This week at Casey: 21 November 2014

Forty-four summer expeditioners arrived at Casey last Wednesday via Hercules, after being held up at McMurdo station (part of the US Antarctic Program) for one to three weeks due to poor flying conditions. They were treated to a warm welcome by the 2014 winterers and settled in over vibrant discussions of their time visiting the Americans at McMurdo and New Zealanders on Scott base.

Both stations sit on Ross Island under the ever watchful gaze of Mt Erebus, a volcano which has been visibly active since 1972.

McMurdo was full capacity when the expeditioners arrived at over 1000 personnel with the US summer crew mostly transiting to staff their projects at the South Pole and WAIS Divide. The locals were friendly and the Casey group transitioned into Antarctic life over the week with prompt engagement in meal times and attending invitations to observe science in the Crary science building, diving operations, off-site NASA camp and hospitality at Scott base. Scott base was a pleasant three kilometre stroll from McMurdo, offering a smaller population of several 100 personnel and a great souvenir shop!

There were great hikes available with a short walk out of “Mac Town” to Scott’s hut, established in 1902 with his fated South Pole expedition, to inland treks to Castle Rock. Observation Hill, just above McMurdo, allowed for amazing panoramas and the chance to pull out the boot chains to reduce the risk of slipping on the compacted snow.

The expeditioners were grateful for the hospitality and warm welcome received from their hosts, but relieved when the fine weather complimented the Hercules flight from McMurdo to Casey on the Wednesday, so the summer season could kickstart at Casey!

Dr Lizzie Elliott

Every season at the start of summer the plant operators at Casey face the challenge of opening the wharf road to traffic. The wharf road only comes into existence after being carved into the deep recess of Thala Valley after the long winter. Casey station was re-established to the south and across from the old station and wharf in the 1980s and, while the position was more favourable, the challenge remains each season to excavate the road and establish the link before the annual resupply.

This season Glenn and Johan set to it with a bulldozer and excavator to carve out the road that follows the valley floor leaving ice walls up to eight metres high in places. 

Joe 

A few weeks back the Casey station news reported a frozen spring observed on the ice plateau above Robinson Ridge. This feature has since been recognised as evidence of a jökulhlaup that probably occurred during late summer of 2014.

Jökulhlaup is an Icelandic word describing an event where water dammed by a glacier is suddenly released. In this case the water has been trapped beneath the ice sheet and can be termed a sub-glacial outburst.

The topographic features visible through the winter months mark only the second occurrence of a jökulhlaup recorded on the Antarctic continent, the first having been witnessed above the Clark Peninsula (also close to Casey) in 1985 (I.D. Goodwin, 1988). In that case the water flowed sporadically for several months over two summer seasons.

The discolouration of the water that flowed from the Robinson Ridge subglacial outburst indicates, as in the 1985 event, the water carries with it a significant sediment content.

During this coming summer the plan is to sample this ice to see if, like the previous event, the water released originated as basal melt water that has been squeezed through subglacial sediments over a long period of time.

The protruding geyser-like features noted initially last summer have now worn down and ablated. However, they are still recognisable as something quite different on the ice sheet margin, as the following pictures show.

A few weeks ago, Ian, Steve B and Grant headed out on a five day trip to all the huts around Casey. The aim of this trip was to clean and restock, change over the emergency ration packs and medical equipment, and check fuel and gas supplies. One of the other benefits of a trip like this is the opportunity to spend a decent amount of time off station exploring the area just before the summer crew arrives and station life becomes very busy.

Loaded with plenty of supplies we headed off on Sunday and to our first overnight stop at Kenny’s hut. We arrived just in time to restock and have a quick look around the surrounding area before the bad weather set in for the night. By the following morning the wind had settled a little so we set off for Robinson Ridge hut for lunch and then Browning Peninsula hut for the next two nights. Browning peninsula is still my favourite area around Casey, with amazing scenery over the islands and Vanderford Glacier, and the opportunity to hike over to Peterson Island where the US first landed back in 1948.

After two days of work and exploring we headed off for Jacks Donga for our fourth overnight stop. Our last day saw us travelling to Wilkes Hilton where we also performed some maintenance on nearby penguin colony cameras.

We all had a great time and saw some of the beautiful and less visited areas around Casey, and now hopefully our new arrivals can get out and enjoy the clean and well stocked huts over the summer.

Grant