Snow Pits and Snow Angels

The project I, along with my advisor Jack and a crew from Brown U. (represented by a graduate student named Dorothy), are working on calls for snow samples to be taken on all sorts of time resolutions. Most days, we take surface snow samples every twelve hours. This gets bumped up to every four hours for a 48-hour period once a week which is less than awesome as it means someone has to grab a sample at 3am. We're actually in the middle of one of these 48-hr samples right now and I have the lovely task of grabbing that 3am sample. This post is the only thing keeping me awake for it!

Sampling from shallow snow-pits is also slatted for the project though much less frequently than the surface samples; only two pits will be dug this campaign, one in the middle and one at the end. We take snow samples every 3cm down until the pit depth (21cm). These samples will give us an idea of how nitrate, our pollutant of interest, changes with depth. The idea that as you get further down, you get further from light and thus the nitrate is less likely to participate in the sunlight-driven cycling mechanisms we observe near the surface.

Last Friday, less than 48 hours after my arrival to the camp, was the chosen day for the first of the two snow pits. While I wasn't feeling particularly stellar (the altitude was still getting to me), it was a good day to get to work on the pit as the weather was nice and Jack was still in town (he leaves us this Tuesday) to show Dorothy and I the ropes of pit digging. It's pretty simple; dig a hole a bit over 21 cm deep, flatten the sampling wall (which lies upwind of you so as to avoid contamination), and get to work. Since we're dealing with very sensitive chemistry, extra caution must be taken to avoid contamination. The solution? Plastic gloves and a plastic full body suit. Baby blue and cut from a shiny nylon material, these onesies are pretty stylish. I was so psyched about them, I asked Jack to pose in them for a picture with me.


Clearly we're both thrilled about the suits. I mean, how can you not smile if you look like a telly tubby?

Jack, Dorothy, and I each took a stab at sampling from the pit. The whole process didn't take very long (definitely under an hour) but was long enough to make some cold fingers, toes, and rears. Yes. Rears. To sample, we were seated on a ledge opposite the sampling wall as seen in this action shot of me.


Unfortunately, I didn't wear my snowpants to do this so all that separated my behind from the snow was the thin clean suit, a pair of Carharts, and a pair of long underwear. I will certainly not make that mistake next time!

While I was literally freezing my bum off, Jack was playing in the snow. Here's a picture of him trying to make Summit's first snow angel.


Unfortunately, he planted himself in a hard, packed patch of snow so the final imprint wasn't all that impressive.


In the world of snow pits, ours is definitely lame. Typically, pits are on the order of meters deep as they are most often used to look changes in snow chemistry and/or structure over longer periods of time. To quote Zoe, a researcher here drilling a 100m ice core, our snow pit is anything but a pit; rather it is more of a snow "pothole".

Jack showed us a real snow pit after we finished up work on our pothole. This hole was mostly dug for a display for the Ambassador but, true to her scientist self, the digger, Zoe, took some samples out of curiosity. This pit definitely put ours to shame. Both Dorothy and I could fit in the hole (albeit not comfortably) and when standing in it, the surface was at my chest. One of the main reasons we hopped in the pit was to get a good peek at the layers in the snow. The best way to see the layer is set up a situation in which the sun back lights one of the pit walls. To do this, Dorothy and I had to duck into the pit as Jack covered us with a piece of plywood. Once covered we were facing this gorgeous wall of blue stripes.


The picture above is of a corner in the pit. As you might suspect, the different shades of blue represent different layers of snow, but did you know that they also represent the different seasons at Summit? During the Winter months when the winds are raging, more dust is transported to Summit and is deposited in the snow giving winter layers a darker color than summer. This pattern persists all the way until snow becomes glacial ice. In fact, if I'm not mistaken, these seasonal layers, along with snow deposition rates, are how scientists determine the age of ice cores, such as those used to examine the climate over hundreds of thousands of years.

Perhaps it was the "heavenly" scene the back lit snow pit provided but after crawling out of the pit, I decided to make a snow angel myself. Learning from Jack's mistakes, I searched for a softer spot to flail around on. Here was the final product.
Ok so it's not that impressive either. It was still fun to make though and fortunately, there's plenty of snow around to try again.