because the ice has thinned ~20x (that is, a layer that started 20 cm thick is now 1 cm thick).

We just got a new ash layer, so I’m adding photos of it too! It’s probably around 60,000 years old.

WAIS Divide: The Drill

** We have set a US Ice Core Drilling Depth Record. The previous record was 3053.6 m in Greenland. We past that depth at 1 AM on Jan. 18! **

I answered a question about the drill a couple of days ago, and I thought it deserved a more complete post along with some pictures.

We are using the DISC Drill – Deep Ice Sheet Coring Drill. It was designed about 10 years ago for this project.  The drill is about 15 meters long.

It’s hard to get the entire drill in one photo, so I needed two.  Something  you need to know about drilling ice cores is that the boreholes (that the drill travels through) are fluid filled starting about 100 meters below the surface. The fluid is necessary to keep the borehole from closing in on itself. If the hole were left dry, the ice would flow to the borehole (an area of low pressure) causing it to close.

There are four main sections to the drill from bottom to top:

Core Barrel – The core barrel is the part of the drill on the bottom which does the cutting and collects the core.  You can see the ice core inside the core barrel. For scale, the ice core has the same diameter as a CD. There are four cutters on the bottom of the drill barrel which spin around, shaving away the ice between the core and ice sheet. The core barrel can fit about 3 meters of ice per run.

To get the core back up to the surface, the bottom has to be broken away from the ice below it. To do this, four “core dogs” are pushed into the core at the bottom. These are the four metal pieces that you can see sticking into the core. These hold the ice core as the drill is raised, causing it to break off from the ice below.

This is the longest section of the drill. The chip screens collect the ice that gets shaved away by the cutter head. That ice has to be removed so that you don’t keep drilling the same chips over and over again. The DISC drill gets the chips up and away from the cutter heads by pumping the drilling fluid through the chips screens. The chips are moved with the fluid and get trapped. 

The pump is the curved part just above the chip screen. This is what pumps the chip-filled fluid up through the screens. Above that is the motor which turns the drill. And further above is the instrument section, which has all of the electronics to control the drill.  Most of the electronics are actually in the drill itself rather than being up in the control room.  The core barrel, chips screens, and the motor, pump and instrument section all spin.

The anti-torque is the fancy name for what keeps the drill in place in the borehole. If you look closely, you can see three pieces of bowed metal (the fourth is hidden). These press against the borehole wall, holding the top of the drill in place and allowing the cutter head to cut rather than just spin in circles.

So there are the main portions of the drill. One last part I need to mention is the cable.

The cable is not only what lowers and raises the drill, but it also runs the power and communication channels down to the drill.  You can see the cable is not wrapped cleanly in this photo. This caused about an hour delay, all because one little screw on the winch became loose.

In about 20 minutes, WAIS Divide will be the second deepest ice core ever drilled.  I’m about to head down to the arch to see it come through.  Pretty exciting – 3271.2 m

More on ice cores in a future post!

WAIS Divide: Going to the Bathroom

I thought some of you might be interested in how we go to the bathroom here on the West Antarctic Ice Sheet.  Well, here you go. If you’re about to eat, you may want to wait.

We have three “bathrooms” – one in each of the three main parts of camps – Town, Tent City, and the Arch.

Each bathroom has two parts: pee flags and outhouses.

The pee flag has a snow block wall built around it. This is party for privacy, but also for wind. A strong wind in negative temperatures can cause real problems!

As you can see, there is a large piece of plywood surrounding the hole. It prevents the snow from crumbling in and creating a pee pit.

This is really pretty similar to any other outhouse, except the seats are made of foam so you don’t freeze to it (and so it doesn’t hold much cold).

There is artwork and poetry in the outhouses.

The poetry might get its own post later, but much of it isn’t appropriate for a general audience. 

There are two major differences between these outhouses and your typical National Forest Campground ones. First, they don’t smell much because everything stays frozen. Second, you have to watch out for “pinnacles of poo.” You can imagine what those are – I’ll spare you the photo.

Flying Over The Transantarctic Mountains

Earlier this week, I had an amazing opportunity to fly in a twin otter plane over the Royal Society range of the Transantarctic mountains.  The glaciers, mountains and rock formations were gorgeous — the best views I have ever seen!!  I thought I would share the photos I took on the flight with you.  I have placed them in time order so you can see the constantly changing landscape.

The slideshow can be slowed down by moving your cursor over the picture, pushing stop and using the arrows to navigate.  Enjoy!

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Ice From the Air

Jessie posted some photos of her flight in a few months ago, but I thought it was time for some more. And I’ll try to give a little glaciology commentary (I just can’t resist).

It is incredibly cool to be allowed into the cockpit of an airplane. I felt like I was seven again and being invited up to the front. The only thing missing was the wings.

This was our first ice sighting. An iceberg is a chunk of glacier ice that flowed into the ocean and calved (broke) off.  Exciting, but there was lots more ice to come.

The sea ice is in the foreground. The glacier ice is the white in the distance. Sea ice is ocean water that has frozen. It is different from an “ice shelf” which is glacier ice that formed from snow and flowed into the ocean. Ice shelves are what make icebergs.

This is a picture of an ice tongue surrounded be sea ice. An ice tongue is just an ice shelf with a shape like a tongue.

You can trace the direction the glaciers are flowing in this picture.  Just to the right of the engine, there is a crevasse field where a nunatak (rock island) is projecting and the ice cannot flow smoothly around.

Icebreaker

The scene is changing around McMurdo as the summer winds down and we prepare for the next winter and summer season.  The icebreaker has arrived!  Which signals the start of base resupply.  With no flights into or out of McMurdo from March through August, the base has to be fully restocked with food, supplies and fuel. 

A photo taken and compiled by Jordan Watson captures the change in scenery perfectly.

The top picture shows the ice runway as it looked when I landed at the start of the season.  The bottom photo, taken from the same location, shows the Nathaniel B Palmer research vessel.  The runway is now water!!

It took a couple of days for the Oden icebreaker to arrive at the ice pier after it was seen on the horizon from hut point.  Even the penguin was anxiously awaiting its arrival.

The Oden is a icebreaker research vessel out of Sweden that was built in 1988.  The front of the boat is flat (rather than coming to a point), which allows the boat to ride up onto the ice to break the ice apart.  The NSF has chartered the Oden from the Swedish Maritime Organization to break apart the ice in front of McMurdo for six years (2006-2012).  It docked at our newly built ice pier.  The old pier is in the background and is waiting for wind to blow it away. 

The Nathaniel B. Palmer, a 94 meter ice-capable vessel, followed the Oden in to port.  It was built in Louisiana and is capable of breaking 3 feet of ice at 30 knots.  It would not have been able to break through the channel like the Oden did.  I had the opportunity to tour this gorgeous research vessel.  It just left on an 11 day research cruise and should be back to refuel next week.

We are now awaiting the arrival of the cargo vessel.  It is arriving later than expected.  Everyone is gearing up for a busy ship offload. 

Shoveling Snow For Science

Digging snow pits provides an interesting look at the ice sheet.  These photos were taken in a backlit snow pit.  Two snow pits were dug with a thin wall between them. They were a little over 2 m deep.  The deep blue light comes from backlighting the snow pit wall. 

You cover the first snow pit, the one you walk down into, with plywood. The second snow pit is left uncovered. This allows the light to travel through the snow pit wall into the dark snow pit that you’re standing in. 

What pops out is all the different layers in the snow.  You can see the history of snow being deposited on the ice sheet.

In the photo above, I’m pointing to what is most likely last year’s summer surface. There are bigger snow crystals which get formed by the strong temperature gradients at the surface.  The thin dark layers are likely wind crusts deposited during the storms of winter. 

All of this snow gets compressed into ice.  It snows about 70 cm a year here, which compresses down to about 20 cm of ice per year. These “annual layers” are one of the primary ways we date the ice core. From the surface to 1950 meters depth, I’ve counted 11622 years (with an uncertainty of about 1%).



Why WAIS Divide? Part 1

Antarctica is one of the few spots in the world dedicated to research. Jessie has done a great job explaining many of the research projects happening on the continent.  I’m going to try to explain why I am out here at the West Antarctic Ice Sheet (WAIS) Divide drilling an ice core.

We’re near an ice divide, which means ice flows away in two (or more) directions.  WAIS Divide has ice flow to the Ross Sea on one side (towards McMurdo) and to the Amundsen Sea (towards the Antarctic Peninsula) on the other side.

We are here at WAIS Divide because it’s the best spot in the world to examine how temperature and carbon dioxide affect each other.  We are not here simply to look at Antarctica; we are here because only in Antarctica is this record preserved.  This is not the first ice core drilled, but it will help answer a fundamental question about our climate:

How do changes in temperature and carbon dioxide affect each other?

Ice cores can help answers this because they have two really important properties:

1. They trap samples of the past atmosphere in bubbles
2. They can be dated with great precision (each year can be counted for many thousands of years)

From ice cores drilled in Greenland, we know that temperature can change rapidly: 5 degrees C in a decade or so (go to the bottom if you’re interested in how we know what the temperature was in the past).  That’s much faster than what we’re experiencing today.  If the climate can change so rapidly without any human input, what will the current emission of carbon dioxide do? We are looking for information from the past to inform us about what the future holds.

When you hear “rapid climate change” this is what scientists are talking about.  But in Greenland, the carbon dioxide record is not preserved; too much dust is deposited in the snow which causes a chemical reaction altering the amount of carbon dioxide trapped in the bubbles.  Antarctica gets very little dust because there is much less land mass in the southern hemisphere than in the northern. And the carbon dioxide trapped in the bubbles does not get changed with time. 

Other ice cores in Antarctica give great records of carbon dioxide, but for much longer time periods.  The Dome Concordia Ice Core goes back ~750,000 years.  From this, we know temperature and carbon dioxide vary together. However, the relative timing of the changes is not known because the long length of time means that there is less precision. For instance, a data point may average conditions over a thousand years when we want to know what happened every hundred years. 

WAIS Divide is the best spot in the world to get a record of temperature and carbon dioxide changes for the past ~100,000 years. The age of the ice spans the many interesting rapid climate changes while also giving high precision dating to the changes in temperature and carbon dioxide.

I will keep posting additional blogs explaining more about the glaciology of this site (that’s what I do after all) and more about the climate questions we are trying to answer. Please post questions so I know what you are interested in.

 

*Temperature changes can be recorded in three ways:

1. The water isotopes in the ice. Oxygen typically has 8 protons and 8 neutrons (oxygen 16), but it can also have 18 protons and 10 netutrons (oxygen 18).  When the climate is colder, there is less oxygen 18 in the snow. This occurs because molecules move less when it’s colder (there’s less energy), so the heavier oxygen 18 falls out before it reaches the ice sheet. This is a complicated topic and 3 sentences do not do it justice. So don’t feel bad if it’s not making much sense – it’s because I can’t explain it well not being a chemist!

2. Borehole temperature profiles.  We can measure the temperature from the surface to the bed of the ice sheet by lowering a thermometer down a borehole (it’s fluid filled, but I’ll explain about that in a later post).  The temperature profile depends on three things: 1) the temperature at the surface; 2) the flow of the ice; and 3) the heat coming from the earth. With an ice flow model, you can reconstruct what the surface temperature must have been in the past.

3.  Mass and Temperature Dependent Fractionation of Stable Isotopes in Gases. Yeah, I’m frightened by the concept too, so I’m not even going to try to explain this one.