Friday, December 27, 2013

A month of updates

So, I just looked at my blog and realized that it has been about a month since I last posted. Between work and the holidays and activities outside of work it's been a very busy month. Probably the biggest news in my work category is that one of my projects, SuperDARN (which I talked a little bit about in my last post), suffered some pretty serious damage after Arrival Heights had some Condition 1 weather last weekend.
Those lines that angle towards the ground aren't supposed to do that

Lines dragging on the ground. In the distance, you can see that a pipe is laying on the ground.
On Saturday and Sunday, we were in and out of Con 1 (sever) weather up at Arrival, mostly due to severely reduced visibility. The fog left everything rimed with frost (which you can still see some of on the first picture), including SuperDARN. On Saturday, when I checked on things, everything was obviously still standing. On Monday, I came back up and decided to do a walking inspection and found a big mess. Several of the anchor lines had failed, and a pipe at the end of the array had bent over to the ground, all of which combined to bring down a number of the antenna cables. My best guess is that the frost got too heavy, and a couple of the anchor lines, which were already weakened and going to be replaced in the next couple of weeks, just gave out. At this point, I've let the group know what has happened and now it is up to people who get paid a lot more than me to figure out how to deal with this sort of loss.
Other than that, work has been fairly quiet. Last week I got the chance to head to the Dry Valleys with AFTAC, one of the groups I support. Actually, until last week, I hadn't done much of anything with them except chat with the guys who were down here. That project suffered some pretty major losses of its own over the winter. The guys, William and Eric, spent most of there month and half down here flying back and forth from their sites, replacing battery banks and repairing generators. I came along for their last trip out to "help" with the last of the generator maintenance. I did actually help some, but they mostly brought me out to show me the sites at Mt. Newell and Bull Pass, and to let me explore some off station. It was pretty awesome.
Draining coolant, in preparation for replacing coolant lines
The helo dropping us off at Mt. Newell

Looking down into Wright Valley from Mt. Newell
We spent the morning at the AFTAC Mt. Newell site. Most of the morning was taken up with replacing coolant lines on the generator that keeps the building warm and battery banks charges. I did get about 45 minutes to hike around and got a good look at where we'd be heading next, just below Bull Pass in Wright Valley.
The helo dropping us off at Bull Pass
Wright Valley was completely different from Mt. Newell, and it was easy to see where the Dry Valleys get there name. The floor of Wright Valley is clear of snow and is a mix of gravel and sand leftover from when the glaciers moved through and pulverized all the large rocks that used to be here. While there were two generators to work on at the Bull Pass site, we got things done quicker, and had a fair amount of time to explore.
First Eric took me out to the Onyx River, a glacially fed stream that is the largest in Antarctica. It also flows "backwards" in that it flows away from the sea and towards Lake Vanda which is about 2 miles further down the valley. Since the water is pretty much untouched, we filled our water bottles straight from the river. It was very good water. After that, Eric and I hiked up into Bull Pass. Much of the rock in the area is a black shale, I think. Anyways, it all looks like the kind of rock that should break off in sharp pieces, but due to centuries of wind and sand, the rocks have become ventifacts, or wind-carved rocks. It was very cool and a little strange to climb around in them, since many looked like faces staring out of the mountain.
Standing on someone's head in Bull Pass
After coming back from the Dry Valleys, I spent a day in town working and then headed out for Happy Camper, an overnight snow-craft and survival class. It used to be required for pretty much everyone on station to take it, but now the only people required to take it are those heading out into the field for extended periods of time. It's a boondoggle for everyone else, and it was a blast. We spent the first couple of hours in town, talking about hypothermia and frostbite and those sorts of things. Then we piled into a Hagglund with all our gear and headed out to the ice shelf where we spent the night. After getting an intro to the WhisperLite stoves that everyone uses down here, we put together sleep kits (two mats, a -20F bag, and a fleece liner), and grabbed tents to set up.
Gear drag out to our site

Sleep kits!
The standard mountain tent that gets used out in the field.
After setting up tents, we got a quick tutorial in how to cut snow blocks and set up wind walls. Then we were basically free to do what we wanted. Some folk set up the kitchen:
Our kitchen, complete with stove-top, seats and a wind wall
A lot of us took the nice weather as an opportunity to dig out snow trenches to spend the night in.
My snow trench, all set up for the night.

Todd, coming out of his snow mansion.
The entire thing was a blast, and I slept warm all night. I got a chance to go skiing in the evening. I even planned on skiing in the morning, but I woke up to barely being able to see the tent next to my hole and decided to go back to bed for a while. This was the first camping trip in a couple of years that I haven't been the first one up and cooking, so that was a pretty nice experience all by itself.

Once I got back in to town, I found out that Arrival Heights had been in and out of Con 1  and went up to check on things. That night we had a masquerade, complete with home-made masks made earlier in the week.
My favorite photo from the evening, with Debb, Megan, and Bev. This is the only one where I am not completely cracking up.
On Monday I lead what I though was going to be the last pressure ridge tour of the season (although it now looks like I've got at least one more), and I got my friend Erin out for the first time. She was very excited to see seals.
Erin, extremely excited
Seal tail! With a tag from one of the seal groups

Snow-eating seal

A pretty cool picture of the pressure ridges
Christmas down here was wonderful. There was a station-wide Christmas party Tuesday evening, Christmas dinner, live music and dancing on Wednesday, and relaxing and hanging out with friends on Thursday. Part of the festivities on Wednesday was the Ob Hill Uphill, a half mile race to the top of Ob Hill.
The group racing to the top
Near the top

Friday, November 29, 2013

Science Post: Riometers, Photometers, Magnetometers, and SuperDARN

The broadband riometer array at Arrival Heights
So, last time I said that I'd start talking about some of the science I look after here at McMurdo. A-111 is a combined project involving, a riometer array, photometers, and a magnetometer. The riometer and photometer systems help study the process of energy transfer from the solar winds to the Earth's magnetosphere and ionosphere at high magnetic latitudes. The riometer array picks up galactic radio noise, which is assumed to be constant at any point in the celestial sphere. These radio signals are absorbed by ionized air, so fluctuations in signal intensity signal changes in the ionization level. These changes can be cause by solar UV and EUV radiation, galactic cosmic rays, solar flare protons, or aurora-associated energetic electrons. The data is process to isolate effects due to energetic particles. The photometers measure photo-emissions at two auroral wavelengths for correlation with the riometer data. Lastly, the magnetometer is used to study hydromagnetic wave phenomena in the magnetosphere. So, all of this is a long way of saying that this project studies aurora.
Checking the signal cables out to the riometer array
My responsibilities for this project include daily and monthly checks on equipment. Every day I check on the computer read-outs, to make sure that data is still being collected and transmitted off continent. Earlier this season, one of the computers failed which made for an exciting couple of weeks. However, Gil and Bob, two of the grantees on the project came down last week, bringing with them a replacement computer, and a brand new one. The new one is going to run in parallel with the other computers in the system, and if all goes well, it will completely replace the others next year when the group comes back. At the beginning of each month I also do a walking inspection of the signal cables and the riometer array up at Arrival Heights. And since I am "off station" I get to bring a buddy, or buddies, with me for safety and extra hands and eyes. We check the cables for wear, patching them with electrical tape if need be,  and check the riometer array for alignment, missing antenna arms, and damaged anchor/stabilization lines. It is a nice hike in good weather, and makes me pretty popular with people who want to get off station for a couple of hours.
The imaging riometer antenna.

One of the other projects I support is the Super Dual Auroral Radar Network, or SuperDARN for short. The McMurdo SuperDARN is part of a network of 32  radar systems looking into the polar regions of the Earth. The radars measure the position and velocity of plasma irregularities in Earth's ionosphere. The movement of these irregularities responds to energy coupled into the auroral regions from the solar wind and magnetosphere. This means that SuperDARN provides information regarding the Earth's interaction with the space environment.
In the SuperDARN antenna field
Every week I do a drive by of the antenna field, checking to see that the antennae are still standing and that the anchor lines are still attached. If we ever get big storms, I'll walk the field to do a closer inspection, which I did at the end of last month, when we had our one Condition 2 day so far this summer. Everything was still in good shape.
Melt pools, now with actual liquid
 Outside of science a lot has been happening. We celebrated Thanksgiving almost a week early, at the the food was great. We also got a two day weekend for the occasion, which is always exciting. There were a number of activities to over the weekend, including a Turkey Trot 5K out to Scott Base and back. That included an uphill almost the entire first half and 15 knot winds blowing in the wrong direction on the way out, and in sort of the right direction for the way back in. The weather has gotten really nice. We hit 35F earlier this week, which isn't unusual for this time of year, but temperatures in the 20s are more normal. With the warmer temperatures, we've also officially entered mud season. The roads are kind of a mess in places, and we have little rivers running all over the place. On my last pressure ridge trip, we saw four seals, three of them up close.
A pregnant seal right off the flag line.
One day last week, after finishing up soccer, we came outside to be treated to a pretty impressive display of fata morgana, which is a type of superior mirage.
Fata morgana across the Sound.
From what I've heard, this phenomenon cause a lot of trouble to the early explorers of Antarctica. They would come outside one day to see these huge cliffs across the way, and decide they wanted nothing to do with that. Then they'd come back a while later and the cliffs would be gone. The name itself is derived from the Latin for fairy and from Morgan le Fey, the sorceress from Arthurian legend. It's pretty cool.
And I got a package from home, which is always very exciting.




Wednesday, November 20, 2013

The View From Arrival Heights, Warm Weather, and other Miscellanea



A selfie up at Arrival Heights. On a clear day, you'd be able to see Mt. Erebus behind 2nd Crater.
 So, McMurdo  has changed a lot since I got here a month and a half ago. We are now at about 900 people, which is about as big as it’ll get. We still have more people coming in, but field camps are opening up, so a lot of the science groups will be heading out as soon as the helo’s are available.
I’m still waiting to find out if I’ll be getting a roommate. Since there are a bunch of people no longer coming down due to the shut-down and start-up, there is room in the upper-case dorm (like the one I’m in) and the administration has opened those dorms up to folks with fewer ice days (It is going from 131 days on ice, down to 127 days). The upper case dorms have bigger rooms, with a bathroom shared between 4 people, rather than a floor of people. I know a couple of people who were notified that they could move if they wanted to. They decided not to, since they are settled in to their room and they’ve actually got a great view, and the dorm they are in is empty enough that they actually have the bathroom to themselves, at least for now. So, it is possible that other people will feel the same way, and I’ll be able to procrastinate moving my stuff to one side of my room for a while longer.

I posted a couple of pictures on Facebook of my Halloween costume, but I thought I put a few up here for those that didn’t see them. I went as Tony Stark, which meant I could dress the way I normally do, and just added a home-made “arc reactor”, which consisted of recycled LEDs and computer part.
A work in progress. This is before I mounted the cover on it.
Finished product. I mounted the whole thing on the chest strap for my HR monitor, and stuck the battery in my pocket.
The weather has gotten a lot warmer in the last week. Warm in this case means that it has been in the teens and low twenties. And the wind has been low, too. All this means is that I’ve been able to stop wearing my big jacket, and have been running around in my Vakava jacket, or a sweatshirt, and maybe, maybe a hat. The warm weather has also started one of three McMurdo seasons: the slush/mud season. There have been ankle deep puddles popping up all over the place, especially around high traffic areas, which can make getting to meals a challenge. From what I hear, it will only get worse, up to some building requiring that you take your boots off before coming inside. Once the mud season ends, which is when the temperature starts to drop again and things freeze, we get dust season. Then sometime around last sunset we’ll get into cold/snow season, which will last throughout the austral winter and into winfly next spring.
Mt. Erebus from Arrival Heights. There is a little orthographic uplift happening, which is what causes the layers of clouds.
I think that I’ve said it before, but Arrival Heights, where a bunch of my projects live, has probably one of the best views of Erebus and McMurdo Sound on station. And I’ve got pictures to prove it. I keep meaning to bring my wide-angle lens up to take in the full view from the roof, but that hasn’t happened yet. I will post that when I finally get around to taking it.
Looking out towards McMurdo Sound
Along with the instruments in the Arrival Heights building, I’ve also got antennae out away from the building, and up in Second Crater (about a 1mi hike from Arrival Heights). About once a month I hike out to these, to check cables, realign antenna and just see what kind of shape things are in. Since it is technically away from station, I am supposed to bring a buddy along, for safety. So, at the beginning of the month Erin and Debb joined me to do just that.
Mt. Erebus from 2nd Crater

Erin and Debb checking out one of the anchors for the VLF antenna

Erin with the Royal Society Range in the background




Next time I’ll start talking about some of the different projects I’m working on. And I will leave you with this, the terror of McMurdo:

The Skua, a scourge upon those who carry their food outdoors.

Sunday, November 3, 2013

Pressure Ridges

The pressure ridges with Castle Rock and Mt. Erebus in the background
I was able to get out to the pressure ridges during my first two weeks in McMurdo. I liked them so much that when the Rec department started looking for volunteers to lead pressure ridge tours, I signed up right away. Alister, the guide from my first tour, also ran the training for the volunteer guides. There were 11 of us in my class, and another 10 who got trained in later. We started with about an hour in the classroom, about the pressure ridges and some of the dangers we should be in the look out for when we take groups out.
The parking meter for Americans at Scott Base
So, what are the pressure ridges? In a lot of ways they are very similar to the mountain ranges that are created when plate tectonics shift. They are formed when the ice shelf (glacial ice, in this case the McMurdo Ice Shelf) collides with the sea ice that forms along the shore. The glacial ice begins to crush the much thinner sea ice, which causes ripples and waves to form in the ice.
A crude drawing of the pressure ridges. 
Eventually these waves buckle and crack. If the waves crack on the top portion, or crest, then entire slabs of ice can rise from the surface.



Some interesting ripples on the underside of an ice slab
If the bottom portion, or trough, cracks, it forms a “melt pool”. Melt pool is a misnomer, since, at least at this point in the season, nothing is melting; it’s just sea water flowing through the crack in the ice to form a pool.
Melt pool surrounded by ridges
And another view
Many times, the Wendell seals, who live on fast ice (as opposed to the Crab Eaters and Leopard seals, who live out in the pack ice) will use the cracks as breath holes, rather than having to make their own with their teeth. Seems like a good plan to me. Once a male seal takes over one of these holes, they will defend it from other males, since who ever controls the hole, controls the females in the area. Right now the seals are in pupping season, so in another month or two we should have seal pups hanging out on the ice.