Extreme Cold Weather Skiing

I have never been a big skier, having never lived in a place where it snows.  I have skied downhill a handful of times, and, before coming to the South Pole, I had only cross-county skied maybe a dozen times.  Nevertheless, knowing that people had skied all the way across Antarctica, I thought that skiing should be a fun outdoor activity at the South Pole.  Before leaving home I inquired with some veteran Polies and I was told that the South Pole station had plenty of skiing equipment, but the gliding would be poor, and it would not be possible to ski in the winter, as the temperatures would be so cold that the skis would nearly freeze solid with the ice.  Prepared with this grim outlook, my expectations have far been exceeded.  Since arriving at the Pole last November, I have skied almost every day: in the summer, in the winter, with temperatures down to -70 C (-94 F), and I have been having a great time, so I decided to write this blog to let future generations of Polies know that it is indeed possible and enjoyable to ski year round at the Pole, and also as a way to record the clothing and equipment that I used, my experiences about what worked and what did not work, so that I might use this blog as a future reference in case I decided to buy some of the equipment for my personal use, or for the benefit of anyone else who might be considering doing some skiing in extreme cold environments. 

Steele took this picture of me on July 1, outside of the Martin A. Pomerantz Observatory (MAPO), about ½ mile from the station.  The temperature was -63 C (-82 F), and  it was blowing a 16-knot (18 mph) wind. 

The glide: is there actually any glide here at the South Pole?

The short answer is that yes, there is some gliding, but very, very little.  To quantify the gliding I took some data point earlier in the season, at the end of March, with temperatures around – 60 C (-76 F).  I counted the number of steps that it took me to ski the 400 ft (122 mt) distance between two sets of flags along the skiway.  I did this several times in three different conditions: 1. Forcing myself not to glide; 2. using my regular Nordic ski pace; and 3. trying to glide as much as possible using the skating technique.  With no gliding it took me an average of 146 steps to cover the distance, meaning that my step was 2.6 ft (80 cm) long.  This is about the same as when I walk.  When I used my regular Nordic ski pace it took me an average of 92 steps to cover the same distance, which corresponds to a step length of 4.3 ft (132 cm).  Therefore, the gliding per step was 132 cm – 80 cm = 52 cm.  Using the skating technique and trying to glide as much as I could, it took me an average of 66 steps to cover the distance, which corresponds to a step size of 6.1 ft (185 cm).  In this case the gliding was 185 cm – 80 cm = 105 cm.  I am not sure how this compares to warmer conditions, but I suspect the gliding here at the Pole is inferior.    Another way to compare the skiing conditions here at the Pole to other locations is by comparing the speeds obtained during races.  In the McMurdo marathon on the Ross Ice Shelf here in Antarctica, on Jan 16, and with a temperature close to freezing, the winner in the ski category completed the 26.2-mile course at an average speed of 10.5 mph, while here at the Pole, on Dec 25, and with a temperature of -12 F (-24 C) the fastest skier on the much shorter 2.2-mile course of the Race Around the World skied at an average speed of 5.4 mph, and he was an experienced ski racer from the Northeast, who had even competed in the Marcialonga in the Italian Dolomites.  So, the speed here at the Pole is about half of what it is at temperatures closer to freezing.  Therefore, the gliding must not be great, but we can ski and have a good time nevertheless.  I have been skiing at a speed of 3 ~ 4 mph, closer to 4 in the summer and closer to 3 in the winter, which is kind of like a fast walk.  I have not tried to wax the skis.  I have talked to numerous adventurers last summers who skied to the Pole, and none of them was waxing their skis.  I guess the wax loses its gliding properties when it gets too cold.  The gliding is probably affected not only by the temperature, but also by the quality of the ice.  There is no snow here at the Pole, as the temperature is too cold for snow flakes to form.  Instead, precipitation comes in the form of ice crystals, which are only about 0.01 mm in size, much much smaller than snow flakes, and invisible when they are in the air.  The ice crystals remain on the ground as a powder.  They only aggregate together to form solid ice under their own pressure several feet under the surface.  Also, there is no melting and refreezing here at the Pole, so the surface is a constant dry powder all year round, with a thin crust on the top.  The ice crystals make a screeching sound under the pressure of the skis that can be heard a long ways away.  The friction between ice crystals is in my opinion where the energy of the forward motion of skiing is absorbed. 

The clothing

I ski an average of 5.5 miles each day, which takes me a couple of hours, so warm clothes are necessary.  I have found that the equipment provided by the US Antarctic Program is excellent and perfectly adequate for this activity, so I would like to give its description here.

I start with an under layer of cotton socks and longjohns.  The top, made by Kenyon,  is 100% polyester, and is commercially available; the bottom is 100% polypropylene, it is made by Peckham Vocational Industries and does not appear to be commercially available.

Then I put on heavy wool socks, or more precisely, 95% Worsted Wool and 5% Nylon.  Ours are made by Wigwam Mills.

Then comes what we call the Carhartt.  Carhartt is actually the name of the manufacturer.  This is a fantastic piece of equipment, one of my favorites of the entire wardrobe provided by the program.   These are insulated work coveralls with multiple pockets suitable to hang tools.  They are designed for outdoor work, and they are very sturdy, although not indestructible.  They even have a hook on the back, which I used in the summer to attach a rope to and haul a sledge.  I did this several times when I was skiing with Dr. Weatherwax to different locations on the ice carrying equipment to calibrate fields of cosmic radiowave antennas.  I use one of the two pockets on the front bib to hold my UHF radio and the other to hold my music player.  These coveralls are made of a 100% cotton exterior shell, a 100% nylon internal lining and a 100% Polyester insulating interlining.  They are listed on the Carhartt website as style R02, and list for $110.  So, staying warm in extreme cold weather does not necessarily require extreme $$$.  In general, cotton is not considered to be a good material in cold weather because it absorbs water and stays wet a long time, but there is no water here at the pole.  When we are outside the ice never melts, even when it sticks to our clothes, and when we walk back into the station the air is so dry that the ice seems to turn into vapor without going through the liquid phase.

We have several options for ski boots.  My favorites for the winter are made by Karhu, model Convert.  They top my list because they are the warmest.  They look like sturdy walking boots, with good insulation, and have three pins in the Vibram sole to fit the bindings.  Although these are the warmest boots we have on station I still use our Grabber foot warmers and toe warmers.  These are small packs containing a mixture of iron, water, activated carbon, and salts.  When exposed to air, the chemicals in the packs react with the air to provide heat.  They last several hours.  I am not sure how effective they actually are at our temperatures.  While they definitely provide plenty of warmth at room temperature, it looks like either the reaction slows down when temperatures get colder, or the heat generated just isn’t enough to compensate the heat lost to the environment.  Nevertheless I still use them, as they provide at least some extra insulation.

Then comes the balaclava.  I have used a couple of them through the season.  The one I have now, from Outdoor Research, is made of Windstopper fleece, and is very good.  It has lasted the whole winter, through an average of 3 hours of use every day, and through multiple washes, and still looks like new.

After the balaclava, I put on my wool hat from Nepal, and then my Northern Outfitters 100% polyester fleece top.

The third and final top layer is the very famous red parka.  This is by far the most amazing and valuable piece of clothing that we are issued.  I have never, ever, felt cold wearing it, even at -100F (-73 C), and even with the strongest winds that we experience here at the South Pole, provided of course that I do not stand still.  My feet are actually getting cold before I can feel any cold through the red parka.  In the very rare occasions when the wind chill has dropped below -140 F (-96 C), I could just start to feel the wind through.  The red parka, originally designed specifically for the US Antarctic Program, is now also a commercial product.  It is called the Expedition Parka and it is made by Canada Goose.  It has an 85% polyester/15% cotton shell, a 100% nylon lining, and a 625-fill white duck down.  It has coyote fur around the hood.  When the parka is zipped all the way up the hood cannot be lowered, which means that it will not come off even in the strongest winds.    The hood protrudes several inches forward from the face in what we call the snorkel, so as to create a chamber of warm air around the face.  In addition, the edge of the hood has a metal frame which stays rigid even in strong side winds.  If the wind ever makes it into the hood, all I have to do is to close down the opening of the hood by bending the metal frame.  This way I lose a little bit of visibility, but I can fend off the wind.  This parka also has a multitude of internal and external pockets which I use to carry small tools, emergency flashlight, fresh batteries, pencil and paper.

After the parka come the three layers of gloves.  The first is just a pair of thin wool liner gloves – the blue glove visible on my left hand in the picture.  The second is a pair of leather mittens.   The lining is 65% polyester, 35% rayon, and the insulation is made of 3M Thinsulate material.  I use hand warmers in the mittens.  They work just as the foot warmers and toe warmers that I described earlier.  Hand warmers are very effective at keeping the hands warm.  I am not exactly sure why they seem to work so much better than the foot warmers, but I suspect that the hands remain fairly warm, so that the hand warmers do not have a chance to freeze.

Finally the bear paws, and I am ready to hit the ice.  The bear paws are gauntlet mittens made by the Illinois Glove Company.  They have a 100% wool shell with leather sewed to the inside of the palm and pile fur on the outside, and an insulating detachable insert.  I found them necessary when temperatures drop below -50F (-45C).

The ski equipment

The US Antarctic Program provides us with a good selection of ski equipment.  Every item comes in a variety of sizes.  I have tried most of the equipment available to find what works best for me.

The first combination available is skating skis and boots.  The skis are made by Fisher, model BC Country Crown.  The bindings are snap-in Fischer Autoflex 105 Profil SNS.  The boots are Fischer Combi 5000.  I found this to be the best combination for the summer.  I ski mostly Nordic style, but occasionally, on a good surface, I like to skate.  These skis and boots allow both styles.  The only problem with this set is the extreme cold, and I am talking about temperatures at or below -50 C (-68 F).  Around these temperatures feet get cold after less than one hour, the rubber in the bindings becomes rigid so that it becomes impossible to snap the boots into the bindings, and the boots become sort of brittle.  I broke the metal rod in the boot, where it attaches to the binding, with no apparent stress.  This is why, at the beginning of April I started experimenting with different skis.

This is the second pair of skis I used.  They are telemark skis, with metal edges, made by Karhu, model Lookout.  The boots are Karhu Convert, and the bindings are made by Rottefella.  The great thing about this set is the boots.  They are well insulated and much warmer than the boots in the previous set.  They also fit very well.  I have tried different sizes and none of them ever produced a blister or any discomfort.  I found the best fit in a boot two sizes larger than my shoe size, which allows room for the heavy socks, foot warmers and toe warmers.  I have been able to ski for up to 3 hours at temperatures down to -90 F (-68 C) before my feet started getting cold.  However, the skis are significantly slower, probably because of the additional friction produced by the larger surface area.  It took me about 30% more time to cover the same distance using these skis as compared to the Fischer BC Country Crown.  These skis, weighting 8 lbs with the bindings, are also much heavier than the Fisher skis, which weight just 4.5 lbs including the bindings.  Unfortunately, most of the Karhu boots that we have on station have cracks, either in the Vibram sole or in the top leather, or in both.  I believe the cracks are due to the cold.  While cracks in the leather are mostly an aesthetic flaw, cracks in the sole are a big problem.  My first boots had a small crack in the sole, which eventually propagated and resulted in the sole breaking and the boot becoming useless.  I took a second pair of boots and made sure they did not have cracks in the sole to begin with, and I have now skied more than three hundred miles in them with no sign of damage.   To prevent causing damage to the Vibram sole I do not skate and I try to move slowly when on rough terrain, but I suspect that a potential cause for the damage to the boots is the fact that we currently store them in an unheated building, so I am looking for a storage place inside the station to better care for them.

I found the best winter combination to be the lightweight, low-friction, Fischer skating skis with the heavy-duty Karhu Convert boots.  This however requires a different type of binding, of which there are only two on station: the Norwegian-made Rottefella Super Telemark three-point bindings.  These bindings have worked very well at any temperature down to -94 F (-70 C), as they are purely mechanical.  Now I can get the speed and the warmth at the same time.  I don’t think I will be too hot in these boots even in the middle of summer, so I vote this as the best kit for recreational skiing at the South Pole.

The ski trails

Here is a map of my ski trails.  All distances were measured with a GPS.

Before I close I want to pay a tribute to Steele, our very competent machinist, who braved the -82 F (-63 C)temperature and 16-knot winds on July 1 to take photos of me outside.  When not at the Pole, Steele lives in Tasmania, an island off the coast of Australia.  This is his second winter at the Pole, and he may come back next year for a third.  I first met him at Fire School in Denver back in September of last year.  He has made several parts and modifications for my various projects, is a true gentleman, and is a great pleasure to share stories with.  He is also currently building next year’s Pole Marker, which will be unveiled at the Geographic South Pole during the Pole Marker Ceremony on Jan 1, 2012.



Mid-winter

Several people have been asking me about skiing here at the South Pole, so I would like to first let everyone know that I am working on a new blog on Extreme Cold Weather Skiing, which I hope to publish within the next couple of weeks.  Today's blog, however, is on our mid-winter celebration, which we observed here at the South Pole last Saturday, June 18, three days ahead of the actual winter solstice.  This is the darkest of winter for us, with the sun sitting at a constant 23.5 degrees below the horizon, but it is cause for celebration because the sun is now slowly starting its trip back up towards us, even though it will be at least 6 weeks before we can even discern any faint glow at the horizon.  In good South Pole tradition, we celebrated with a sumptuous banquet and with a group photo on the ice.

Summer and winter solstices can easily go unnoticed to people living at medium latitudes, but they are a big deal here in Antarctica.  All the stations that remain open for the winter exchange greetings, typically accompanied by a photo of the winterover group.  Here is the greeting that we sent out.  We took this photo on June 13 under an almost full moon and using a long exposure, which makes the station behind us visible.  I am the fifth from the right, standing.

We shed our work clothes for the party and try to dress up a little.  Some of us have even brought suits and ties for the occasion.  To my right is Jens, one of the two Ice Cube Laboratory scientist, who has been looking all winter long for a single extra-terrestrial neutrino.  To my left are Bill, our electrician, and Kevin, our plumber.  We try to socialize in a more formal way than we usually do, with cocktails and appetizers.

From the cocktail table I particularly enjoyed the Blue Cheese Walnut Tarragon Dip, the Roasted Red Pepper Goat Cheese Pine Nut Dip, and the Crostini, but we also had shrimp and beef pate'.

We set up a very nicely decorated long table, we played some background music, displayed a fireplace on our large LCD monitor, and enjoyed some wine, too, including some from New Zealand and some even from Italy.  Before we started the meal the station manager read a letter that President Obama sent us.  In the letter the President praised our work in furthering our understanding of global warming and closed by saying "As you mark Midwinter's Day in Antarctica, I commend you on your commitment to discovery and innovation.  I encourage you to continue to use your talent and dedication to make the world better for us all, and I thank you for a job well done."

Our midwinter dinner consisted of a Salad fresh from our greenhouse, tossed with walnuts and mmarinated dry cherries, and a main course made of Glazed Duck Breast topped with a blackberry tarragon garnish (Top), Lobster and King Crab sauteed in garlic butter topped with a champagne sauce and served in a pastry shell (Right), Broccoli, Cauliflower, and Artichoke hearts sauteed in olive oil (Bottom), and Polenta Cakes baked with sundried tomatoes, capers, and Rosemary (Left) ... delicious.

It wouldn't have happened without our superbe kitchen staff: John, Bryan, Will (the chef), Jeremy, and Ashley, left to right.  Will and I have several things in common: his last job was in a French restaurant in Denver, Co, and I speak French, and, like me, he worked in the semiconductor industry, as chef at the Sematech cafeteria in Austin, Tx, which I visited several times, so it is likely that I ate some of the food he prepared even before I came here to the South Pole.  We also shared a room, with many others, for 13 days, in McMurdo, waiting for our flight to the Pole back in October - occasionally he saves me a bowl of oat meal if I sleep in and am late for breakfast!  Bryan works dinner.  He always makes sure I get plenty of vegetables, excep on Fridays, when he knows that I turn from vegetarian to carnivore and I like my steak rear.  Jeremy works lunch and makes great tofu dishes and indian food.  He lived in Japan for some time and speaks Japanese.  John was the baker in the summer, and made me panettone for Christmas, but during the winter he is responsible for managing our food supplies.  Ashley has the biggest smile on station and must be the happiest person I have ever met in my life.

I took this photo from the deck of the station, less than 1 hour before we started dinner.  It was two days after the full moon.  On the horizon the Ice Cube Laboratory (left), and the South Pole Telescope (right) are visible in the moonlight.  They are part of my daily ski loop.  The distance to the Ice Cube Laboratory is 0.67 miles (1.1 km).

I went out on June 21, the very midwinter day, and took this photo of me at the very South Pole (temperature -85 F, or -65 C).

Aurora Australis

We are only a few days away from the winter solstice (that will occur on June 21 here in the Southern hemisphere).  This is also the darkest of the polar night, yet the sky is all but dark.  We have been blessed this year with spectacular auroras.  Some are brighter, some more colorful, and some have more structure than others, but a day does not go by without auroras showing off in our sky.  I spend an average of 3 hours outside every day, and I would be hard pressed to remember a day when I did not see auroras.  Auroras are produced by charged particles (electrons and protons) emitted by the sun.  When these particles approach our planet, they follow the field lines of our magnetic field, and therefore move towards the polar regions, where the magnetic field lines concentrate.  Before they can reach the magnetic poles, though, at a height of about 300 km from the surface of the earth, they excite oxygen molecules, which then glow just like a fluorescent light does.  Because the particles coming from the sun move at supersonic speed, so do the auroras.  They seem to constantly dance in the sky, 300 km above us.  Some of them last 10 or 15 minutes; others last as long as one hour.  This has been a very good year for observing auroras, as the sun is approaching a maximum in its emission of particles: a maximum that occurs with a periodicity of 11 years.  The South Pole, located approximately 1,000 km away from one of the two magnetic poles of the earth, is one of the best locations on the planet to observe auroras, and that is why a lot of the scientific research that we do here has to do with observing auroras and correlating the observations with other celestial phenomena.
It takes good photographic equipment, a tripod, a lot of patience, and tolerance to the cold to take good pictures of auroras.  Lacking a good camera and patience, I thank Christy and Jens for letting me use some of their photos in this blog.  All the photos shown here are raw images.  Typical exposure times are about 10 seconds.

This is what most auroras look like here at the Pole: spanning a large portion of the sky, glowing green.  Notice the stars in the sky and the Atmospheric Research Observatory at the bottom of the frame.  This aurora happened on June 6.  Photo by Christy.

This aurora, on May 25, shows some interesting structure, twisting away at the far right, and with a hint of red color.  In the foreground are the pole marker on the right and the sign commemorating the arrival of Amundsen and Scott 99 years ago.  Photo by Christy.

I call this a lenticular aurora, covering a large portion of the sky in a round shape.  This aurora occurred only a few days ago, on June 9, and was part of a series of auroras that came on display almost continuously for a period of 12 hours following a massive ejection of particles from the sun called a coronal mass ejection (CME).  We were alerted to this event from observations of the sun made by NASA.  Typically, it takes two days for the particles emitted in a CME to reach the earth and manifest themselves as auroras, so we had time to get ready.  Photo by Christy.

This is a beautiful, bright, and colorful aurora that occurred on May 3.  On the left is the Amundsen-Scott South Pole Station.  Photo by Jens.

I was skiing to the Ice Cube Laboratory under a nice aurora, on May 2, when I met Jens, who was walking to the same building, but had stopped to take a photo of the aurora.  I like his photo because it gives a realistic representation of how a typical aurora brightens the surroundings.  In the background are, from left to right, the 10-meter South Pole Telescope, and MAPO, a building that houses two additional microwave telescopes.

Auroras happen all the time, in the summer and in the winter.  It is just that during the summer we cannot see them because the light from the sun overwhelms them.  A full moon, though, is not sufficient to blind some of the brightest auroras, as shown here on May 19.  Photo by Christy.

As I said, auroras move very rapidly.  In this sequence taken by Christy an Aurora is seen starting at the horizon, then move overhead.  All the photos are taken under the same exposure settings.  The time stamp below each photo gives an idea of the speed at which the aurora is moving.  Also notice how much brighter it gets as the aurora moves overhead.  The building on the right is NOAA's Atmospheric Research Observatory.

This is what an aurora looks like to the eyes of a research camera.  It happens to be one of the experiments that I am responsible for.  This image is taken by a high resolution, black and white, all-sky camera, that takes 180 degrees images of the sky through several color filters tuned to the particular frequencies of the light emitted by the auroras.  Because of the filters, this camera is mostly insensitive to other lights, such as the light from the moon, which appears as a yellow spot on top of the image.  In reality the moon is much much brighter than the aurora, but the trick with the filters allows the aurora to be clearly visible.  These images are publicly available on the website http://www.southpole-aurora.org/ where you can see the evolution of auroras at the South Pole hour by hour.  Another interesting website is http://www.usap.gov/videoclipsandmaps/spwebcam.cfm where, in the austral winter, you can see time lapse images of auroras shown as movies.  Those photos were taken a few years ago by Robert Schwartz, who is wintering here with us again this year.

Finally, a quick note on the weather.  Despite global warming, we had the coldest May on record here at the South Pole, with an average temperature of -62.6 C (-80.7 F).  Luckily it was not a windy month, so my outdoor activities were not impacted.  On May 27 the thermometer dipped for the first time below the -100 F limit, reaching a minimum of -103.4 F (-75.2 C), as seen in this screenshot from the weather page of our intranet.  The photos on our weather page changes every 15 seconds and serve us a reminder of the world that awaits us back when our time here at the Pole will come to an end only five months from now.

The South Pole Kitchen

One reason I would like to be a millionaire some day is so that I could afford a house with a large, professional kitchen, equipped with all kinds of appliances and utensils, all within easy reach.  Until that day I may have to keep coming to the South Pole, where I have at my disposal a million-dollar kitchen every week-end that I feel like cooking.  Not only is the kitchen available to us non-chefs when the cooks take their day off from Saturday evening until Monday morning, but we also have 48 other friends willing to taste our culinary specialties or experiments, and ... we also benefit from the precious advice of our friends the cooks and the chef.

So I have been testing my favorite recipes over the past several weeks, first in small batches, then in larger and larger batches, making fettuccine, gnocchi, breads, and apple tartts. 

All the utensils, appliances, pots and pans are hanging from the ceiling or stowed under the wide stainless steel counters.  The knives, the most important tool in a kitchen, are always sharp and put away in their wood block.  The bulk ingredients, such as flour, rice, beans, are stored in easily accessible large bins.  At the end of the kitchen are two walk-in refrigerators and one walk-in freezer.   You wouldn’t think that we’d need a freezer here at the South Pole.  In fact most of our frozen food is kept on an outside deck, currently at -60C (-76 F), but it is nice sometimes to have a warmer freezer that you do not have to wear extreme cold weather gear to get in.  The kitchen is also equipped with a state-of-the-art polyphonic stereo system that we can plug our computers, iPods, or MP3 players in.

We even have an Italian pasta machine, directly from Italy, just like the one I have at home.  Here I am making some egg fettuccine on March 27.  Although we have fresh eggs (6,000 of them, kept fresh throughout the winter by a thin layer of oil patiently applied by a score of volunteers at the beginning of the season), I used eggs from a carton, to save the fresh eggs for breakfast.  Those eggs from the carton worked very well.  I also used a mixer, seen in the previous photo at the near end of the counter, instead of kneading the dough by hand.  This is a great help when dealing with 3 lbs of dough.  I dried the pasta and kept it in the refrigerator for serving it the following Sunday, Apr 3.

The day before, on March 26, I prepared green fettuccine by adding spinach to the dough.  They were also dried and refrigerated for serving the following week-end.   Because the air here at the South Pole Station is so dry (relative humidity about 3%), there is no need for a drying rack like I use at home.  Instead, I just lay the sheets of pasta on the kneading table for 20 minutes, and they are ready for cutting.  Once cut, the fettuccine dry completely within an hour or two without sticking.  This makes things a lot easier.

Last Sunday, April 10, I saw that nobody was using the kitchen, so I turned on some Italian opera sung by Pavarotti and jumped in to make some pasta again.  Here I am cooking a sauce made with diced tomatoes from a can, frozen brown mushrooms, fresh basil from our greenhouse, garlic and olive oil.  The mushrooms come straight from our outside deck at -60 C and take a long time to defrost, so I have learnt to start the sauce well ahead of time.  The range is electric, as we do not allow open flames in the station for reasons of fire safety.

One of the most convenient features in the kitchen is an electric kettle for boiling the pasta.  It is fed water by a faucet right above it, seen on the far left in the photo.  Even 2 or 3 gallons of water will come to a boil in about 5 minutes, and when the pasta is ready to drain, all we have to do is to tilt the kettle directly into a strainer, whose effluent is directly piped to a sink in the floor.  How convenient!  The only caveat is that cooking the pasta at our 10,500 ft (3,200 mt) of physiological altitude takes about three times longer than at sea level.

Here is Joselyn ready to enjoy a bowl of pasta with freshly baked 100% whole wheat bread (I was told that it would be difficult to make bread at the South Pole because of the elevation, but I found that it is not true).  Joselyn is one of my oldest acquaintances here at the South Pole, having met her for the first time at fire school in Denver back in September.  During the summer she was our greenhouse caretaker; in winter she is our waste specialist.  In real life she is a Park Ranger for the National Park Service, most recently at Big Bend National Park in Texas, where she leads Ranger walks and talks, and where she also did field study for her Master in Biology.  She loves classical music.

  

Here is Dale, serving Mexican food on March 26.  I also met him for the first time for fire school in Denver back in September.  He is one of our two meteorologists.  He writes the South Pole weather forecast every morning for our internal website.  His dream job, if he weren't a meteorologist, is to be a sous-chef.  Well, here at the South Pole he can have both.  This weekend he will be serving an Italian dinner to the entire station.

 

Before I close this blog I wanted to give you an idea of what things look like outside.  This photo was taken 13 days after sunset, on Apr 5, right at the end of civil twilight, with the sun 6 degrees below the horizon.  There is still plenty of light to see the buildings and still some orange color in the sky.  The building to the very far left is the station, seen a half mile away from the 10-mt telescope. 

In this photo taken on Apr 12, there is still some orange color in the sky, and the features on the snow are still clearly visible, although it is getting darker.  On this date we could see about 20 stars.  On April 13, it was dark enough that I was able to see my first aurora, although in the twilight it appeared grey as opposed to green and red, as they will appear when it gets really dark.  On April 15 the moon will rise and will circle around us continuously for two weeks before setting on April 29, so we expect the sky to brighten up again.

Latest weather report and forecast as of April 15: a storm coming from the Transantarctic mountains has been hitting us for the past 24 hours.  It has been blowing a 20-knot wind, and the forecast is for it to continue at least 4 or 5 days, with wind gusts exceeding 30 knots.  The temperature is -56C (-69 F), but could rise up to -45 C (-49 F).  Visibility has been less than 100 ft, and massive snow drifts are forming all over.  This storm may put an end to my South Pole running ambitions.  We'll see what is left of my running paths after the storm abates.  Meanwhile, I have been taking advantage of the time indoor to study to become a Ham Radio Operator.

Polar Twilights

We often hear that at the pole there are six months of day and six months of night, but I can now attest that this is far from the truth.  We have loooong twilights.
Before we can really call it night we get to experience and enjoy civil twilight, then nautical twilight, and finally astronomical twilight. 
Civil twilight starts at sunset and ends when the sun is 6 degrees below the horizon.  At medium latitudes it lasts about a half hour.  Here at the pole it lasts 13 days, until April 5.  During civil twilight there is still plenty of light to move around outside.  The brightest planets and stars will appear by the end of civil twilight.  It has now been 10 days since sunset, and I have still been able to enjoy running and skiing outside without any impairment, except for the wind. 
Nautical twilight is the period when the sun is 6 to 12 degrees below the horizon.  At the end of nautical twilight the horizon is still visible, and most of the stars are visible, too.  It is during this period that we turn on our cameras to observe and record the auroras.  This period at the pole lasts 17 days, until April 22.
The last one, astronomical twilight, is defined by the sun being between 12 and 18 degrees below the horizon.  The horizon is no longer visible.  It does not get any darker after the end of astronomical twilight, so that is when the night really starts.  Astronomical twilight will last 20 days, until May 12.  At that point there will only be 6 weeks left to the winter solstice, so the polar night should really only last about 3 months.
I look forward to observing the slow evolution of lights, from twilight to the night sky, with the appearance of the stars and of the auroras.  I look forward to the next moon rise, and to the lunar eclipse, which we will experience around mid-June.  Meanwhile, I am enjoying civil twilight.  On March 30 I took my camera with me on a 6.7-mile ski tour to document what the South Pole looks like at this very special time.

View towards the sun on March 30: 7 days after sunset.  The sun is about 3 degrees below the horizon.

View of the station on March 30.  There is still plenty of light to see the buildings and the features on the snow.  On this day the wind was very light, less than 5 knots, and the smoke out of our power plant created a slender and compact plume slowly drifting away.

This is a view of our beautiful 10-mt telescope against the sky opposite the sun.  While the sky was pinkish in the direction of the sun, it was of an intense blue in this direction.  Note the crust of ice on the sides of the building, produced by ice fog and wind in the preceding days.

I skied all the way out to one of the three wind turbines that were installed last summer and are being tested to support remote science experiments.  This one is located 1.5 miles away from the station, in the direction opposite to the skiway.  The path to the wind turbine is well marked with flags.

On the way back from the wind turbine I met my friend Robert, who was walking back to the station from the telescope.  He took this photo of me.  With a wind of less than 5 knots (6 mph) the -63 C (-81 F) temperature felt very comfortable.

Loving it here at the South Pole!

Robert is an astronomer, or, I should rather say, a polar astronomer.  He has already spent 6 winters here at the South Pole operating a variety of different microwave telescopes.  When not on the ice, he lives in the lovely town of Garmisch, in the Bavarian Alps (the site of one of the most famous downhill courses in the world cup ski circuit), or teaches nature classes on board cruise ships around the world.  He is also teaching an 11-hour college-level astronomy class here at the South Pole, every Monday after dinner.

Sunset

We were so lucky this year to be able to see a long and beautiful sunset at the South Pole!  The official sunset occurred at 2:54 PM on March 23 local time.  If the earth did not have an atmosphere, sunset would have occurred about a day earlier, but because of the refraction of light when it hits the atmosphere, we enjoyed one extra day of sunlight, and we will get another extra day of sunlight at sunrise in about six months.  In the days preceding the sunset a thick ice fog shrouded the area, visibility dropped to less than 1/4 mile, and our hopes of seeing the sunset appeared doomed, but then, miraculously, the fog dissolved and cleared the air for a view of a spectacular sunset, my first one since I left New Zealand on Oct 19, and likely my longest ever, lasting a good couple of days.
We set up a 12" telescope in the galley and took turns at the eyepiece to try and see the very elusive green flash.  The green flash is produced by the refraction of light against the atmosphere.  Just like the color of the sun changes to red at sunset, in a phenomenon of reverse mirage, a green band of light can become visible at the top of the setting sun, when the atmospheric conditions are right.  It occurs at all latitudes.  Sailors on the ocean are the most likely to see one.  It is called a flash because it lasts a fraction of a second at mid-latitudes.  Here at the pole, with a sunset lasting days, under the right conditions, the flash lasts several seconds, and it comes and goes for hours at a time.  The right conditions at the South Pole this year occurred in the evening of March 22, and then again in the morning on March 23.  I was lucky to be in the galley for a late dinner around 9 PM on March 22, after spending the afternoon skiing, right at the time when the sun decided to display the green.  I could not see it with my naked eye, but could clearly see it through the telescope.

Christy was able to record the green flash with her camera in the morning of March 23.

In the days preceding the sunset, as the sun revolves lower and lower on the horizon, the shadows get longer and longer, and the plateau changes its appearance hour by hour.  On March 17, it looked like an ocean, with just the top of the sastrugi lightening up like the crest of the waves on rough seas.  As a reference, the tower in the picture is 100 ft (30 mt) tall.

This is the last photo of the sun before a dense ice fog came down and reduced the visibility to less than 1/4 mile threatening to deprive us of the only sunset we were entitled to in more than one year.  I took this photo on March 19 at the end of the skiway, 2.5 miles from the station, where I went on skis.

A steady wind during the following two days blew the ice fog against anything that would stand up against it on the plateau.  This is what the station looked like when the fog started to disappear on March 22.  It looks very wintry, even though, astronomically, this is still summer down here.

There has been a lot of activity in the station around sunset, as we are trying to catch the last few days of daylight and twilight to complete outdoor work, before darkness sets in and makes things much more difficult.  Six of us have been going out to the wasteyard all week long to sort a large amount of construction materials left behind at the end of the summer.  Everything needs to be sorted into what can be re-used, what is recyclable (and we have 22 categories of recycling materials) and what is not recyclable.  In the end everything needs to be taken off the continent, in full respect of the Antarctic Treaty.  We have been working two hours every day in -60 C (-76 F) temperatures before the cold has been forcing us back inside for hot drinks.  We should be able to finish today.  In this photo, taken on March 22, the sun appears as a shade of orange behind the dissolving fog.

As the sun reappeared out of the fog in the evening of March 22, I put on my skis,turned on my MP3 player, and to the tune of Bach's Brandenburg Concert I went back to the end of the skiway for a shot at the sun disappearing beneath the sastrugi.  The orange circle in this photo is sunlight diffused by the remaining fog.  The actual sun is the very brightest last sliver of light right up against the snow.  I will not be able to listen to the Brandenburg concert again without thinking back to this fabulous ski trip.

On March 23, to the tune of Spyro Gyra, a CD that had accompanied me all the way to the AGO site when the sun was the brightest, I went on my last run of the summer to wave good-bye to the sun for the next six months, but at -61 C (-78 F), and with a windchill of -84 C (-120 F), it was a short one: only 2 miles.  A little later, at 1 PM, and just two hours before the official sunset, I went on the roof of the station to take the last photo of the sunset.  Here again, the actual sun is the thin line of bright light closest to the horizon.  The cloud of smoke seen in this photo is from our nearby power plant.

As tradition obliges, we celebrated the sunset with a sumptuous dinner on March 19, the Saturday before sunset.  The menu included Crostini and Baked Shrimp Wrapped in Bacon and Cream Cheese as appetizers, Duck Breast with Mixed Green, Lobster Tail and Beef Tenderloin with a Jack Daniels Demi-Glaze as the entree, three different desserts, and Australian wines.  We set up a long table for the 49 of us, we played some old Billie Holiday songs, and watched the fireplace on large LCD screens while the sun shone its last rays into the room (photo courtesy of Susan).

My contribution to the sunset dinner was the ironing of all the table cloths.  Susan took this photo as I was hard at work in the laundry room.

Now that the sun is down, the science work will take on a new pace.  We have to shut down the solar observations and, in a couple of weeks, at the end of the period of civil twilight, which will occur when the sun reaches 6 degrees below the horizon, we will start turning on the instruments that look at the night sky.  For me this includes two all-sky cameras that record auroras and two high resolution interferometers that measure wind speeds in the mesosphere (that is 100 km above the earth) by Doppler shift of oxygen molecule emissions.  The pyranometer in this photo on the roof of the Atmospheric Research Observatory has been measuring the bightness of the sky all summer long.  The arm on the right of the instrument roates to shadow the sun and remove its contribution from the measurement.  Seen in this picture is also the full moon, which occurred at the same time as the sun was setting.  Yesterday, March 24, we saw Venus for the first time, and we expect the sky to start turning on its stars one at a time over the next few weeks.  The moon and the stars will be the only lights to guide us for the next six months, as we will continue to venture outside for work and for recreation.