Field Work

I am back in Christchurch. I left on a C-130 flight operated by the New Zealand Air Force this morning. Clearly, I have fallen behind my posts. I am going to play a little catch up with a couple posts sharing events from the past week and then a final post to close out the season. A few weeks ago I wrote a post on our field work at Tall Tower and labeled it "Part 1". A friend reminded me that I never followed up with that post and overall I have not written much about the field work from this field season. In this post I'll go through two trips in a 10 day period of the field season.

As an opener, it is fitting for me to provide a quick summary and purpose of the work in Antarctica. I am here as part of a project funded by the Office of Polar Programs of the National Science Foundation with a focus on measuring precipitation in Antarctica. This is the second of three fields seasons and this year the concentration is on the maintenance and repairs of the Antarctic Precipitation Systems (APSs). While something as simple as measuring precipitation (snowfall) seems basic it is actually very difficult to do in Antarctica. This is even more true when it is attempted to be done remotely and with the requirements to be run on batteries during the long polar night. The instrument at the focus of the measurements is a weighing bucket precipitation gauge. The gauge collects the snow and has a sensitive scale that weighs the collected snow providing a liquid water equivalent measurement. The gauge by itself can have a difficult time collecting the snow if it is unshielded and there is any level of wind. We have installed a wind shield around the precipitation gauge that is designed to slow the horizontal motion of the precipitating snow so that it is able to be collected in the bucket. In addition to this instrument configuration, we also have instruments to measure particles in the air, wind speed, temperature, measurement of the height of the snow surface, an instrument for particle size and velocity, and a webcam. All of this data is collected by a datalogger and we are able to communicate to the datalogger through an internet connection to McMurdo and then radio communications from McMurdo to the APS sites. This comms configuration allows us to monitor and analyze the observations year-round from Colorado.

Friday, November 23, 2018

This trip was our return trip to Tall Tower. Because of the great weather during our first visit, the amount of work that needed to be completed was somewhat limited. We had removed the datalogger and the instrument to measure particle size and speed and they were re-configured in the lab in McMurdo. We re-installed the two pieces of equipment and verified that things were running correctly. Some other small repairs were done to the instruments and precipitation wind shield. Lastly, at the end of a field visit, I take a series of photos, to capture the status and condition of the instruments, and a series of measurements of the height of the instruments to the surface. This final survey was completed and we were ready to fly onto the next APS site.

The next site to visit is the Lorne APS site. This site is approximately 50 miles to the southeast of McMurdo Station. Typically, the transportation to get to this site is by helicopter. However, we had sufficient time in our day that it was an easy stop on the return flight from Tall Tower. I should add that the conditions at both Tall Tower and Lorne were not as nice as they were on the initial visit to Tall Tower. The winds were around 18-20 knots and the temperature was about 16F. Those are far from horrible conditions but not the beautiful conditions that we've had so many other times during this field season. At Lorne we did similar maintenance and repairs to the site as we had done previously at Lorne and Phoenix APS sites.

One unique part of the visit to Lorne was the removal of a power system (solar panels, batteries, cases) for an instrument that had been installed at Lorne seven years ago. As I described previously, the sites on the Ross Ice Shelf generally have snow accumulation of approximately 1-2 feet per year. That means that over the past seven years the power system for this instrument has been progressively getting buried. We we were at the site a year ago and there was only about 12" above the surface. It was agreed that we would remove this power system on this field visit and return it back to McMurdo. Most all of that work was done by the two field engineers with UNAVCO and the two Twin Otter pilots. They spent about three hours digging a hole down about seven feet to remove the large power system.

Frequently, whenever it is available, we are asked by various support and logistics coordinators for us to bring people from town with us into the field. Officially the trips are referred to as "morale trips" to boost the experience and morale of workers that do not get to leave McMurdo. More frequently they are referred to as "boondogglers" as they get to experience and see a part of Antarctica that they are supporting in their work in town, but they rarely get to see directly. On this trip we had two boondogglers. They were told that they would need to be able to shovel snow. The two boondogglers started to help with the digging out of the power system at Lorne and then Scott and I each used one of them to help us with the work we were doing on the APS instruments. This day in the field will likely be one of the highlights of their season in Antarctica and fun photos are often a part of the trip.

Wednesday, November 28, 2018

When we left the Lorne APS site on the previous visit we had hoped that we had completed all of the necessary work on the APS system, but we were not entirely certain. After getting back to the lab in McMurdo it was realized that a few of the instruments were not working as expected. Fortunately, a return trip to Lorne was also needed to install a GPS receiver, which is being provided by UNAVCO. We once again traveled by Twin Otter as there was Twin Otter availability and the helicopters were still busy catching up from the late start to the season. We also took two more boondogglers with us. When we got to the APS site we were hoping that a quick fix was going to solve the problem with the  three instruments. The expected quick fix was not the problem. Within about 15 minutes we were able to identify a wiring issue and that fixed two of the instruments. The third instrument was more difficult. We ended up spending over an hour troubleshooting the instrument, which measures particle size and speed, to diagnose the problem. Such an in-depth level of analysis is best avoided when doing work in the field, especially on this day with 20 mph winds. In the end, it was determined that the instrument was not communicating with the datalogger and it was pulled to be further investigated in the lab. We would later determine that instrument could not be fixed during this field season and will be returned to Colorado.

We were able to get back to McMurdo in time for a late lunch. That also meant there was more time to get some work done during the day. Earlier in the season we had completed all of the work at the Phoenix APS site except for the re-installation of the webcam and tightening of guy cables. These are two fairly easy tasks to complete so we took a fat-tire truck, required for driving on the snow roads, and drove the 45 minutes to Phoenix Airfield, the location of the Phoenix APS. For local trips we do not have to go through the boondoggler system. I knew of a dining assistant (DA) who had the day off so she came along with us for the quick visit. The work at Phoenix APS took the expected 15 minutes and then on the return back to McMurdo we also stopped at the Willie Field APS site for some quick tests. Overall, it was a busy day of running around and seeing three of the four APS sites.

The Story of a DFIR

The last 10 days have been far busier than I anticipated. The weather for this field season, since I arrived, has been spectacular with mostly sunny to sunny days on nearly every day and warm temperatures. The result of that has been a continuous run of field work. We did two flights on the Friday before the Thanksgiving Saturday celebration. That Sunday evening we went into the field to one of the local sites for two hours, and returned that next morning for a long day at the site. On Wednesday we had a flight to Lorne APS in the morning and in the afternoon we took a quick drive to the Phoenix APS. Then on Friday we had a long afternoon with a crew of five at the Willie Field APS. The good news is that we are very close to being done with the field work. The bad news is that it has been a week since I have written a post.

The Double Fence Intercomparison Reference (DFIR) shield is the World Meteorological Organization standard for providing a shield around a precipitation gauge measuring snow. As a part of this project, we included a DFIR shield so that we could compare the measurements made with our Antarctic-focused wind shield and precipitation gauge design. The thinking is that we'd be able to develop a function that indicates the multiplier, in relation to wind speed, to be applied to our shield and gauge design to that of the DFIR.

The construction of the DFIR at the Willie Field APS site in November 2017 with the assistance of two carps.

The DFIR is a large and cumbersome shield to assemble. This is why we had no intentions of installing a DFIR at all four sites. Instead, we constructed the DFIR setup at the local Willie Field APS site so that it would be near to town to support the construction and maintenance of the DFIR. Part of the DFIR was constructed in Colorado before being shipped to Antarctica. Other parts and the assembly of the DFIR was done a year ago in McMurdo at the Carpentry shop. We also had two "carps" in the field with us for an entire day installing the DFIR. The finished DFIR has an appearance similar to that of a snow fence. The top of a DFIR "picket" was 78" above the surface and the outer shield has a diameter of 40 feet. The finished product looked great.

The finished DFIR at the Willie Field APS site in November 2017. The top of the shield is 78 inches above the surface and the diameter of the outer ring is 40 feet. 

During this past February we were seeing in the observations exactly what we had hoped to see. The plot below shows the three different precipitation gauges (we also installed one with the Antarctic double-shield at the same height as the DFIR) at the Willie Field APS site. The plot below shows the three different rates of accumulation depending on the wind shield and height configuration for the precipitation gauge.

A plot of precipitation accumulation at the Willie Field APS for early February 2018. The three different lines show the different rates of accumulation dependent on the different precipitation shield design and height above the surface.

However, as the austral spring turned to winter, something odd happened in the observations. The accumulation in the DFIR precipitation gauge (solid blue line) increased much more dramatically than the others. By mid-March, the DFIR gauge leveled off at values greater than 110 mm (liquid water equivalent), meanwhile the other two precipitation gauges were in the 60s. From afar in Colorado, this seemed really odd. The observations did not match what we were expecting. In fact, there was even some question if the instrument was failing. Adding to the drama, in mid-August the precipitation gauge, with the Antarctic double-shield at the lower height, had a similar characteristic to that of the DFIR in March.

The odd behavior of the DFIR shielded precipitation gauge (solid blue line) in March 2018.

The mystery was solved with some photos provided to us a few days before we arrived in McMurdo. It was also confirmed in our first field visit to the Willie Field APS site. We found the DFIR wind shield, installed at a height of 78 inches, to be nearly completely buried. I expected the Willie Field site to have an annual accumulation of 1-2 feet and now it was over 3 feet at the instrument tower and over six feet at the DFIR. In the end, we created our own snow drift and it resulted in a dome of snow centered around the DFIR and extending to our other instrument locations.

The buried DFIR shield and precipitation gauge at the Willie Field APS site in November 2018.

This also presented a big question as to what do we do now. Initially, there were naive thoughts that we would dig it out. The more we thought about it, and showed the photos around town, that idea quickly disappeared. In fact, the photos for the DFIR getting buried have been a big hit around town, including many senior support personnel. Thoughts were put into an operation that could remove a move a much larger quantity of snow. Along the way, we also agreed that we did not want to install the DFIR again for another year. The chances of it burying again, as well as all of the effort to install it again, were not appealing. Instead we came up with a modified experimental design for the site.

After discussions among various support work centers around town, the implementer for our project was able to put a plan together. We were going to get a bigger shovel to assist us. The plan was for a bulldozer to work during the night shift, Sunday evening after Thanksgiving, to clear the snow away from the outer ring and to push the snow away from the DFIR. The work that we had to do Sunday evening was to finish digging out the instrument cable and to provide instructions to the bulldozer operator.

The bulldozer clearing away the snow from the outer ring of the DFIR shield.

The finished work by the bulldozer removing the snow from the outer ring of the DFIR.

We returned the next morning and were greeted by an excavator to finish the work with us. The bulldozer and done a great job in clearing the snow away from the outer fence. We had to dig down at the joints for each outer section and unscrew each section and then carry each section to the truck. After doing that for all 16 outer sections, the excavator started doing the major work. The excavator progressively removed the snow that had accumulated between the outer and the inner DFIR shields. Once that was done, we had to remove the sections from the inner DFIR shield. Then the excavator had to remove the snow leading to another shield and finally the instrument. Fortunately, the excavator operator was amazing in his operation of the excavator and he was able to gently carve away at the snow with the giant bucket. It was a master piece of work. Eventually we reached the precipitation gauge at the center and removed all of the remaining hardware and the installation tower. The entire day with the excavator took six and a half hours, and that included our lunch break. It was amazing to have the assistance and support of the bulldozer and the much, much bigger shovel of the excavator. I don't know how else it would have gotten done.

Thanksgiving

Thanksgiving weekend at McMurdo Station is a pretty big deal. One of the reasons why it is such a big deal is because it is a rare two day weekend with most all other weekends a single day (Sunday). That means it gives people a chance to unwind and relax a little more. The station and operations also shut down more than a typical weekend. The focus of the two-day weekend is the Saturday, when Thanksgiving is celebrated. There are a variety of activities throughout the day, the bars are a little livelier, and some workcenters are also frequently hosting smaller parties. From Friday evening until Sunday afternoon it can be a flurry of activities, or a chance to relax and rest, which oftentimes does not happen.

The start of the Turkey Trot 5K. I am in the fourth from the left, in all black, and bib number 1143.

One of the big events for Thanksgiving is the Turkey Trot 5K race. There are actually two 5K races. The Turducken is run Friday evening for those that are working during the actual Turkey Trot. There are also some people who run both. The Turkey Trot has become a big event for those that run, and those that prefer to walk the 5K. For this year's Turkey Trot there were 150 entrants with a current station population of 895 people, or about a sixth of the station. Typically, a large number of the participants dress up in all sorts of costumes for the Turkey Trot. There are collections of costumes throughout the station that have been around for years and emerge for big events such as Halloween and the Turkey Trot. The actual race is sort of brutal. Roughly the first half of the race is run uphill on a crushed rock road and the second half is the return run downhill. The temperature was reasonable this year at 23F but there was a biting wind that cut through most running gear and costumes. There are a few good and serious runners but most of the participants are more in it for the experience, fun, and a great way to kickoff Thanksgiving in McMurdo.

The finish line of the Turkey Trot in front of the Chapel of the Snows. It is easy to see some of the costumes worn by some of the runners.

These two turkey costumes were new creations for this years Turkey Trot. The two guys made them the night before and stood at the finish line cheering on the runners, including the bullhorn, as the runners finished. The number of 150 participants in the Turkey Trot does not include all of those who volunteered and cheered on during the event to make it a little more special for everybody.

The galley (dining hall) serves multiple Thanksgiving dinners throughout the day. Contrary to most meals, when some people grab their food and leave, the Thanksgiving meal is eaten together as friends. For many of the long time contract workers, their friends and coworkers are closer to them than their actual families. The dining staff has their own meal as a precursor at 12:30 and then they serve meals at 3:00, 5:00, and 7:00. There is another meal closer to midnight for those that are working the night shift. The Thanksgiving meal covers all of the common dishes that you'd see at any Thanksgiving dinner. There are mashed potatoes, sweet potatoes, stuffing, corn, green bean casserole, turkey, gravy, salad, pecan pie, apple pie, and so on. The dining staff do a tremendous job of providing a great meal to the station population. Thanksgiving is also a very unique day in that most everybody cleans up and oftentimes are wearing clothes that are much nicer than you see on just about any other day during the main body season. Sometimes, it can even be difficult to recognize people because you are not used to seeing them look so good and dressed up, at least dressed up for McMurdo.

My Thanksgiving dinner for this year. Except for the wine glass, the dinnerware and utensils are typical of any other meal in the galley. The food is much better than a typical meal in the galley.

It is traditional during each meal sitting for the dining staff to be announced and for them to do a walk through so everybody can thank the dining staff for working and providing such a great meal on Thanksgiving.

My table with coworkers and friends for this year's Thanksgiving dinner.

The Wall Street Journal is in McMurdo for two weeks to cover various aspects of the life and science that occurs here. I've heard word that the WSJ will be having an article on Monday covering the Turkey Trot and Thanksgiving in McMurdo. Be sure to check it out if you have access to the WSJ.

Midway Point

I am one day past the midpoint for this year's field season. It feels much later than that in the season. I think a big reason for that is because we are well over halfway in terms of the work that needs to be done. We have had mostly good weather throughout my time here. The difficult weather conditions that we have had in the last last two weeks have been short lived. The US Antarctic Program uses a rating system of Condition 3 to Condition 1, with 1 being the worst and restricted to no outside movement. I think we have had maybe one day where it was Condition 2 on the ice shelf and snow roads and everything else has been Condition 3. This run of good weather has been very helpful for the station to get caught up from opening the main body season two weeks late due to horrible weather in early October. I am starting to ponder how I am going to handle if I go the entire field season without any fun weather.

There is a chance that we might be able to finish the field season early. I have always felt there was a high probability of this happening this season. The work to do this year, with the maintenance and repair of the Antarctic Precipitation System sites, was anticipated to be reasonable and that has thus far proven to be true. If we do finish early, I am not sure if I'd be able to get on an early northbound flight. There are two flights each of the next two weeks, with my scheduled flight the last of these four flights (Dec. 7). I am hesitant to request to be moved up to an earlier flight until it is certain we will be done early. There is always a chance for bad weather and/or flight delays. Fortunately, I have brought months of work with me so that if we do finish early, I will still have plenty to do here working remotely.

We have been able to get out twice this week to the two local sites. The site at Phoenix Airfield is nearly finished. I estimate about 15 minutes more work to be done at that site. The Willie Field site is dependent on unburying the snow fence shield. We will be having the support of a dozer Sunday night and an excavator all day Monday to assist in removing that equipment. My guess is that it will make for some fun photos. We are also on the schedule tomorrow (Friday) to visit the two remote sites by airplane.

As in the US, we will be having a short work week in recognition of Thanksgiving. Except, how the short week is done is quite different. A typical week for McMurdo Station is six work days and a one day weekend. For Thanksgiving it is a five day work week with Thanksgiving celebrated on Saturday. By late Friday afternoon, things all around town will be shutting down for the long weekend and not much will be happening. In typical Thanksgiving tradition, there will be a turkey trot running race Saturday morning. The galley will also have three sittings for the traditional Thanksgiving meal. It should be a fun weekend.

For all my friends and family in the US, I wish you all a very Happy Thanksgiving and I hope you have great day with family, friends, turkey, and football.

It Takes a Small Town

Frequently, when most people think of the United States Antarctic Program (USAP) they think of scientists going to Antarctica and the work done by the scientists. That is a fair line of thinking given that the objective of the USAP is to advance science and it is funded by the National Science Foundation. The reality is that USAP is made up of far more occupations than scientists and scientists only make up a small percentage of the people in Antarctica as a part of USAP.

McMurdo Station is like a small town. The station population during the summer months ranges from 800 to 1050. Sometimes McMurdo Station is compared to a small mining town and that is a more fitting comparison. McMurdo is located on the tip of Hut Point Peninsula, which is on the southwest end of Ross Island. McMurdo is located on volcanic rock and it is part of the 2% of Antarctica that is not covered by snow and ice. On top of the physical similarities of a mining town, heavy machinery are constantly moving around the town and are a central part of the roads and work areas. Similar to a small town, McMurdo Station is comprised of a range of occupation and workers that fill the wide range of needs in support of the scientific mission.

There is a large range of job titles for people working in Antarctica and at McMurdo Station. There are the typical range of "trades" jobs including electricians, plumbers, carpenters, mechanics, welders, and heavy equipment operators. The people working these jobs are often highly experienced in their field and many are familiar with working similar contract type jobs that last for a duration of the year (not year round). My guess is that people in these jobs are also some of the most veteran people at McMurdo Station. It is not uncommon to find somebody who has been working here for 15 years or more in the trades. There is also a range of more clerical, administrative, and IT positions. The Crary Lab (the main science lab) has a lab supervisor, two assistants, and three IT personnel. There are many other similar jobs throughout McMurdo. A common entry level position for first timers is dining assistants (work in the kitchen, cleaning tables/dishes, etc.), jano (janitorial), and shuttle drivers. These positions are often filled by young people seeking the adventure shortly after college or some people, and sometimes as couples, looking to do something exciting. I should add that frequently the people working these positions are highly educated and these are the jobs they have taken to experience Antarctica. Lastly, there are the support services that are necessary in any town. There is a large number of people that work in "wastes" as they are responsible for packing and retro'ing all of the garbage and recyclables back to California as nothing is dumped in McMurdo Station. There are also people who work at the waste water treatment plant, the station store, lodging, and the list goes on. The scientists are the focus of all that is done here but it is the efforts of a small town of people that allows the science work to be done.

Tall Tower - Part 1

On Tuesday we were able to make a trip to the Tall Tower Antarctic Precipitation  System site. Transportation around Antarctica falls into three categories: wheeled vehicles in McMurdo and on the groomed snow roads to the airfields, tracked vehicles for generally nearby locations on the ice shelf, and by air using helicopter or airplane. Helicopter is used primarily for locations within 50 miles of McMurdo Station and airplane is used for locations beyond that range. The Tall Tower site is about 100 miles to the southeast of McMurdo Station so we took the Twin Otter airplane to do the work on the APS site. The Twin Otter flight to Tall Tower is relatively short as it took about 45 minutes in the air. The Twin Otters are ski equipped so that they can do open field landings. It is really amazing how they can land most anywhere, other than regions where there are crevasses, or cracks in the snow/ice, and it takes very little for them to takeoff.

The APS site at Tall Tower was found to be in relatively good condition. There was one instrument that were buried and needed to be raised. We raised some other equipment as well as there was about 20" of accumulation at this site. The drifting around the site was also quite variable, which is why one of the instruments was buried. The expectation was that this would be one of two trips to Tall Tower with the primary goals for this trip was to evaluate the condition of the site and retrieve an instrument and datalogger to bring back to the lab. Beyond those tasks, we wanted to do any other work that was worth doing on this flight so that we didn't have too much work on the next visit. The big story of for this visit was that the weather was beautiful. When we landed, the temperature was 0F. That might sound cold but when the sun is out, there is no wind, and you are in your cold weather gear, it is very nice conditions to work. It warmed up to 9F by the time we left. The plan was to do two hours of work at the site. At around two hours I talked with the pilot and commented that we'd prefer to get as much work done as we could with the weather so nice. He agreed and we ended up spending four hours at the site. The amount of work for our next visit should be very reasonable to complete and probably doable even if the weather is a little rough. On our second visit to Tall Tower last year we were working in 20 knot winds and it was a challenge.

Beyond the visit to Tall Tower, we took one trip by truck to one of the local sites, Willie Field, and will be doing another later today. The rest of the time this week was spent in the lab in town reviewing the instruments, dataloggers, programs, and the work that needs to be done. Thus far, the weather continues to be moderate to fairly good for this field season.

Trainings and Briefings

Much of the first few week, and especially the first few days after arriving at McMurdo Station, is filled with a series of trainings and briefings. One example is the "Arrival In-brief", which occurs immediately after we are dropped off following the transport from the airfield. There are also individual briefings with groups supporting us during the field season, such as with MacOps - the communications control center. The trainings include: fire, medical, waste, light vehicle (these four are referred to as "core training"), outdoor safety for hiking, and mattrack training to drive the tracked trucks. A new training this year was "Harassment Awareness Training" in response to much of what has occurred during the past year. Afterwards, I had a discussion with one of the senior officials and he said that he'd like to see the harassment training to be more specific to what might happen in the field and among research teams. Overall, I counted 18 different trainings and briefings. We did all but one of them during our first four full days in McMurdo. Our last briefing is with helicopter ops tomorrow to discuss our helicopter support needs. The longest of all of these trainings was the Field Support and Training (FS&T) Antarctic Field Safety course. This course is required for anybody that is leaving McMurdo Station for any length of time and the course is encouraged for everybody. This course is entirely indoors and lasts about four hours.

The current form of the Antarctic Field Safety course is similar to what used to be a refresher course for people working in the field after they had taken "Survival School", also referred to as "Happy Camper School". For years (~15-20 years) the survival school was required for any first year person in the US Antarctic Program who was going into the field. On my first trip, it was required only if you were staying overnight in the field. I did not have to take the course that year as we only did day trips into the field. I was required to take the course when I returned to Antarctica in January 2005. The happy camper school would take about 8-12 people into a nearby location on the ice shelf. The class would consist of building emergency shelters, such as a snow mound or an ice cave, setting up tents, creating a cooking area that is protected from the wind, making dinner, radio comms, and spending the night in a tent, snow mound, or ice cave. I've included some photos from my 2005 training below. It was so much fun! We also had great weather for our happy camper school, which always helps.

The complete project, a snow mound. Looks like a great option for a night of sleep in 2005.

Having dinner in our cutout "kitchen" during the happy camper school in 2005.

Ready for a night of sleep in the snow mound. Keep in mind that there are 24 hour days in Antarctica during the summer field season. This photo was taken at about midnight and bright enough to need sunglasses.

The old rules were that after you completed going through happy camper school, each subsequent year in Antarctica, you had to take a refresher course. About four years ago, the requirement for the happy camper school was eliminated and the refresher course was turned into roughly the field safety course's current form. The training is completed in approximately 3-1/2 hours. It is a mixture of classroom discussion and activities. The classroom lecture and discussion include topics such as risk and safety, cold weather health and injuries - including photos of frostbite, and a video covering helicopter safety. The practical activities are more focused on getting you through a situation where you would be fine if you have to use a "survival bag". The survival bag is gear and food for two people to exist for three days. Survival bags are put on all forms of transportation whenever you leave the maintained snow roads. For example, on today's Twin Otter flight there were two flight crew members and five passengers. Therefore, there had to be four survival bags on the plane. One part of the practical exercises is to go through all of the gear and food that are included in a survival bag. Next we go through how to light the gas stove that is included in the survival bag. Having a stove is one of the keys to survival because melting snow for water to drink is critical. We also learn how to setup the tent provided in the survival bag, and then take a few minutes in groups of 4-5 to set up one of the tents. We even cover some basic knots that would be useful in setting up the emergency shelters. Learning all of this in a nice warm building and out of the wind is far from reality, especially for the situations where you might have to open up a survival bag. However, it is still useful to review mentally and physically some of the tricks to make a difficult situation safe.

The Antarctic safety instructor laying out all of the gear and food in a survival bag.

Groups practicing lighting the Whisperlite stoves that are included in the survival bag.

Practicing setting up tents as a part of the Antarctic safety training. These tents were chosen specifically because of their design with having interior poles. This makes the tents easier to set up from the inside in high winds.

I have never had to use a survival bag. There was one helicopter flight, in strong winds and blowing snow, where before the helicopter left us, we were reminded to not hesitate to use the survival bag. There was another helicopter flight on a beautiful day in the field. However, after a few hours, snowed moved into the region obscuring the visibility. After we were picked up, the helicopter pilot commented that the conditions had nearly deteoriated to the point where he couldn't make out the horizon, necessary for him to land. Overall, it is very rare for a survival bag to be used but the training is done each year so that anybody in the position to do so, will be fine.

Initial Visit to Two APS Sites

When this project was initially proposed, a focus was placed on having two of the Antarctic Precipitation Sites (APSs) within range of being able to drive to the sites. One of the main reasons for this is that it is considerably easier to visit a site by truck or mattrack (a truck with tracked wheels) than by helicopter or Twin Otter airplane. We benefitted from that close proximity last year as we did many visits to the Phoenix and Willie Field sites as we constructed the precipitation systems and made the final engineering decisions and tests. Similarly, the nearby locations benefitted us today as we were able to take the mattrack to visit the same two sites and do an initial evaluation of how the sites survived the Antarctic winter. Two colleagues visited the sites a week ago and had sent us pictures so what we saw was not a complete surprise but it was still different to actually see the sites.

Willie Field APS - Drifting and Accumulation

The obvious feature that is immediately apparent from the Willie Field site is the significant accumulation of snow at the site. In this region of Antarctica, past experience with automatic weather stations is that the area gets about one to two feet of snow accumulation each year. The ice sheets in Antarctica accumulate snow each year and the ice sheets are slowly pushed out towards the ocean. Eventually, the ice sheet calves off into icebergs and drifts away in the ocean. I was expecting this same 1-2 feet of accumulation at Willie Field. Instead, we found about 25-38 inches of accumulation. The range is because the Double Fence Intercomparison Reference (DFIR) shield resulted in significant drifting and accumulation and that accumulation varied throughout the installation. You can roughly think of the DFIR as two rings of wooden snowfences surrounding the precipitation gauge. At installation, not quite a year ago, the top of the DFIR was 78" above the snow surface. There is now only 3" of the DFIR above the snow surface (over six feet of accumulation at the DFIR). In looking at the past observations, it appears that already in mid-March the snow had accumulated to the point where the drifting snow filled the bucket of the precipitation gauge. I've include some photos from a year ago and now to show the changes due to accumulation. The initial task will be to dig out the DFIR and then we'll decide what we should do for this upcoming year.

Phoenix APS - A Wind Shield In Trouble

The good news from the Willie Field APS location is that the wind shields surrounding the precipitation gauges were in very good condition. The double-ring wind shield is designed to slow the winds and increase the ability of the gauge to catch the snow. However, that also means that the wind shields are encountering the significant winds of Antarctica and can take a beating. The wind shields at Willie Field APS survived and looked good. In mid-August, I viewed a video clip of the Phoenix APS site and saw that one of the corners had become disassembled and it was flapping in the wind. I contacted a colleague who was in McMurdo at the time and they visited the site to do a repair hoping to keep the shield intact. Sometime in the last couple weeks, the wind shield at Phoenix had significantly come apart at multiple points and was barely staying together. That is the condition that we found the wind shield today. We lowered the shield and spent about an hour putting it back together and the shield was able to return to much closer to the original condition than I ever imagined with such minimal effort. We'll be going back to this site to do some reinforcing of the joints, and other final details, before raising the wind shield back into place.

Conclusions

Some of the unknowns of this field season were what condition would we find the APS sites and what work will need to be done to repair the sites for a second year of observations. Today, we were able to take an initial visit to two of the sites and I'd classify the results as mixed. There are big questions as to how we'll dig out the DFIR and what we'll do with it for next year. Yet the overall repairs that need to be done seem reasonable. We will now make some decisions on how to go forward with these two sites and then start planning for what we can expect for the two sites accessible by helicopter and Twin Otter airplane.

Never Gets Old

The southbound trip from Christchurch is one that is both a combination of excitement and "been there, done that". I have tried always maintain the same sense of wonder and a feeling of being fortunate on every trip. There is no doubt that those feelings and emotions are not as strong as they were on the early trips, or my WinFly trip from two years ago. However, I still hope that I don't lose sight of the reality that I am traveling to Antarctica and when I get off the plane this place is unlike most everywhere else on Earth. I noticed on this southbound trip that not a lot of people were taking photos. Meanwhile, I was still trying to take photos as I've always done. Unfortunately,  many of the photos look almost the exact same as last year and I'm confident they are not that different from previous years as well.

Waiting in line to check-in at the Antarctic Passenger Terminal in Christchurch.

The day starts with a 4:30 AM wake-up in order to pack and be ready for a 5:15 AM shuttle to the Clothing Distribution Center (CDC) and Antarctic Passenger Terminal (APT), which are located next to the Christchurch International Airport. Once arriving at the CDC, you switch into the required cold weather gear for the flight to Antarctica, as well as do the final packing and preparations to check-in for the flight. All non carry-on luggage is checked-in starting at 6:00 AM. The baggage goes through a security screening process similar to that of a commercial flight and then we have about an hour before we need to return to the APT. That gives us a chance to walk to a local coffee shop or store for breakfast. We return to the APT by 7:30 for another video introducing us to Antarctica and another briefing. From there it is through one last security screening, including removing laptops from the carry on, and then loading a bus to take us onto the tarmac and to the military cargo plane. For this flight we had a C-17, which is about as nice as it gets for a military cargo flight. There are a few flights each year for the US Antarctic Program that use an Airbus or a Boeing 757 but I have yet to have one of those flights. We get off the bus, grabbed a bag lunch, and then boarded the plane for our southbound flight. The flight on Monday had 71 passengers and about 2/3 of the middle of the plane was filled with cargo.

One of the benefits of the C-17 is that it is much faster than the C-130 cargo plane. The flight from Christchurch to Phoenix Airfield took us 5 hours and 10 minutes on Monday. There is not too much to be done during the flight as it is fairly loud. Everybody has either ear plugs or noise cancelling headphones throughout the flight. There is room to stretch out and walk around and that is done frequently. The flight on Monday took off a few minutes early and landed at a little after 2:00 PM, McMurdo time. Because of the close proximity and dependence of the US Antarctic Program on Christchurch, New Zealand, the USAP operates on New Zealand time. With daylight savings this past weekend that means it is plus one day and minus 4 hours, or plus 20 hours, from Colorado time.

Getting off of the airplane is always one of the highlights in going to Antarctica. For this flight we landed with somewhat low cloud ceilings and we could not see as far as is normal when landing. The flight landed at Phoenix Airfield, which is about 15 miles from McMurdo Station. Everybody loaded into a passenger vehicle called the Cress. The Cress is not made for speed and it took an hour to travel from Phoenix Airfield into McMurdo Station where we were greeted by friends when we got off of the Cress and then the arrival briefing, which is yet one of many in the series of trainings and briefings.