12/17/19 – 12/20/19 WAIS Divide

As I am writing this, I am currently sitting on an LC-130 en route back to McMurdo from WAIS Divide. We boarded about an hour and a half ago, and I just woke up from a nap and decided this would be a good time to write. First I guess I’ll give a little background about where I’ve been the last 3 days, before I get to what I’ve been doing. The West Antarctic Ice Shelf Divide (WAIS Divide) is a Deep Field Camp located at 79.46 S, 112.08 W, about 1021 miles from McMurdo. The trip is approximately 3 ½ hours by LC-130. AWS has many weather stations near WAIS – the station just outside base, Byrd, Kathy, and Bear Island (Peninsula*). Looking back on the last couple days, I wish I could have spent more time there. There was no cell phone service, no internet, and almost nothing to do but play cribbage. The community is very small, around 57 people. Everyone pitches in their part in the form of house mouse duties, such as doing dishes, cleaning, sweeping floors, and even shoveling snow to melt for water. That’s right, all of the drinking water at WAIS is shoveled melted glacier ice from the “Snow Mine”, and it tastes very good. The food is also pretty good. The two cooks, Jesse and Cat, cook for everyone on camp. It’s definitely the same frozen base ingredients as McMurdo food, but better prepared and spiced.

The setting

The environment in WAIS is a complete change from McMurdo. The first and most obvious change was the landscape. WAIS is literally in the middle of nowhere. Besides random softball size snow-chunks scattered thru ought the surface, the area is fairly featureless in every direction. WAIS is located on top of more than a mile of glacier, an ice shelf which extends between the Transantarctic Mountains and the Atlantic Ocean. This altitude (6000ft) brings me to the second biggest change, the weather. WAIS Divide is much cooler and windier than McMurdo. The air is also much drier, with a relative humidity around 5% and much lower dew points. The weather was pretty variable for the short time I was there. I saw everything from sunny and clear skies, to heavy blowing snow, to freezing fog. The temperature also varied quite a bit, from 15 to -10 degrees Fahrenheit.

There aren’t nearly as many amenities in WAIS as there are in McMurdo. The camp is only active during the summer months and is taken down during the winter, so all camp structures are either temporary “rac tents” or “modules”. These structures serve for all of the primary staging areas for the functions of the camp. Rac tents are large, half-cylindrical thermally insulated tents with a wooden infrastructure. The main rac tent is The Galley. Here, breakfast, lunch and dinner were served. The camp also held daily morning meetings after breakfast around 7:30am. The galley also contained the glacier water melting system. Near the back door, on the other side of the rac tent as pictured on below, a large 500-gallon drum was nearly full of fresh drinking water. Other rac rents included the Pilots rac tent, and the Rec. These rac tents were each about 1/3 the size of the Galley. 

OLYMPUS DIGITAL CAMERA

Modules are basically stripped out double-wide ice fishing shacks on sleds. Modules serve many purposes for WAIS. There is Comms, which provides a workspace, power outlets, and VHF radios for research groups. The Wash module, where there are showers (only cold), sinks, and a single washing machine. The Medical module, where a single physician assistant on is on duty. Other structures included the bathrooms, which were very memorable unheated outdoor outhouses. 

I slept in a 7 x 5 foot mountain tent thought the trip. It was surprisingly warm. Since the sun never sets, the tent had the ability to stay warm pretty well as long as someone was inside. The tents bottom tarp, two base layer thermal pads and a thin thermal insulated air mattress separated my fleece lined REI sleeping bag from snow and ice below. When going to bed around 10pm, I’d be freezing cold by the time I get into the sleeping bag. It would warm me up to a comfortable level pretty quickly, however. Since we were technically in Denver time zone, peak sunlight occurs around 3am McMurdo time. The extra sunlight would cause my tent to heat up to 60 or 70 degrees and wake me up to unzip the -80F rated sleeping bag every night. All USAP bases and camps run on New Zealand time to avoid confusion. Otherwise one would be passing a time zone for every 80 miles of latitude or so, with all time zones converging at the South Pole.

The story

Originally, only 7 of us were manifested to fly on December 17th. It didn’t really work out the first try though. Low visibility and low cloud cover had pushed our transport time from 6:30am to 9:30pm, then 3:30pm. After more attempts, the flight was cancelled, with a new transport time rescheduled for 9:30am the next day. This is somewhat typical for flights in and out of WAIS. As I found out later in the trip, conditions in WAIS can change quickly. Weather forecasters are looking for stable weather to activate flights, especially expensive and long-distance ones like this. Fast-forward to the next morning, I woke up around 7am and quickly ran to the galley to check the flight manifest screen and to catch breakfast. On checking, the flight read as “Activated”. I was slightly surprised as we were told the night before the flight may not activate due to weather. After eating, I grabbed my things and reported to building 140 for transport. Lee, 9 others and I were then loaded into and driven in a “Delta” to Willie Field. A Delta is basically a diesel tractor with massive, wide, snow tires and a sheet metal crew cab bolted 6 feet off the ground. The inside of the Delta was lined with every kind of sticker one could imagine. Everything from NASA, to In-And-Out Burgers, the Vikings football team, to the old AWS sticker. Upon arriving at the airfield, our LC-130 was being fueled. We were told we had about a half an hour before departure. In the meantime, we hung out in the galley and chatted with the other groups flying with us. It was now time to depart. We loaded ourselves back into the Delta and were driven to the plane nearby. Once we were off, we grabbed our things, stopped for a few pictures, and boarded the airplane. It was going to be a tight fit; WAIS had just recently had a 14-day flight blackout. The plane was stuffed to the ceiling with crates of supplies. We sat along the sides of the plane in netted seats and stacked our carry-on bags into a pile in the middle of the isle. The doors closed, and minutes later we took off, beginning our flight to WAIS. The flight was smooth, and the sky was clear. Not a whole lot happened during the flight. There was only endless ice tundra to see out the windows. Most of us took a nap or read books/tablets. I worked on some previous blog posts on my laptop during the flight.

View outside LC-130 en route to WAIS

Coming into WAIS, low fog prohibited visibility and I wasn’t able to see much out the window. We touched down, and we began taxiing into base. About a minute after landing, the back hatch of the LC-130 opened up. The Air Guard loadmaster and his crew began untying crate loads which they shoved off onto the taxi-way as we were moving. We soon came to a stop and were told we could exit out the front of the plane. I stepped off and looked around. We were in front of a supply field, with two Twin Otters and a DC-3 Basler parked maybe 100 yards away. Yellow Rac Tents and some rectangular metal structures (Modules) could just barely be seen just beyond the airplanes through the fog. We were greeted by James, the camp leader, and told to meet in the galley, the main staging area of WAIS Divide. There, James reintroduced himself, then gave us an overview of how things work at WAIS. We then went around the room introducing ourselves, where we are from, and what research team we were with, to the rest of the camp.

James – brown sweatshirt standing back – camp meeting

The only AWS tower we were able to service at WAIS was the station about a quarter mile outside of camp. This tower had been failing to transmit since last winter and needed servicing. On the first “night” arriving at WAIS, after Lee and I were oriented with the camp, we walked to the tower to inspect it’s condition and height. The tower structure and angle to ground were fine, there wasn’t any visible damage to any sensors, and there was no ice grime present. The instruments on the 12ft tower were quite low to the ground however, because WAIS accumulates about 4ft of snow per year. Upon opening the enclosure, the CR3000 datalogger failed to power up. This meant that something was wrong with the power / charge controller system, which explained why the tower wasn’t transmitting. That was pretty much it for that evening – we walked back to camp and slept in our tents.

The next morning, we checked out a snowmobile with sled. We loaded it up three 12V 108AH gel-cell AGM batteries, spare parts & tools, and took off for the tower. On arriving to the tower, we began measuring the heights of each instrument, noting them in a notepad. Our first objective was to replace the batteries and check out the charge controller system. This meant digging through a few feet of snow to reach battery enclosures. Even though the snow was light and clumpy, it still took a ton of extra effort due to the high altitude of WAIS. One thing to note was the large amount of ice enclosing the battery boxs. We used aluminum ice picks to chip through it, eventually exposing the plastic enclosures. Hoisting out the two battery boxs beside the tower, we opened them up. It was immediately clear the batteries had failed. They were bubbled up and registering only 6V with a multimeter. The fact that they were physically damaged indicated some type of failure in the charge controller. Unfortunately we didn’t have a spare charge controller, but we decided to replace the batteries anyway. After hooking everything up, the system looked and felt fine. Battery voltage and current draw seemed normal. We then felt confident to fire up the datalogger. It powered up and began working immediately. In light of the charge controller seemingly working, we guessed that our wind power generator had overcharged the system, causing the charge controller to not function correctly either by overcharging, or shorting the batteries. Hopefully replacing the batteries reset the system.

Battery enclosure dig at WAIS

Our next objective was to raise the tower and the instruments accordingly. This required us to unbolt and remove all of the instruments, place a new tower section atop of the existing one, and replace the sensors to their proper heights. The instruments are secured by U-bolts with 5/8″ and 9/16″ nuts. Some instruments, such as the net radiometer, are secured on a 6ft horizontal boom arm always facing north. Others, such as the RM Young Wind anemometer & wind vane are secured with a pipe fitting clamp at the top of the tower. PRTs, thermisors, and relative humidity sensors are located at incremental levels about the tower. Some of these instruments were at heights which required one to climb the tower. After Lee and I worked to remove the lower instruments, I mostly just handed him tools as he climbed to remove the upper ones. Removing the instruments was pretty simple. Once Lee secured the 7ft tower section, we began refitting the tower with its original instruments.

This is where things started getting interesting. As we were working, an LC-130 was coming in on approach to the WAIS airstrip. Conditions were getting hazy, and we could only hear the roar of its engines. A minute or two later we heard the crunch of the aircraft landing on the surface, and the skidding of its skis across the snow. Climbing partway up the tower, I could just barely make out the silhouette of the aircraft’s tail before it disappeared back into the fog. The fog was becoming more and more dense, and we could no longer see base camp. We continued to work for a while, installing instruments and taking measurements. Over time, we realized that the temperature was rapidly dropping. Ice began to form on everything, a phenomena called Freezing Fog. The tower, our jackets, even our beards were slowly glazing over. The added relative humidity also causes cold air to feel colder than usual, much like a wet sauna feels hotter than a dry one. Eventually, everything was hooked together, and we fired up the datalogger. Out of curiosity, we checked a reading from it’s surface-level platinum resistance thermometer: -22.4C (-8.3F). Pretty cold for standing out there for 6 hours. Before leaving, I had to snap some photos of the landscape surrounding us. The sun and halo around it looked absolutely fantastic, like something out of Hoth from Star Wars. I’ll never forget the feeling of looking off into that distance and seeing nothing. Walking in that direction in those conditions would mean almost certain death. I was not afraid, but in awe at how vast nature is.

Sun in Freezing Fog – WAIS

to be continued…

2 thoughts on “12/17/19 – 12/20/19 WAIS Divide

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