McMurdo Thanksgiving

Thanksgiving is one of the most important holidays in the US, so it is an important day on the McMurdo calendar as well. In civilisation, it’s usually celebrated with big family gatherings on the last Thursday of November, making for a four-day weekend typically filled with football and Christmas shopping. At McMurdo there is so much that needs to be done in such limiting circumstances that a six-day, 60-hour work week is standard; taking three whole days out of the peak season would be unconscionably profligate, so instead they celebrate Thanksgiving on the following Saturday and luxuriate in a rare two-day weekend.

Growing up hundreds of miles from extended family, and being a fan of neither football nor shopping, the primacy of the holiday had mostly passed me by; in the years I was an adult in the States, I usually spent it with other ‘Thanksgiving orphans’ doing something atypical. Perhaps the most important Thanksgiving of those years was the one I spent in New York on the promotional gig for Princess and the Frog, because that’s where this adventure started. I was working that day, but they catered a turkey dinner for us at the venue, and I ate my roast and sweet potato off a paper plate backstage while reading The Worst Journey in the World for the first time. Exactly ten Thanksgivings later I was in Antarctica, where it all took place.

The early expeditions knew the importance of good food. Obviously as a source of energy, getting sufficient calories was a prime concern, but when one is starved of most of the pleasures of life, food takes on a great emotional significance as well as biological. The cook on the Discovery Expedition was so bad he was sent home when the relief ships came. Both Scott and Shackleton learned from this experience – Shackleton brought a wide variety of ‘luxury’ foods on the Nimrod Expedition, and Scott made sure that the cook on the Terra Nova could turn his hand to making ordinary meals delicious and extraordinary foodstuffs palatable.

The biggest event in the Heroic Age culinary calendar was the Midwinter Feast, which took on the significance of Christmas, for not dissimilar reasons of brightening the darkness and cold. At Cape Evans, Midwinter 1911 began with a multi-course meal replete with sweets and alcohol, followed by toasts and the presentation of an ersatz Christmas tree bedecked with amusing little presents for everyone, and finally the table was collapsed and cleared away for a slideshow and a dance. Cherry-Garrard declared “It was a magnificent bust.”

American Thanksgiving falls during the Antarctic summer, so unlike the Midwinter feasts of yore, a lot of the activities are outdoors, and involve the New Zealanders from around the corner at Scott Base as well. There is a manhauling race (which the Kiwis always win) and a foot race called The Turkey Trot, which runs a loop around Cape Armitage and back through The Gap. Costumes are not compulsory but have come to be expected, so I went to take photos.

A runner arrives

The rainbow assembles – the figure centre-right with the splayed legs is wearing a turkey costume.

And they’re off!

Some of the first successful returnees

Being an open day, there was an uptick in tourism from the New Zealand side as well:

McMurdo’s mighty kitchen crew, with extra volunteer labour, had been working to prepare the feast all week. There were a number of scheduled seatings throughout the day, to regulate flow and make sure everyone had a table. I met with my coordinator’s other ducklings outside the Galley at 4.30 for the 5.00 seating, and when we were allowed in we got to see how the rather utilitarian Galley had been done up as a nice buffet, with tablecloths and everything.

I was particularly amused by this offering, given that Capt. Scott’s great food craving from the southern journey on the Discovery Expedition was a great big bowl of Devonshire cream:

It was actually cream, none of that Whipped Topping stuff.

We found our seats and tucked in. Most of my tablemates were British and it was their first experience with some American Thanksgiving standards – the pecan pie in particular got an enthusiastic vote of confidence.

You can’t see it in this photo, but the group behind us, to the right of the frame, had had some orange trays made (vs the Galley’s usual blue) that read ‘Make Antarctica Great Again.’ As far as anyone could tell, they were not being ironic. In a community dedicated to science, where even the dishwashers are likely to have a university degree, there is a certain amount of tension under the current US administration. Government support makes McMurdo possible, but the anti-science, anti-conservation tilt of The Powers That Be render it precarious, and the MAGA crowd at Thanksgiving were the subject of much anxious whispering over the next few days.

Exuberant after-dinner larks are as much a feature of Antarctica now as they were a hundred years ago, only with the advantage of electricity they are now quite a lot louder. I am not one for crowds or noise, and had had quite an intense week, so my plan was to make for the dormitories before the impromptu nightclubs opened, but I did stop in to see the one my friends had been setting up. They were down to get some specific footage for a documentary series, but the weather had not been on their side, so to fill their days they had put a great deal of time and effort into converting the gym into a dance club. Regrettably I don’t have any photos of it, but they did a really outstanding job, and the verdict the next day was that Club 77° was the best venue in town.

For my own part, I was happy to hit the hay.

View from my dormitory window

If you’re curious about what goes into feeding Antarcticans, PBS’ Nova did a great little feature on it here:

And yes, the pizza really is that good.

Sea Ice: Crack Safety

Water ice is a curious material: though apparently a solid, it can nevertheless flow, bend, and wrinkle. The mile-thick Antarctic ice cap is very gradually flowing out to the edges of the continent, through the mountains in glaciers, and when those glaciers leave their channels they spread out like hot fudge (only much slower).

Most of the time, though, what ice does is crack. In a glacier this makes a crevasse; on sea ice, it’s a short trip into some very deep, very cold water. When you’re travelling across the sea ice, it’s the cracks you need to worry about, and once you start looking for them they are everywhere. This would be enough to put off a cautious traveller but most of them are relatively harmless: the requisite sea ice training helps you determine just how risky your movements are.

First, you have to learn about how sea ice forms. You will not be surprised to learn that this happens when liquid water meets cold air.

The nice flat young sea ice is never allowed to let be, though – forces in the water underneath and air above, or even changes in temperature, put strain on it, and to release the tension it cracks.

Like a broken bone, or a fault line in rock, once ice has broken it is more likely to break again at the same place, so being aware of cracks will show you where you ought to be extra careful. Simple cracks are usually one-time releases of stress, and once refrozen rarely pose a risk, but you need to be wary of working cracks because they have shown they are unstable and their condition might change without notice.

Because they are much larger, working cracks tend to be more visible, sometimes even when the sea ice has a layer of snow on it. Pressure ridges show up very well and are a useful indicator that the ice has been moving around. Here is a very small pressure ridge just off McMurdo Station:

The snow blowing across the sea ice has been caught and drifted by the protrusions of the pressure ridge. When you have an recessed working crack, instead of a pressured one, the crack gathers the snow and shows up that way.

When you come across one of these, you have to find out what is going on under there before you know it’s safe to cross, so the following procedure is taken:

Here is the crack you saw earlier, with its snow-covered secrets revealed.

Each vehicle has different parameters for what a ‘safe’ crack is. Most tracked vehicles – snowmobiles, Hagglunds, etc – can safely cross a crack whose width is 1/3 the length of their track. So, if your snowmobile’s track is 90cm long, you can cross a 30cm crack even if it’s open water. (I would balk at doing it, myself, but it is theoretically safe.) You measure the maximum width of the crack to see if it’s within your vehicle’s safe crossing threshold. If it isn’t, it might still be safe to cross after all, but you will need to do some more measurements to find out.

Measuring sea ice thickness is great because you get to use a) a power auger and b) my favourite device in the Antarctic toolkit.

You drill either side of the original crack to make sure the ice – which is weakest here, remember – is within the specified necessary thickness to support your vehicle. You don’t have to memorise this number because your teacher has given you a laminated card with a table of all the vehicles and their requisite ice thicknesses. Your job is not to lose the card.

Once you’ve ascertained that the ice either side of the widest crack is safe, you find a point within the safe crack width for your vehicle and measure the ice there. So, using the example from before, if your snowmobile with 90cm tracks comes up to a 45cm crack, you cannot cross, so you find a point 30cm (the safe width) from your side of the crack and measure the thickness of the ice there.

If the ice at the safe width is thick enough for your vehicle, then that becomes the effective width of the crack, and you can cross over. The actual width is the objective total width of the crack, whereas the effective width is the width that matters to you practically.

The reason you have to drill again at (3) instead of just subtracting the change in surface elevation from the measurement you took at (2) is because of the irregularity of the underside of the ice. You don’t know if there will be a big lump of nice solid ice there, or if it will be a surprisingly thin patch, so you have to check. For this same reason, you can’t measure a crack in one place and cross in another, because conditions along the crack can change completely in just a few metres.

Part of the job of the Sea Ice Master* at McMurdo is establishing ‘roads’ for vehicles to take to regular destinations (e.g. Cape Evans, the seal camp at Turtle Rock, Penguin Ranch, etc). Usually the ice is thick enough that these roads can go more or less directly there, but this year the ice formed so late, and in some cases was so choppy, that the roads snaked and dog-legged all over the place to find safe crossings. On top of that, the early summer had been exceptionally warm, and there was a great deal of nervousness around just how long the sea ice would be traversible at all. Luckily there was a cold spell just before I arrived, which bought enough time for me to travel to Cape Evans. In my last few days at McMurdo the sea ice did finally get closed to all traffic and the flags marking the roads were brought in, so it was a close run thing.

*not the actual job title, but should be