Stone Aerospace

The Field Team Shrinks

A cardboard cutout airplane marks our current position on a strip chart posted at the front of the C-17 and updated periodically by the flight crew. (photo: Peter Kimball)

Yesterday was an emotional day as Justin and I departed Antarctica, leaving the rest of the SIMPLE field team to finish out the season. We’re hitting full stride with ARTEMIS now, but there are several key challenges still standing between the team and the data we’d like to collect before the end of the season – a tough time to walk away.

From the States, I’ll be starting to write up our results for submission to the academic literature. I’ll also be catching up on a few blog posts I wasn’t able to make from the field and reading along whenever Evan and Kristof are able to post from the front lines.

We sat on the C-17 with our new glaciochemist friends from Michigan (check out their field work here). Generally, the homeward bound on board were exhausted, but satisfied and excited to see family. At cruising altitude, folks got up and wandered around the aircraft, peering out the windows and stretching out to nap in the mostly empty cargo area. At the beginning of the flight, we watched the sea ice give way to open ocean. Just before landing in New Zealand, we watched the sun set for the first time in weeks.

Reporting by Peter Kimball

Camp Takedown

Today we took down what remained of SIMPLE camp – disassembling the Bot House, loading everything into crates, and hauling things off the ice in sleds. It was amazing how many details there were, how many different things had to come together to make this project work. Dismantling it all was a reminder of everything we had put together in the past few months, all of the hard work and support that got us here. We had been having glorious sunny weather for the past few weeks, but today the wind and chill picked up again, as if even Antarctica was bidding us farewell, saying “Remember who I really am!”

We especially want to thank all the USAP personnel who helped us during this project. From the carpenters who built and un-built our camp structures, to the divers who helped us with underwater logistics (and rescued us), to the Fuelies who kept us warm and resupplied with fuel, to Fleet Ops who had our back for all heavy lifting needs, to the stewards in the galley who kept us well fed – truly we could not have done any of it without all of you.

Also a huge shoutout to Dave Matson, our project mechanic from the MEC. You kept our camp running even when nothing else would.

One last view of Ross Island and McMurdo Station from SIMPLE camp. (Photo: Evan Clark).

Reporting by Evan Clark

The Final Mission

Today was a bittersweet day, as it was ARTEMIS’ final mission of the season. The sea ice conditions dictate that we must be completely cleared off the ice by Friday morning. After our previous long sea ice mission, we only had about 4.4 km of fiber remaining – not enough for another long mission. So we decided the best return on our remaining resources would be to conduct one last mission on the safety line investigating the sea ice / ice shelf transition in detail, which is well within our 1 km on-safety-line operational radius.

For those who need a refresher, an ice shelf is glacial ice that formed on land and flowed off the continent to float on the ocean. The portion that is still on land is called the ice sheet, and the portion floating on the ocean is the ice shelf. Ice shelves are much thicker than sea ice, and their buoyancy helps support the weight of the ice sheets (glaciers) on land. This is why people are worried about them melting – if an ice shelf collapses, all the glaciers it holds up are free to slide into the ocean, which could raise global sea levels significantly in a short amount of time (meters, in the case of the West Antarctic Ice Sheet). It is a common misconception that melting icebergs raise sea level, but this isn’t true. Try putting a piece of ice in a glass of water and letting it melt – it doesn’t change the water level! What scientists are worried about is new ice entering the ocean because the ice shelves are no longer holding up the ice sheets.

Sea ice is ice that formed from the ocean itself, and is much thinner than an ice shelf. Sea ice more or less melts and reforms every year with the seasons (there are some places with multi-year sea ice that does not melt completely). Our camp is on sea ice so that we can more easily drill through it to give ARTEMIS access to the ocean beneath, but this also means our season must end once it is no longer safe to be out and about on the melting sea ice. We really don’t want to fall in!

We conducted several zig-zag transects across the ice shelf transition with water samples along the way. Some of these transects were as close as possible to the ice ceiling to gather fine-grained sonar and imaging data, and some were further away to gather “patch tests” to help us determine the precise physical misalignment between the robot’s navigational center and our acoustic mapping instruments, which will help us improve the quality of our maps in post-processing. I really enjoyed this mission because I got to fly ARTEMIS super close to the ice with challenging topography, Mark was stoked about the patch test data, which he has been thinking about for years, and Britney was excited about all the ice interaction science. We were all fascinated by the fact that this and every other time we have passed the transition, we have seen a huge abundance of wildlife (fish, shrimp, jellies) hanging out here compared to other places. Why do they like it here? We don’t really know. But understanding why might help explain some dynamics of ecosystems in ice-covered environments, which in turn could inform our search for life in Europa’s ocean.

A last view of ARTEMIS under the sea ice near the borehole during the final mission. (Photo: Bill Stone).

The next few days will be tearing down what remains of camp, hauling it back to town, and starting the long packing process to ship it off the continent. Brian, Luke, and I leave on Thursday, and most of the rest of the crew leaves on the 17th. We’ll miss this place, the people, the adventure, and the beautiful things we’ve had the opportunity to witness through ARTEMIS’ eyes.

Reporting by Evan Clark

One Day Back In September

I was able to post most of my most interesting photos from the field… with this major exception. One day back in September, before ARTEMIS was on station and before SIMPLE camp was fully established, John and I rode with Kevin and Gretchen to the ice edge to north of McMurdo. Kevin and Gretchen are plankton researchers who collect samples at the ice edge regularly. We took the opportunity to ride along with them to record the locations of the ice edge and nearby hazards in case they became relevant in an ARTEMIS “armageddon scenario”.

The sky was overcast in a slightly spooky way, but visibility was still good, and the terrain was breathtaking. We drove along the Cape Evans Route past the Dellbridge Islands, past an iceberg frozen into the sea ice, to the sea ice edge at the foot of Barne Glacier. The day was remarkable, but I didn’t get the chance to process the photos and put up a post until now.

At the ice edge, John and I were recording positions and Gretchen and Kevin were debating whether to deploy their sampling gear in the growing winds when three black dots appeared at a distant spot on the ice edge and began heading straight for us – Emperor Penguins. I took some photos as they approached us, looked at us and our Pisten Bully for a few minutes, and then moved along to other penguin business.

Before heading home, we looked east at the beautiful Barne Glacier – water that has been frozen solid for 2000 years (i.e. since the time of Christ) flowing down the slopes of Mt. Erebus and into the Ross Sea. The glacier ends in a mind-bending ice cliff with Weddell seals hauled out on the cracked sea ice at the bottom.

The Barne Glacier flows into the Ross Sea from the slopes of Mt. Erebus. The glacier dwarfs Gretchen’s Pisten Bully in this photo. Mt. Erebus is obscured by clouds in the background. (photo: Peter Kimball)

On the way home, we had to stop as a group of around 15 Emperor Penguins crossed the route, marching over the sea ice toward Hut Point Peninsula on Ross Island.

Emperor Penguins march across sea ice, far from open water. (photo: Peter Kimball)

John sleeps in the back of the Pisten Bully, exhausted from an amazing day. (photo: Peter Kimball)

Reporting by Peter Kimball

The Beginning of the End

We are nearing the end of our field season. The ice is getting thinner, and soon it will not be safe to drive vehicles out onto the sea ice because of the danger of falling through. We’ve had a run of warm and sunny days in the last week, and it’s amazing how fast the ice changes since it’s daylight 24 hours. We are now driving over potholes filled with water, and it is especially pronounced near the transitions from sea to land, where the pressure of the ice hitting land causes fracturing, and fine volcanic particles tracked out onto the ice by vehicles leaving town darken the surface and accelerate melting. You almost need a helmet when riding in the Pisten Bully because you can be bounced right into the ceiling!

Our camp takedown began on Saturday, when our fish hut was pulled off the ice, and the culvert below it was removed. Mel from fleet ops came out in his Challenger bulldozer to do the heavy lifting and hauling. It’s sad to see it go – this was our project’s first portal to the world beneath the McMurdo Sound, and both Bill and Sunfish performed many successful dives through this hole. All remaining dives will go through the main borehole in the bothouse.

Other structures and pieces of big gear are following piecemeal. The Tweety Tent (galley) will be removed on Tuesday. Everything else, including the bothouse, will be completely off the ice by Friday Dec 11th. We will run a few more missions in the meantime, but the sense is definitely that things are winding down.

We also took down our tents, so no more sleeping out at the SIMPLE site. Goodbye, camp life, we’ll miss your beautiful vistas!

We’ll miss the beautiful views from camp. (photo: Evan Clark)

Reporting by Evan Clark