Grease Ice and Purple Sunrises

Dec 20, 2008

Of all the different ice types in Antarctica (yes, there are different types, including brash, nilas, fast, frazzle, grey-white, 1st year, and multi-year ice), grease ice is my favorite. You can’t tell that it’s ice, and you can’t see any crystals or whiteness to it at all, but grease ice is an extremely thin layer of ice crystals on the surface of the ocean so thin that in still water you can’t see it or tell that it exists. If you were to throw a penny off the ship, though, the ripple that formed would move outward much more slowly than water because of how the crystal sheet bends outwards, and it’s a really cool sight. (Hence the name ‘grease’ ice because it moves like oil and when it’s a bit thicker has a sheen to it like oil does.) When the ship moves through grease ice you can’t see it being cut but it looks like sailing through smooth ripples in jello. I’ve taken some pictures that show the sheen and slow-motion rippling effect of grease ice but I don’t think that images will do it any justice out of context back home. It’s a surreal sight, particularly in the calmer 2/3am light I’ve seen it in a few times as I wake up for my late-night experiments.

greaseiceripples-mClick for a much better view of the thin, clear ice layer on the water

One of the difficulties with my research on this ship is that the ‘timer’ on my equipment was broken during the transit through the Drake Passage, so instead of having chemicals measured every four hours automatically, I have to be awake every 4 hours of every day in order to process my samples. This means that I’ve been working daily from 8:30am-1:30am, and also waking up to work 3:30am-5:30am. It’s not ideal and means that sleep is a very elusive concept at the moment. Granted, quite a lot of people on this ship are sleep-deprived so I don’t mean to complain too much, but I feel like every once in a while I should remind myself that I’m in gorgeous and amazing  ANTARCTICA and I should take a few minutes to look around when I can escape from the other work I have to do.

Because of this problem though, it means I’m awake at all sorts of odd hours, and the lower-set sun is stunning. The sun never sets in austral summer in Antarctica (I’ll explain that concept in season 2 or 3!) but it does get low in the sky, dipping down near the horizon before jumping back up again in a mix of simultaneous sunrise/sunset. The lower sun casts long shadows and a purple hue in the sky at around 2am “ship time” (there are no time zones at the Pole since all of the time zones intersect there, so with 24hr daylight we just pick an arbitrary time and stick with it so we know when meals are), and the night crew and I seem to be the only ones awake to see this amazing glow.

2amsunriseice2-mSimultaneous sunrise/sunset in the land without a setting sun

sailingovergreaseice2-mMore grease ice. See the sheen it creates?

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Posted on 2008, in 2008 (12/20) Grease Ice and Purple Sunsets, Season 1: Life on an Antarctic Icebreaker. Bookmark the permalink. Leave a comment.

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