Forms Of Snow

Photos © 2005 Seth White

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A look at Scott Base, on a trip back to Erebus to shore things up at our installations at the Truncated Cones site. Things for sale at the station store here include Scott Base underwear (mens and womens), nipple warmers, and little patches that say "Ice Wings" with a nude man and woman embracing passionately...or at least with as much passion as a sewn patch can convey. Good stuff. No word if their shipment of Peter Jackson's Signature Fuzzy Handcuffs has arrived or not (they're Hobbitastic!). The McMurdo store has some good stuff in it, such as some neat glassware Zippo lighters, and replica South Pole markers, but in my opinion the Scott Base store is slightly better overall. The items that tip the balance are the shirts. T-shirts are the default souvenir for a lot of people, and the McMurdo designs are generally pretty lame. I swear the USAP employs one part-time graphic designer who gets 30 minutes a year to come up with 8 designs for next year's shirts. Honestly, it's like the same person has his/her hand in every single t-shirt (and hat) design in the store. And friends, this person is running out of ideas. There are or have been shirts for every natural or man feature on or around Ross Island, and every historical event that took place on Antarctica. I've seen Ob Hill shirts, Castle Rock shirts, Cape Royds shirts, shirts for Shackleton's "James Caird" voyage, shirts for Ivan the Terrabus, and so on ad nauseum. Next year we'll have a new line of shirts for the Sea Ice Transition Area, the Ham Radio Shack, and the great 2002-03 pteropod invasion at the seawater intake. Currently, my favorite one is a black shirt which says "The Heroic Age of Antarctic Exploration" on the front and lists various explorers on the back, including one "Ronald Amundsen". Great. Our friend the Graphic Designer managed to misspell the name of probably the greatest polar explorer in history on a shirt dedicated to such people. Also noteworthy on this shirt: the explorers are listed with both first and last names, i.e. Ernest Shackleton, Douglas Mawson, etc, but poor Dumont D'Urville only gets his last name (i.e. Dumont is NOT his first name). I was tempted to take my camera in the store and snap a shot for a "spot the mistakes" feature. But I have prattled on long enough about this - it's lame and embarrassing, but alas quite a trivial matter. No word other than "trivial" really seems to fit when talking about the design of T-shirts for sale in Ant-freaking-arctica. But before we move on...
...I need to post this file: a promo for a Raytheon community involvement program. The marketing people are overselling the power of mathematics just a bit here...I'm afraid that the Pythagorean Theorem or Euler's Identity cannot magically teleport polar bears to Antarctica. And as we speak, Juan Alvarez, budding Marine Scientist, is driven by this cruel delusion to pull an all-nighter cramming for his algebra final. Inevitably the poor guy will realize that there are no polar bears in the Antarctic and, hopes dashed, will abandon his scientific aspirations and slowly descend into madness, ultimately whittling away his days in the purgatory of lame t-shirt design and corporate promotions. By the way, on a positive note we are getting two C-17 flights this week. I don't think these were orignally part of the season's transport plan but we have fallen a bit behind on cargo, so the Air Force is doing these two flights...which will bring in many times more cargo than the same number of LC-130 flights. And on the first flight are 8 pallets of mail, which has been languishing in Christchurch but will now get here in time for Christmas. Excellent.
OK, sarcasm aside - back to the point of this page: the real beauty of Antarctica. The pressure ridges in the sea ice near Scott Base have been building up over the past few years, and these "rollers" have really increased in size as the sea ice folds into ripples. This area next to Scott Base is kind of a little cranny where the land, sea ice, and ice shelf meet. As the ice shelf advances and the sea ice shifts, the forces at work line up in such a way as to form these ripples.
Another incredible natural feature of Ross Island: the Erebus Ice Tongue. This is basically a fast-moving glacier that flows out into the sea to form this floating "tongue" of ice. I am not sure why the lobes form, but my guess is that it's due to the annual sea ice. With open water in the summer the ice can advance freely, but in the winter the sea ice cover holds it up and the ice flow bunches up at the land/sea transition, forming a lobe. There is no shortage of eminent glaciologists within the Crary Lab that I could ask for a definitive answer about this, but I just haven't done that yet. As an aside, since the sea ice hasn't flowed out in years (due to the gigantic icebergs blocking the outlet of McMurdo Sound), there are new pressure ridges building up around the ice tongue. The field safety guys are interested in this area so they asked if we could put numbers on the relative motions involved here. Last week we finally had the time and the equipment was available, so Thomas went out with them did it. One GPS receiver was set on the ice tongue, one was positioned on the sea ice, and the motion of both were calculated relative to a base station on the land of Ross Island. Preliminary data showed the following: the ice tongue is moving westward at about 0.4 m/day, while the sea ice moves westward at only 0.2 m/day. So both are moving westward relative to land, but the ice tongue is pressing against the sea ice.
Antarctica New Zealand's helicopter "HNO", a Bell 212 similar to the ones the USAP uses. A nice looking aircraft, especially with the Erebus crater behind it.
This page has the better pics from two trips to Mt. Erebus, and while making it I noticed that the majority of them show interesting forms of snow and ice: pressure ridges, the ice tongue, sastrugi and rime ice (both farther down the page), and these things: ice towers. Fumaroles are vents for heat and gas on the mountain, and layers of ice build up around them to form ice towers. There are caves underneath these towers, and the snow above can be very thin, ergo a good idea to keep your distance. Some of the scientists have been down in the caves studying gas emissions etc., but I have not had the pleasure yet. So, the telephoto lens had to suffice. This is one with the crater plume behind it.
I posted some ice tower pictures back in 2003 when I first visited Erebus. A lot of them. But I'm still struck by them, so here are more.


This has become one of my favorite pics from this season. Hard to believe, but this IS actually a place on earth.
OK, one more. Here is one steaming away. It was perfectly windless and sunny this day, perfect for watching the steam silently floating up from these things. Our helicopter was about an hour late picking us up, so we had time to enjoy the views after the work was done.
Walking around the mountain northward from the Cones site we found some waves of extremely hard, wind-packed snow ("sastrugi"). Almost liquid and glossy with the sun shining on it, and quite slippery in spots.
Nearby a line of ice towers was this little hole on the side of a hill, which looked like a fumarole recently opened up without enough time to grow an ice tower. Pretty, but I gave it a wide berth.
A tiny human, daring to breach the domain of the ice towers.
A variety of scientific instruments and their associated power systems at Cones. It's not a great shot for showing rime ice, but you can see it formed on the structures, in particular the guy wires and wind generator blades. This stuff is formed when supercooled water vapor carried along by winds impacts a solid surface. The solid material gives the vapor a "nucleus" surface to condense on and it freezes into rime ice. Rime always forms on the windward side of objects. And Cones is a VERY rimey site. Huge layers of the stuff can form here, and it can be a real test for the equipment.
The sea ice airfield. This year the runway was constructed on the ice channel cut by the icebreaker last year. This "first-year" ice was a lot smoother and easier for the runway crews to clean up than the nearby "multi-year" ice. As I write this (12/20/05) this airfield equipment has been completely moved over to Williams Field as the sea ice is softening up and melting. So this location is just a bare patch of ice now. The Russian icebreaker Krasin is now at the ice edge and will begin cutting this year's channel soon (if it hasn't already). Yep, we're now relying on the Russians to keep the USAP in full swing for another year. Our icebreakers Polar Sea and Polar Star are in bad shape from beating their heads against thick, multi-year ice while breaking the ice channel the past few years, and are in need of major work. The Krasin, although less powerful, actually has better icebreaking capability than these two ships. A major flaw in the design of the Polar Sea and Star is ballasting - they are not equipped to take on sea water to maintain their weight as they burn fuel, and so their downward icebreaking force decreases as they get farther into their journey (and unfortunately, the last part is where they meet the thickest ice). These ships and their crews have done some incredible work for the USAP, but the future of US icebreaking is very much up in the air. As always, the issue boils down to money. NSF doesn't have the $, and the Coast Guard doesn't have the $. And congress doesn't seem too anxious to cough up the $, so I dunno how it'll all play out. A google search will probably yield some info on the latest developments if you're interested.
On one flight back from Erebus, the pilot decided to buzz the snow school...we came in pretty low and could see people laughing and waving. So here's a pic of the group as we went by.