All Systems Go and Mid-season Changeover

There is much progress to report, and lots of exciting science happening at Law Dome. First, all of our systems have now been set up and tested. Sharon and Jose have excavated a beautiful 2m-deep trench, which is now the home of the 4-inch drill, the bandsaw and the freezer.

Tanner and Grant drilling in the trench. Photo: Vas

Tanner and Grant promptly set up the 4” drill, which is what will be used to recover the deep (up to ≈240m) preindustrial ice and the air it contains. Andrew set up the ANSTO bandsaw, which produces fantastic straight cuts on our ice cores.

Andrew testing the ANSTO bandsaw with some 4” core. Photo: Vas

The bandsaw will be used for taking a sliver from one of the 4” cores. This continuous sliver of ice will be analyzed for isotopes of H2O and allow us to determine the ages of the ice layers as well as a more accurate history of snow accumulation rate at the site.

The large ice melter (which we’re using to extract lots of old air from the ice, for measurements of carbon – 14 of carbon monoxide) has been performing extremely well, much better than in all of our tests back home in the lab. We have now completed 5 melt-extractions of air from the large BID cores. These samples will help us to understand how much of the carbon – 14 in our samples is due to production by cosmic rays directly in the ice.

We also did a first test of the large melter system with 4” ice cores, to confirm that the drilling and handling process for these smaller cores is equally clean (it is) and works well (it does).

Vas and Peter with 4” cores stored in a side cave. Photo: David E

Vas pulling the clean sled with 4” cores toward the melter. Photo: David E

Loading ice chips into melter bottom (needed for melting to start quickly). Photo: David E

4” core getting its final cleaning prior to the melt. Photo: David E

The large ice melter full of 4” cores. Photo: Vas

It is hard to believe, but the field season is already over for some of us. Vas, David Etheridge, Richard and Andrew left Law Dome 2 days ago for Casey Station, arriving almost exactly at the same time as Ed and David Thornton, who came via a Basler flight from McMurdo station.

The Challenger tractor at a rest stop on our way back to Casey. Photo: Vas

The team is down to 5 up on the Dome (Sharon, Jose, Tanner, Grant and Peter) – they are currently short-staffed, but are doing their best to keep some of the work going. Fingers crossed that the weather holds and Ed and David Thornton are able to get up to the field site quickly!

-Vas

Advertisements

First week at Law Dome

It has been one week on Law Dome for the entire team, and what an incredibly productive week it has been.

We arrived in two teams, with an advance group of 5 people heading up the dome November 20th with much of the camp and science cargo. As they battled snow and wind to get all the equipment to our new camp, “DE08-OH,” the rest of us were trapped 130 km away at Casey Station due to bad weather. The three-day blizzard at Casey peaked with winds of 70 knots and a maximum gust of 94 knots!

After a long, snowy, bumpy ride up the ice dome in two tracked Hagglunds, we were all finally united.

The science team on their 10-hour long traverse from Casey to DE08-OH.

Camp living structures shortly after arriving.

Once at camp, everyone was eager to move temperature-sensitive cargo into tents (heroically erected in gale-force wind and blowing snow by the advance team). Making a long story of unpacking boxes short, we went from a 3-day blizzard to having most of our equipment set up in structures 3 days later.

Excitedly unloading science cargo after finally getting to camp.

Ice coring with the US 3” Eclipse drill has progressed to 60 m depth, with firn-air sampling from the surface to capture how the layers of snow trap air as they are compressed into ice.

The Eclipse and firn-air tent.

David Etheridge and Lenneke Jong excited to see the first ice core of the season!

The “ice melter” is safely at home in its melter shelter (or “melta shelta,” depending on your accent). This protective wooden box was put up in 2 days by AAD carpenter Brett, handily assisted by our traverse drivers Juan and Shane from Casey Station.

The science tent and melter shelter, with the large-volume ice extraction “ice melter” inside.

We have fully set up this system and as of December 6th have successfully undertaken our first tests with large ice cores (24 cm diameter, 1 meter long) drilled using the US Blue Ice Drill. The BID is at home in what we call “driller heaven,” a heavenly white tent that should make the operation weatherproof.

A peek inside the Blue Ice Drill tent, where large ice cores are drilled.

The latest project is excavating a trench to house one more drill, the US 4-inch system. The trench is marked out and the snowblowers are getting to work.

The 4-inch drill trench in the process of being marked out. The Blue Ice Drill tent is in the background.

We hope everyone back home is having a great winter. If you’re dealing with snowy weather, we can relate down here on the wet side of Law Dome!

Ready and waiting…

410 words (2-3 minutes)

It’s (for the most part) been a busy two weeks at Casey Station! We now have about half of the team up at Law Dome, moving heavy sleds of equipment from a depot near the dome summit to our now camp–dubbed “DE08-OH.”

LawDome_DE08OHx copy.png

The traverse route up Law Dome. The advance team is currently shuttling equipment between a depot at D-28 and our new camp, DE08-OH. Map data are from the Reference Elevation Map of Antarctica, plotted with QGIS and Quantarctica.

DE08 was an ice core site used by our team member David Etheridge and others to reconstruct past atmospheric CO2 and CH4 (methane) concentrations. This site remains one of the best linkages between modern measurements of atmospheric greenhouse gases, and the ice core record. We are going there again to take advantage of its high snowfall (a fact the advance team may be regretting as they wade through snow…) to shield our samples from too much in-situ Carbon-14 produced by cosmic ray bombardment .

The rest of the team remains at Casey Station, in part to keep the camp population manageable before several tents are erected. We also have more sensitive science equipment back here with us which cannot freeze, so we need warm structures at the site before heading up.

Over the last week or so, we completed our survival training, which was a great combination of hiking out in the sun and snow, watching Adelie penguins, and sleeping out with only the survival gear that we are required to carry whenever we leave station. It’s a minimal setup, including only a “bivy” bag, sleeping bag, and mat to sleep in. But with emergency cold weather clothing, this was still quite comfortable.

IMG_7561

A cold, beautiful night at survival camp.

IMG_7505

Adelie penguins wallowing in the snow on Shirley Island.

IMG_7488

Part of the Shirley Island Adelie penguin colony, including what looks to be a new species: the rock-lier penguin (get it?).

For now, those of us still on station remain ready to drive up Law Dome as soon as possible–hopefully in the next two days. The support from Casey Station has so far been amazing. We are rested, eating too much, and are eager to get to work setting up camp and science equipment at DE08-OH on Law Dome!

Oh, and Happy Thanksgiving! Again, we’re eating plenty of food here…

-Peter

For another perspective on the project, check out this recent article from Nature News! You can also follow Peter’s posts on Twitter, under the hashtag #LawDome1819.