Lake Bonney Expedition 2008
The first deployment is under way.
Here are the first week's blog entries from Vickie Siegel.
For the most recent entries see the bonney 08 blog
The gantry and hoist are set up inside our completed tent
Maciek starts the melting coil on the refrozen cap on our melt hole. The steam generated from this made the Bot House into a sauna for a few minutes
Once the melter punched through the frozen cap, Maciek and John worked on chipping out some of the ice around the sides of the hole
The Bot House is open for business! Bob, Vickie, Shilpa, Bart and Peter (left to right) pose in front of the haven
The commute back home after a satisfying day
December 2, 2008
What a difference a day makes. Kristof was the first one up and about this morning and he immediately set out on a mission. He drove the ATV from our somewhat sheltered camp on the shore to our Bot House site on the ice. After a brief stop at the platform to assess the situation, he returned to camp directly to report his findings. The rest of us awoke to the sound of two cooking pots banging together and Kristof shouting, “Everybody up! The wind has died down! Let’s get to work!”
We were all still exhausted from our efforts yesterday but this news rousted us from our sleeping bags. As we hurriedly ate our breakfasts and gulped down some of Bob’s coffee we wondered, “Can we do it? Can we get the rest of the tent up before the wind kicks in again?”
We marched out to the melt hole and found that yes, it was much calmer out there. But was it enough? With trepidation unpacked the liner tarp and once again we tied on the ropes and tossed them over the frame. With the first few tugs on the ropes we found that things really were much easier. We had the liner tarp up and secured and the end walls in place in no time. We had just started to pull the middle insulating layers onto the tent when a helo carrying our carpenter friends from McMurdo arrived to help us. From there on out the Bot House was abuzz with productivity. It was difficult to even keep track of all the activities that were happening simultaneously — the insulating blankets and outer cover were pulled over the tent and secured, inside, the bot’s lifting gantry and hoist were assembled, electrical outlets were installed, heaters were brought in and propane tanks were staged outside, generators were set up, communications technicians arrived and set us up with solar powered wireless internet, the crust of ice that had refrozen on the surface of the hole was melted and chipped out, stairs up to the front door were installed, shipping containers full of our equipment were sorted and the contents brought inside, and finally the shipping containers themselves were pulled in close against the outside walls and secured with cargo straps to ensure that nothing could blow away.
We look on nervously as the helo lowers the bot onto our Bot House platform
Members of the team work together to construct the final pipe arches (there are 17 total) of the tent frame
With the frame completed we begin to unroll the liner tarp on the up wind side of the structure. We plan to tie ropes to one edge and pull it over the frame to tie off on the downwind side
This quick photo, the only one snapped during our epic battle, does little to convey the chaos of the gusting wind and the tarp that threatened to carry us all away
December 1, 2008
In accordance with our hopes, the winds died down enough by this morning that helos were flying today. In addition to the much-anticipated delivery of the bot we were expecting several other sling loads, include the final bits of plywood for the bot house floor and the roll-away cover for the melt hole, now referred to as the moon pool. These items arrived first thing in the morning and we wasted no time getting everything in place. The next sling load to come over the horizon was a black oval with yellow feet and flame-decaled yellow fins. Everyone scurried to pull out their cameras and hunker down behind the various large shipping crates that are scattered around the platform. With a 2000 lb sling load a 212 helo creates a tremendous amount of rotor wash and certainly a lot of noise. The physical turbulence made the emotional rush of seeing the pilot set the bot squarely down on the platform all the more exhilarating. The pilot unclipped the cable and thundered off. Now it was time to get to work.
The next step on our agenda was to build the polar haven tent structure of the Bot House around the bot. We learned the procedure in McMurdo: assemble the pipe arches and walls that make up the frame of the haven, pull the insulated blankets (tarps) on the end walls, pull liner a tarp over the arches and tie it down to the floor on either side, on top of this go insulating layers over the arches and then finally a large, weather resistant cover goes over it all. Our entire practice run in McMurdo took 6 hours.
Things started off well enough. Though it was slightly breezy, we made quick process in constructing the pipe frame. Two people worked from the top of some scaffolding and the rest scrambled around arranging pipes and fitting them together. Over the course of the afternoon the wind began to build but in our concern to get a shelter built over the bot we didn’t take much notice - yet. Once the frame was together we pulled out the liner tarp and prepared to install it on the 16’ tall frame. We lined the tarp up on the ground along one side of the arches and tied ropes to one edge of the fabric. Then we threw the other end of each rope over the entire frame to people standing on the other side of the structure. Half of the team pulls the ropes to drag the tarp up and over the arches while the other half feeds the tarp up and manages any snags that occur. This is when we really noticed the wind. We were trying to pull the tarp from the upwind side of the structure to the downwind but the force from the wind meant that the tarp simply pressed against the pipe frame with enough pressure that it was incredibly difficult to drag it up to the peak and over. Once we did get it over the top, everything got worse. With no wall to press into, the downwind end of the tarp whipped up violently against the 4 ropes we had tied to it. It became a sail. Helpers jumped in to assist the rope haulers, who were nearly being whisked away on the ends of their ropes. The points where we had tied the ropes on the tarp began to rip through, giving the raging beast a greater range for its erratic motions. With the whipping and cracking of the tarp, the gusting wind, and our layers of hats and hoods, shouts and instructions were snuffed out. This was the stuff of epic sea chanteys, not field robotics. Somehow we managed to tie down, at least marginally, both sides of the tarp. Worried that the liner tarp would rip further unless we put up the end wall tarps quickly, we plunged into this next struggle. By now we had been working on the tent for about 8 hours. After some time spent fighting more of the same battle with the first end wall, Peter made the call that we were in a losing battle, the wind was just too strong. The rest wearily agreed and after the equally arduous task of removing the tarps from the frame and corralling the unruly masses of fabric back into boxes for the night we dragged ourselves back to camp. Sometimes it’s just best to try again tomorrow.
This diagram by Hannes Grobe was copied from the Wikipedia page on katabatic wind.
November 30, 2008
Since our next moves can only happen after the bot is delivered tomorrow, today was a natural day to just take a break. The winds continued to barrel down the valley but some folks decided to take the free time as a chance to do some hiking anyhow. The others caught up on office work, read books and drank cocoa. Around the dinner table Peter explained the origins of the incredible wind we’ve been experiencing. The Antarctic continent is shaped like a giant dome, more or less. The land in the interior of the continent is covered with a massive ice sheet over two kilometers thick and the highest elevation of this dome is around the center of the continent. During the winter the rock and ice radiate their heat out to space and temperature drops. As the land cools, the air does, too. The air grows denser as it cools and gravity starts to drive it downhill. The phenomenon is called a katabatic wind and in Antarctica they are known to be fierce, cold and persistent.
Hiking from Blood Falls Camp to Lake Bonney camp, Vickie and Bill found several mummified seals on the ice
Everyone relaxes after Thanksgiving dinner in the Lake Bonney jamesway
November 29, 2008
In US Antarctic Program tradition, Thanksgiving is celebrated the Saturday after the actual holiday so that everyone gets a long weekend, both Saturday and Sunday off work! Of course, we are hardly the sort of people to argue with that kind of a tradition and we had an invitation from John and the folks at the Lake Bonney camp to join them for turkey dinner. Around midday we headed over to the camp on the east lobe of Lake Bonney. Most folks opted for the 20 minute ATV ride to the camp and Bill and Vickie decided to walk. Along the way they came across several mummified seals. For unknown reasons, seals and penguins occasionally wander away from the sea and travel up the Dry Valleys. A long way from home and with no chance of finding food in the barren valleys, these animals die before finding their way back. Since there are no insects to consume them and the climate is extremely dry and cold, the corpses remain remarkably intact for years.
The last stragglers arrived at Lake Bonney Camp just as the turkeys were coming out of the oven. Noshing away on our stuffing and sweet potatoes we admired our surroundings. Unlike our camp at Blood Falls, the Lake Bonney is a permanent installation that is used every season. It is larger than our camp, with several large tents in addition to personal sleeping tents and a 15’ x 40’ Jamesway building which is the kitchen and community space for the group there. Also they have WiFi. It was field camp nirvana. After thoroughly enjoying the good food and good company provided by the Bonney Camp researchers we took ATVs back to Blood Falls for the night.
The trombone melter in the pilot hole we drilled.
Peter, Bill and Maciek mark the perimeter of the 8’ diameter hole we will melt out.
November 28, 2008
Things have been going very well with our field work for the last two days—the weather has been pleasant, we made good progress on the Bot House platform and we’ve even had some tasty camp dinners in our mess tent. One could almost forget we’re in Antarctica… Well, today we got a little reminder. Late last night several of us woke up to find the walls of our tents whipping and popping in our faces, straining against the tent poles. The mild wind from yesterday has built up into violent gusts and from what we hear on the VHF radio, the weather in McMurdo is deteriorating, too. As a result, no helos are flying today and the official operations in McMurdo, helo and otherwise, will be shut down Saturday and Sunday for the Thanksgiving holiday. After all our rush, the bot won’t be delivered until Monday.
Of course in the field there is always work that needs to be done so we used our new-found free time to work on mission planning and choose the spot for our second melt hole. Lake Bonney lies in the bottom of the Taylor Valley and the lake’s shape is dictated by the valley walls. It is narrow and long, too long for us to drive the vehicle to all points in the west lobe of the lake from a single point so we will work from two different ice holes — one close to the Taylor Glacier face and the second further east. About halfway through our field work schedule we will move the bot house to the second hole but first we need to make the hole.
To initiate us as true scientists in the Dry Valleys, Peter decided that we needed to drill the pilot hole in the ice. Annika was our designated “drill sergeant” and showed us how to operate the Jiffy drill, a machine that requires two people and a drill bit 10 inches in diameter. After we drilled the hole, Peter, Maciek and John Priscu returned and helped us place a melter in our pilot hole. Someone has to return to refuel the generator here every 4 or 5 hours and in two days we should have another 8’ hole in the ice.
Peter and Bill level the timbers.
The 8x8 timbers are in place and ready for the floor panels
Moving the floor panels with the ATV was much easier than lifting them
Peter drills holes in the ice to anchor the platform
A completed floor at the end of the day
November 27, 2008
We returned to the floor supports we placed yesterday. To ensure that our finished floor sits level, Bill and Peter took some time to measure the height of each floor support as the others placed the 8”x8” timbers that hold the floor panels. With their measurements, we shimmed some of the timbers with plywood to bring them to the proper height. The 8x8’s are held in place end to end by steel moment plates. We attached these and then added 2x4 spacers that keep the four rows of 8x8’s parallel.
With the 8x8 timbers in place, our next move was to start placing floor panels. During our test-build of the Bot House in McMurdo, we learned that the floor panels are heavy (~500 lbs), but manageable when many people work together to lift them. The difference between our test build and the real thing, however, is that here we are working on the uneven and slick surface of the lake ice instead of the flat gravel yard at McMurdo. Slowly and cautiously, we inched the first few platform sections across the ice until Maciek brought our attention to another tool we have at our disposal here: the ATV. The new procedure became to have several lifters carefully place a platform section onto the bed of the ATV and then walk alongside the vehicle to make sure it didn’t slide off the bed as someone drove the ATV to the platform - in - construction. From there it was easy to transfer the section from the ATV to the 8x8’s.
As one crew moved the floor sections into place, other folks worked to line the panels up and bolt them to each other. Then the floor sections needed to be anchored to the ice. For this Peter drilled 2 holes into the ice at the end of each panel. The holes intersected under the surface in a V - configuration. We threaded rope through the ice holes and tied off to eye bolts in the sides of panels. The finishing touch for the day was to secure the base frame of the tent to the edge of the floor.
We are ready to build the tent after the bot arrives tomorrow!
A sling load and our duffel bags on the shore of Lake Bonney, at Blood Falls Camp
Bob, Bill and Bart decide where to place the floor supports around our ice hole. A couple inches of ice have refrozen on the water surface, making it safer for us to work around the hole
Bob and Kristof unwrap a lumber sling load on the lake ice. The yellow wings are placed on the sling loads by the helo techs to stop the load from spinning as the helicopter flies through the air.
November 26, 2008
Our first day in the field! This morning we started off by enjoying our last prepared breakfast in the McMurdo Station dining hall and then checked out of our rooms and headed down to the helo pad for our flight to the west lobe of Lake Bonney. The plan was that Peter, Bill, Kristof, Bob, Annika, Maciek and Vickie would head out to the Blood Falls campsite and start to set up the Bot House platform on the lake ice. Chris and Shilpa would join us in the field on Friday. Maciek and Annika left town on the first flight to run some errands at the Lake Bonney camp before the rest of us arrived. After we selected our helmets and weighed ourselves, the helo technicians loaded our duffel bags into the Huey and we all squished into the remaining seats. The rhythmic thud of the rotors accelerated and we were carried over the white expanse of the Ross Ice Shelf and into the stark grey granite walls of the Taylor Valley.
After the scenic 40 minute flight we arrived at the Blood Falls Camp site, named for the dark orange streaks in the iron stained glacier nearby. McMurdo carpenters had already set up two small weather haven tents for us and a couple helo sling loads of our camp gear had already been delivered that morning. We took a couple of hours to set up camp. We decided to use the smaller weather haven as a kitchen and the larger red haven as a dining room. We set up our tables and chairs, moved food into the kitchen and set up our personal tents.
After a quick lunch we walked out to the 8’ diameter ice hole that Maciek and Annika melted for us last week. For a quarter mile radius around the hole, the ice was strewn with sling loads of our gear—lumber, tools, drums of fuel, and the wood panels that will make up the floor of our Bot House. The first task was to unload some of the tool boxes and lumber pallets. Once we had some tape measures in hand we were ready to start real work towards building the platform. Over the course of the afternoon we surveyed out the locations for the floor supports, stopping occasionally to duck low when additional helo deliveries arrived. By evening all of the floor supports were in place. The last sling load was set on the ice just as we all crawled into our tents for the night.