Tag Archives: Arctic

Nacreous Clouds!

The sun is on its way back and while we still have 3 weeks until the first sunrise each day is a little brighter than the last. New Year’s Eve dawned bright and clear with crisp stars and a few very special clouds on the horizon. At first they were startling neon pink, orange, and red. The first real sign of the sun in weeks and a beautiful contrast to the greens and blues of the night sky and aurora. As the day progressed the clouds grew in size, becoming clearly iridescent. With no insulating clouds overhead it was a chilly -60F ambient. The cold temperature, otherwise clear sky, low sun, and wavy iridescent features all pointed towards these clouds being Polar Stratospheric Clouds (aka PSCs or Nacreous Clouds).

These rare clouds are both terrible and beautiful. Forming in the stratosphere at 49,000-82,000ft and at temperatures below -100F they are composed of water, nitric acid and/or sulfuric acid. While beautiful, they are implicated in the depletion of stratospheric ozone – an important protective layer against harmful UV rays. According to TheOzoneHole.com:
PSCs were long regarded as curiosities and of no real consequence. However, Type I clouds are now known as sites of harmful destruction of stratospheric ozone over the Antarctic and Arctic. Their surfaces act as catalysts which convert more benign forms of man-made chlorine into active free radicals (for example ClO, chlorine monoxide). During the return of Spring sunlight these radicals destroy many ozone molecules in a series of chain reactions. Cloud formation is doubly harmful because it also removes gaseous nitric acid from the stratosphere which would otherwise combine with ClO to form less reactive forms of chlorine.”

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Bright neon clouds

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Polar Stratospheric Clouds – note their brightness, iridescence, and feathery/wavy structure

Measuring the ozone layer above us and the seasonal Arctic ozone hole is one of the many projects we support here at Summit. Every week the science techs launch a large balloon with a carefully calibrated instrument to measure ozone concentrations, as well as normal meteorological data (wind speed and direction, pressure, temperature, and humidity). The data is sent back via radio signal to the computer here at Summit.

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Winter

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After 4 days of weather delays the final turnover flight made it to Summit on November first. We unloaded several hundred pounds of fresh fruits and vegetables and various other resupply items then refueled the plane and loaded it up again with bags and passengers. The fall crew had finished their tour of duty and were heading home at last. The rest of the afternoon here on station was mostly spent settling into winter rooms and unpacking the fresh food and supplies.

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Freshies!

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The walk in refrigerator, aka “freshie shack,” stocked up for winter with fruits, vegetables, and dairy. It is cooled with outside air and warmed with heat reclaimed from the generators (a little electric heater on the far wall augments heating when temps get super cold)

Fresh food, aka “freshies”, is a big deal in the polar programs. A few stations (such as the South Pole) have green houses and are able to grow some fresh food, but most stations do not have such facilities. As with everything else, freshies must be shipped in from elsewhere. For McMurdo and field camps these come from New Zealand. Here in Greenland it depends on the season – in the summer (Apr-Aug) we get supplies via LC-130s with the NY Air National Guard out of New York state, so food and cargo can be shipped directly from the US. In the winter the hercs are deployed to Antarctica and so for the few crew turnover flights (Oct and Feb) we rely on chartered Twin Otters from Iceland.
Even a few minutes’ exposure to extremely cold temperatures will blacken banana skins and wilt lettuce so freshies from Iceland are sent up in styrofoam boxes to prevent freezing while being transported to and from the plane. We won’t get any flights until February so the freshies we get at the Oct turnover are it – We have to make them last as long as possible. Lettuce goes the fastest and there isn’t much we can do to preserve it so we try to eat that first. Cabbage, carrots, potatoes, beets, onions, and squash can last for months and can also be frozen. Even apples, bananas, and oranges will last weeks to months before we are forced to freeze them.

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Earth’s shadow to the North

Now that turnover is complete the station is relatively calm and quiet. We are stocked up with food and fuel and are looking good for the months ahead. Winter is a drawn out marathon compared to the frenetic summer season – there’s less overall to do, but everything takes longer. We won’t get another plane until late February 2017 so it’s just a matter of keeping ourselves alive, the station functioning, and our year-round scientific instruments, such as NOAA’s observatory and ICECAPS, in working order.

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An almost noon sun behind the Big House

It is now officially winter and it’s starting to feel like it. Today the sun rose at 9:13am and will set at 1:20pm, tomorrow it will be 9:22am and 1:12pm…the last sunrise will be on November 14th (www.timeanddate.com/summit). Temperatures are variable, but they are dropping lower and lower. Current conditions here are publicly available at: summitcamp.org/weather. On Thurs evening we reached a new low this season of -52F and with the cold and the dark come auroras!

Welcome to Winter!

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Hints of Hurricane at Summit Station

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Over the last 2 weeks we’ve had back to back wind storms with lots of drifting and blowing snow. On Wednesday, however, we got hit by the tail end of hurricane Nicole, by that time classified as a “post-tropical cyclone.” In a matter of hours our winds went from 20kn to over 60kn.

We follow similar weather criteria as the USAP: Condition 3 is visibility greater than 2000ft and wind-chill above -90F. Condition 2 is visibility between 2000ft and 200ft and/or wind-chill below -90F. And Condition 1 is the worst with visibility less than 200ft and/or wind-chill below -100F. When wind speeds exceed roughly 20knots snow is picked up reducing visibility and creating a white out. We’ve had a few cases of Con 2 recently with visibility under 2000ft, but I had yet to call on Con 1. Flag lines run between all the main buildings on station and during a storm all travel is monitored with radio calls including route and destination and check-in upon arrival. It can seem cumbersome at times, but it is also important to know where everyone is and that no one gets lost.

The day had started warm and a little windy with 20kn winds, but after midday they increased rapidly to 30kn then 40kn…finally hitting a peak sustained wind speed of 61kn gusting to 63kn! Unfortunately 53kn was the highest I saw on the station screen displaying current conditions.

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Current Conditions: -4F and 53kn winds

That was by far the highest wind speeds I’ve seen up here, though I doubt it broke any records. Winter and early spring storms can be vicious on the ice sheet. The Big House, up on stilts, rocked as each gust buffeted the structure. At around 35kn we went into Con 1 and I made the call over the radio. I could no long see the Green House from the Big House. Travel was restricted to emergency or well-coordinated necessary activity with no solo travel permitted. Two people were in the Green House and went down to the SOB together to get the mechanic and bring him back. Visibility was down to just tens of feet and we ran a rope line along the flags between the Big House and Green House. Even in those high winds it was not hard to follow the flag line, but if something were to happen, if someone were to be blown over and injured or become disoriented, the consequences would be disastrous. So we are cautious and careful.

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The storm was brief, however and winds died back down to 35kn pretty quickly. Overall the station fared well. A few large empty propane cylinders that are stored on the deck were blown over and there was significant drift growth around station. The buildings are far from perfectly sealed and we found several small drifts inside where ice and snow had been blown through a tiny crack. Walks around the berms revealed completely buried pallets in places and a few lighter items that had blown over, but not too much damage. We are prepared for potentially bigger storms through the winter.

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Wind speeds off the chart!

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Filed under Arctic, Greenland, Summit Station, Winter

Aurora Borealis

It’s a chilly evening in the heart of the ice sheet with temps hovering around -40F. We are outside, however, to witness a fantastic display of auroras! Tripods frost up, breath freezes on gaiters and hats, plastic becomes brittle, and above us the sky is alive.

I’ve written about auroras in a few previous posts here and here so I won’t go into too much detail, but a brief summary is that auroras are caused by energized particles from our sun striking gas molecules in the atmosphere (much like neon displays). The colors are due to which molecules are excited – green is caused by oxygen around 60 miles up while nitrogen causes the red-purple auroras. Solar storms and flares release waves of charged particles which can be predicted and tracked. To see the aurora forecasts and where they might be visible check out NOAA’s Space Weather page here: www.swpc.noaa.gov. NASA also has a fantastic page on Aurorae with photographs of aurorae on other planets!

Auroras dancing over the Big House

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The green line coming out of the far building in the last image is the CAPABL LiDAR I discussed in my previous post. The red light is the 50m tower.

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Filed under Arctic, Greenland, Summit Station, Winter

Lidar

It was lightly snowing last night, ice crystals falling from high, thin clouds as I walked from the Big House to the Green House. Looking towards the MSF there was just enough ice in the air to illuminate the ICECAPS LiDAR – a laser measuring cloud matter, phase, and crystal orientation. ICECAPS is a relatively large, long-term project researching cloud characteristics and their impact on climate. This knowledge is crucial in developing climate models as well as understanding our changing climate. More information can be found here: www.esrl.noaa.gov/arctic/observatories/summit.

Most of the time the laser is invisible, however with just the right conditions enough light can be reflected back to show the brilliant green beam. If you look carefully you can also see the vertical laser, however this is weaker and thus less visible. Beautiful science!

*If you are familiar with LiDARs you may have seen this spelled LIDAR, lidar, LiDAR, or LADAR – according to NOAA’s Digital Coast Blog all spellings are correct though LiDAR is gaining in popularity. 

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The ICECAPS LiDAR here at Summit

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The LiDAR at NOAA’s ARO facility at the South Pole Station

 

An example of the LiDAR data:

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Halos

Auroras may grace the polar skies at night, but the day sometimes brings phenomenal halos and sundogs. It’s hard to describe the intangible beauty of these phenomena – vibrant spots of rainbow on either side of the sun, glowing pillars of light from the sun, a brilliant stream of light encircling the sky parallel to the horizon…a good display is simply awe-inspiring.

In general atmospheric optical phenomenon (sundogs, halos, rainbows) are not uncommon. Frequent halos and sundogs can be seen around the world when ice crystals in the atmosphere reflect and refract light. Infrequent halos are more often seen in polar regions or at high elevations with colder temperatures and more ice in the atmosphere. A common occurrence with halos is “Diamond Dust” which is essentially a ground level ice cloud filling the air with glittering ice crystals.

All photos below were taken by me, click on any of the images to open the full photo with caption.


The different crystal shapes generate different optics, however ice crystals form in hexagonal symmetry, thus while the crystal might be long or short (columnar or plate-like) the internal angles are always the same. Here at Summit the ICECAPS project, housed primarily in the MSF, is researching these crystals and cloud formations to better understand the complex processes involved in these systems.

The following website is a brilliant source of information regarding atmospheric optics and identifying features: www.atoptics.co.uk. An impressive full list of optical phenomenon can be found here: https://wikipedia.org/Atmospheric_optical_phenomena. For more Summit specific photos and information check out the Polar Field Services blog, Field Notes.

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Photograph of a good halo display – 22° halo, upper tangent arc, 46° halo, and parhelic circle at Summit Station, Greenland

 

Below are some of my favorite photos of optics that I have witnessed in the Arctic and Antarctic. If only I’d had my wide angle lens in past seasons! Click on images to bring up caption and full picture.

 

According to atoptics.co.uk, 120° parhelia are infrequent, but not super rare. They are often faint and short lived however, I have only ever seen them twice. Below is a panorama at Summit showing bright 120° parhelia.

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Bright sundogs, 22° halo, and definite rare 120° parhelia! (Summit)

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Looking opposite the previous photo – the 120° parhelia can be seen along the parhelic circle (Summit)

Moon halos are not uncommon either, but require a nearly full moon and darkness as well as halo forming conditions.

 

Other interesting optical phenomena include the green flash and fogbows. The green flash lasted a few hours at the South Pole Station in 2013 (check out my post from that sunset with more green flash photos here). This photo was taken through a telescope. It’s a bit blurry due to heat waves and light distortion near the horizon, the same process which causes the green flash to be visible. Fog and fogbows are a frequent occurrence at Summit, Greenland.

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 Happy belated equinox and sunrise at Pole!

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Summer’s End

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The summer season is coming to a close and Summit Station is as busy as ever wrapping up projects and preparing for winter.

The last Herc for the year is scheduled for Aug. 17th. We’ll be left with 5 souls on station and a lot to do before the storms hit. Autumn comes fast on the ice sheet with high winds, monster drifts, and reduced visibility. As winter approaches daylight dwindles and temperatures drop as well, though most of our preparations are for the storms.

To winterize station we move the handful of summer buildings (carp shop, summer berthing, storage units, short term science space etc) away from the main station. We park equipment out in the flat white and put all implements and drags on small berms raised above grade. All cargo on station is consolidated onto pallets or crates and placed on one long berm above grade as well. With nearly a meter of accumulation each year and an infinite amount of drifting possible things get buried. It’s just one of the difficulties of life here. So we mark edges and corners with colorful flags atop long pieces of bamboo. A lot of effort is put into marking, mapping, photographing, and documenting where things are put.

We are in the midst of turnover here – as the station manager this means I am in the office long hours reviewing SOPs and where documents are stored, as well as emergency plans, schedules, and tasking to be done before winter comes. The rest of my crew has been here since June and are mostly settled into their roles. I held this position last year so most of it is review, but there are some changes here and there and it’s good to go over everything before we’re on our own. The next flights won’t be until mid-October when a Twin Otter will fly from Iceland to Summit to change out part of the crew.

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Summit Deployment

Welcome Back! After a few months off to enjoy the world of trees, mountains, swimming in lakes, and not wearing 40lbs of extreme cold weather gear the time has come to deploy again. I’m on my way back to Summit Station in Greenland. I’ll be returning as the Station Manager, the same position I held last year. This time however, I’ll be running the station through the cold, dark, arctic winter from August to  February.

In the short summer season from April-August Summit Station is a busy and exciting hub of activity. Construction projects are completed, cargo is moved with the Air National Guard, it’s home to lots of people (up to around 35), the GrIT traverse comes and goes, and multiple groups conduct their research. The sun is up 24/7 and temperatures range from -20F to 30F. Current weather graphs for Summit can be found here.

The summer is brief however, and the Hercs are needed elsewhere to support science with the US Antarctic Program (USAP) on the other end of the world. In mid-late August Summit Station shuts down for the winter (see my post here from last year: https://antarcticarctic.wordpress.com/2015/08/23/summers-end/). From August to April a skeleton crew of just 5 maintains the station and several year-round science projects. There are no LC-130 Hercs or flight periods (https://antarcticarctic.wordpress.com/2015/06/29/flight-period-4/) to deliver fresh food or new faces, just a few Twin Otter flights in October and February for crew change-outs.

At 72°North, Summit is not at the Pole, but it is above the Arctic Circle and thus has very long days in the summer and very long nights in the winter. This year the sun has been up since May 5th, but on August 6th it will set at 11:59pm to rise again just 22 minutes later at 1:21am. Gradually the “night” will lengthen until November 14th when it will become dark 24 hours a day 7 days a week. For the next few months we’ll have beautiful sunsets.

Check this link out for August sunrise/sunset times at Summit: http://www.timeanddate.com/sun/greenland/summit-camp?month=08&year=2016

It’s not as intense as winter at the South Pole, but temperatures have fallen as low as -89F and the Aurora Borealis is stunning. Check out this post on Polar Field Services Blog Field Notes about the winter at Summit in 2009: polarfield.com/blog/greenlands-summit-camp-in-the-winter.

We’ve arrived in Schenectady, NY and from here we’ll fly up to Kangerlussuaq, Greenland via the New York Air National Guard aboard Lc-130 Hercules planes. A day or two in ‘Kanger‘ and then it will be onward to Summit. It will be a busy next few weeks as we close up the station and prepare for winter.

For photos of the hercs and Kanger check out my deployment post from last year: https://antarcticarctic.wordpress.com/2015/06/22/welcome-to-summit/

 

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Ice to Ice

Phase II has come to an end. It was a great season and an especially interesting experience with both summer and winter operations. The new crew arrived right on schedule on October 8th via two Twin Otters from Akureyri, Iceland. The following week was a whirlwind of turnover with the new crew: training them on equipment and procedures, reviewing protocols and paperwork, getting them accustomed to the 10,550ft elevation and -30F temperatures and helping them get settled in with all the various idiosyncrasies that make up Summit Station.

On October 16th we officially handed over the reins. Two Twin Otters were scheduled to land just after noon, but the day had dawned with 20-25 knot winds and a fair bit of blowing snow in the air. Visibility was below their minimums with a worsening forecast. Still, the weather in Akureyri, Iceland and in East Greenland was clear and beautiful and they were going to try. As the day progressed we continued to submit hourly weather reports – the Phase III manager doing the observations. I stood by to answer any questions and assist with preparations for the flight. They had off-decked that morning on time, so while we were mentally prepared for them to cancel we also had to be ready to go. As their ETA drew closer the visibility stayed between 300-400 meters. The SOB was barely visible from the Big House.
The first Twin Otter called on the Air to Ground radio when they were about 15 minutes out asking for a current weather observation and confirming that they would attempt a landing. They could see the skiway markers, it was a localized storm, only a couple hundred meters high, and the wind was coming straight down the skiway. The mechanics pulled the loader and fuel tanks out to the taxiway, turning all their lights on to increase visibility, and the science techs readied their snowmobiles to transport freshies to the Big House and pax bags to the plane. We held our breaths and strained to see the plane in the whiteout as they reported over the radio that they had landed safely…”Norlandair 4 is on deck…but, we’re having a hard time seeing the flags, would it be possible to get a snowmobile escort to the fuel pits?” We escorted them in, began fueling, and unloaded the fresh food for Phase III. The pilots were unfazed and friendly. The second plane landed a few moments later without issue.

The first plane fueling with blue sky above

The first plane fueling with blue sky above

Norlandair!

Norlandair!

When we deployed in June 2015 we flew commercially to Scotia, NY where we boarded Air National Guard LC-130 Hercules planes and flew north to Kangerlussuaq, Greenland via Goose Bay, Canada. After a few days in Kanger we continued onwards up to Summit still on the Hercs. Redeploying now in October the LC-130s have flown South leaving Greenland for a period of maintenance before beginning the main summer season in Antarctica. Travelling to and from Summit then is done via Twin Otter – flying East with a quick stop in Constable Pynt on the rugged and isolated coast to refuel and Southward to Akureyri, Iceland.

I’ve never been East of Summit in Greenland and at first it’s the same flat white. The storm is indeed localized, not 15 minutes away the clouds clear and the sastrugi glitters in the sunlight as we cruise above.

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Fair weather just away from Summit

But then darkness appears on the horizon: mountains. Undulations form on the surface and a slope becomes apparent. I can see the ice flowing together and pulling apart, forming a more defined glacier – crevasses gape, indicating an increase in veloIMG_2677city. There’s no scale to show how huge they are. A nunatak appears, the tip of a mountain peaking above the ice. Then more – the ice lowering gradually, revealing mountains. Soon the ice is flowing between rock. Sheer granite walls rise above massive, epic, classic glaciers. Jagged peaks reach to the sky, dribbling rocks down their flanks to the ice below. Perhaps it is simply because I’ve seen only the flat white since May, but it is stunning and I can’t contain my excitement as I move from window to window. The sun is starting to set and the light is beautiful. It’s an inhospitable land: impossible to traverse. Perhaps some lichen or moss exists here, maybe the occasional bird, but there can’t be much else. Precipitous cliffs press against crevasse riddled ice as far as the eye can see. Further on, liquid water appears and the ends of the glaciers crumble into the dark reaches of the fjord. Icebergs! The sun sinks lower, behind the mountains, bathing the landscape in gold and pastel pinks and blues and we begin our abrupt descent to Constable Pynt. Not much more than a landing strip scraped clear of snow and some fuel tanks, it’s a quick stop and then we’re off over the far North Atlantic, heading south now to Iceland.

Inside the Twin Otter - the pilots up front, then the ferry fuel tank (extra fuel for the long flight) and us in the back.

Inside the Twin Otter – the pilots up front, then the ferry fuel tank (extra fuel for the long flight) and us in the back.

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Crevasses

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Constable Pynt, East Greenland

Refueling in Constable Pynt

Refueling in Constable Pynt

Arctic foxes (one white one brown) at Constable Pynt

Arctic foxes (one white one brown) at Constable Pynt

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It’s dark when we land in Akureyri. The town lights gleam and the air is laden with the smell of fall; the sweetness of decaying leaves, the hint of fresh grass and life, the salt from the sea. It’s windy and we couldn’t be happier. The next morning we fly on to Reykjavik and after a long layover, back to the U.S.

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The cathedral in Reykjavik, Iceland Oct 17

It was a record fast turnaround for me this year. Less than 48 hours to unpack and repack, take a bath, enjoy some crisp fruits and veggies, then back to the airport. Greenland to Antarctica in less than a week!
This year I’ll be working as an equipment operator on a small traverse shuttling materials from Byrd camp to WAIS Divide. There are no plans for a camp in the near future at Byrd, so much like last season (Pig DiggersWAS Recovery) it will be a skeleton crew working to return material back to McMurdo where it can be used for other projects. WAIS Divide is a fairly significant camp as far as deep field camps go – a staff of 15 will support a number of science groups operating out of there. Byrd however, will have a crew of just 4; their primary task being to excavate the cargo stored out there and either return it to WAIS Divide via our traverse or fly it back to McMurdo via LC-130 Herc. As far as traverses go ours will be pretty minimal with just two of us driving Tucker Sno-cats over the 100-mile stretch between the two field camps. In the field, far from the main stations, we will have no internet access though we will be carrying satellite phones and a portable HF radio.

Byrd has a long and varied history – from a year-round station to a summer only field camp. The Antarctic Sun did a nice piece on the history of Byrd history: Antarcticsun.usap.gov

I also reviewed some of it’s history back in 2012-13 when I was working as the equipment operator out there for the summer: antarcticarctic.wordpress.com/byrd-surface-camp-2012-13

So thanks for following along this summer! And stay tuned for the next grand adventure…The West Antarctic Support Traverse 2015-16!

Kiwi graffitti

Kiwi graffiti in Christchurch, New Zealand Oct 22

Welcome to Antarctica!

Welcome to Antarctica! Getting off the C-17 in McMurdo, Antarctica on Oct 23

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Storms and Aurora

The Big House at sunrise (HDR)

The Big House at sunrise (HDR)

We awoke yesterday to the wind howling. The Green House was filled with a deep Summit_Sunrise_HDRresonating sound as the wind vibrated wires on the roof. I peaked out my window. Seeing only flying snow in the pre-dawn light I pulled up the weather page: 35 knots. I pulled on my windproof layers, complete with goggles and stepped outside. The Big House was completely lost in the blowing snow…this is why we put up flag lines. I followed the flags to the Big House and found our mechanic inside sipping coffee. Gradually the others trickled in. As we ate breakfast and commenced the morning meeting the wind rose to nearly 40 knots, swaying the Big House on it’s stilts. Con 1: No travel unless absolutely necessary and check in via radio upon departure and arrival when moving between buildings…

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Halfway to the Big House with 35kt winds and blowing snow filling the air. Behind me the Green House was already gone.

We hunkered down, working on indoor projects and getting ready for turnover with the next crew who are due to arrive later this week. The winds stayed strong most of the day, tapering off at sunset. Darkness fell quickly. Inside the Green House after dinner we all gathered to watch a movie when one of the Science Techs went out to prepare for their nightly weather balloon. “Umm…You guys might want to pause that…there are some pretty good auroras…” After a quick look outside, I quickly threw back on all my layers and grabbed my camera and tripod. The sky was filled with one of the brightest, most active aurora I’ve ever seen. Curtains of bright green light tinged with red danced across stars, swirling and spreading.

I turned off the outside light on the Big House, however in the 2-8 second exposures the other lights on station lit the building up in a surreal light – it was not photoshopped into the picture 🙂

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All bundled in the -35F temps

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