A day in the field

I've been writing a lot about what fun activities and adventures have been available during my free time down here, but not so much about what fills my day-to-day life at work. So here's a bit of an overview of what a typical diving work day would be.

Our morning start times on FOCE depend mostly on whether we are diving off of our “trusty” work boat the Pagadroma, or driving out to our sea-ice site at O'Brian's Bay (I'll just refer to this as OB1 to make things easier) where the ant-FOCE experiement has been set up for nearly 3 months now.

Sunrise clouds

When we work off the Pagadroma we need to be up and running a bit earlier so as to be back at the wharf before the tradies knock off. This early start comes with the wonderful opportunity to catch some stunning sunrises from the boat, even if it eats about an hour off of my sleep-time.

One of the other mind-blowing things we've gotten to see from the boat is the ocean freezing over. The water will slowly start to freeze from the top down on particularly calm cold nights, forming a layer of “grease ice” on the surface, which I have seen get up to approx 5mm thick.  

This ice is easily displaced by the boat cutting through it, sliding layers over each-other on it's way. Here I was thinking I had seen the ocean in most of it's states, yet the idea that it can freeze over is quite striking. Seems a bit silly this should come as a surprise seeing as we have been working on and below sea ice for the last 4 months,but it something different to actually observe it forming.

When our work is land and sea-ice based, we have a more or less exciting commute by Hägglund (hereby “Hag”) to OB1 along charted and GPS routes, travelling across large ice-flows and along glacial moraine lines.

When I say more or less exciting this is because the conditions of the track are so incredibly weather dependent that it has taken us everywhere from 30minutes to over 2 hours to cover the same trip. Some days the ice has melted away to form very consequential melt-streams (frankly I'd call them rivers...) into which the Hag will drop of the quad bikes will get bogged.

melt "stream"

Some of the terrain we'd be regularly driving through on a warm day

There are also days when the visibility has been greatly reduced due to snow and wind, and though we avoid travelling to site on these days, it is not always possible. On a good day though, the snow is hard and the sun shining and we only get stopped in our commute to take photos of the breathtaking scenery or have the occasional snowball fight. 

Once at the dive site, there is a more of less extensive set-up process, mostly depending on whether we forgot to bring the music radio with us and whether it has snowed since we last got out to our dive hole.

drilling dive holes

original formation of dive hole

 

The hole was originally cut into the ice using a 90cm augur on a precarious little machine, but has now grown to the size of a small swimming pool due to our repeated travel through it and all the bubbles we have been blowing. 

current dive hole dimensions- just chillin'

                We set up all our gear and clear the fresh ice and snow off of our hole (if we can find it!), finish setting up any remaining scientific equipment and get our divers dressed in. What does one wear in -1.8°C water you might ask? 

dive gear at the wharf on a particularly snowy day

While we all wear slightly different amounts under our drysuits, most will wear some variation of the following: Merino wool thermal under garments (in my case two pairs of leggings!), some fleece pants and top, a “wooly bear” onesie (really fuzzy onesie), about 2 or 3 pairs of thick wool socks(or my boot-liners :) ), and the drysuit. The drysuits we wear are fitted with dry gloves as well, so we pile on a few layers of fleece under-gloves before popping those on. 

diver checks done before every single dive

Once our drysuit is zipped up and our beanie comfortably in place, we can start getting the dive gear onto our divers. With ankle-weights in place and occasionally an additional weight-belt, we can start the heavy lifting. This involves one (ideally two) people hoisting the BCD-harness system onto the diver's back and proceeding to do up the multitude of clips and connections to hold it in place, and connect the drysuit to it's air-source.

We fit the dry gloves to our diver, put fins on his feet while he stands there trying to keep his balance, make sure he has a knife and a dive computer, and lastly place the weights into the BCD. We've estimated the diver is wearing approx 35kg of weight on his body by the time we are ready for final checks! The last step in this process is a strict militaristic check of all of the diver's equipment, starting with the bailout tank on his back, checking everything from drysuit zippers to how happy the diver is (by the time this question comes around at the end of the checks the answer usually involves and impatient grumble to please be let into the water).

Finally entering the water (Christmas eve, hence the hats :) ) 

Once cleared by the dive supervisor, both divers enter the water, rejoicing in the immediate alleviation of all the weight they have been carrying and with any additional science gear in hand, perform a few last minute checks on each-other and take off to their respective tasks. 

Standard view for tenders: umbilicals and ice. 

At this point the surface crew (one tender for each diver, the dive supervisor, and often an additional person to do the running around helping part) either get to relax and stare at some hoses going into a hole in the ice, or start a frantic ballet of hoisting ropes carrying samples from the divers and expensive gear to and from the bottom of the shotline (a rope we have permanently attached at the hole's edge for a variety of useful purposes).

diver leaving surface as seen through the hole

 

Under the ice and out of sight of the supervisor, the divers are able to talk to each-other and to the surface crew through the use of full-face masks and communication cables. This is intended to make things a lot easier in terms of communicating instructions and keeping safety a priority, even though at times it seems to just make things a little more confusing.

The divers are performing a variety of tasks, sometimes taking sediment cores (pushing a PVC pipe into the sediment and capping it so as to bring up a specific amount of it for various tests), sometimes simply checking the condition of our experimental set-up, and sometime setting up and taking down miniature versions of the experiment for the PhD student amongst us, or taking photos along specific transect lines. 

Under the ice, the world moves at a different pace. We joke about how the pressure difference somehow condenses time underwater (it just seems to fly by), and also condense brains. It's well known that all the divers, no matter how much they've discussed and checked plans before submerging, seem to have some vague amnesia of actual instructions. But that might be partially due to the setting in which they are which is frankly amazing (

Diver on safety stop seen from the Pagadroma
- Casey Station in the background

though at some sites quite dark, dull and outright boring).  

Ice ceiling up close ( with dive hole in the distance)

Looking up at the ice from below, it looks like a grey stormy sky-full of clouds. Varying shades of darkness representing the uneven nature of the ice, revealing the thinner parts or the heavily snow-covered patches. The ice we have been diving through at OB1 is approx 2m thick, but lets in a surprising amount of light when clear of snow. At a few sites, the ice was thin enough to allow the shadow of the Hag to be visible to the divers below, but more than sturdy enough to hold it's weight.

With all their tasks completed , or occasionally infuriatingly aborted, the diver slowly make their way back to the shotline at the supervisor's request, and leaving bottom start making their way up to a 3m safety stop. Here they hover for the next 5minutes, clearing their bodies of as much nitrogen build-up as possible, and watching the blue world around them (or their bubbles racing to the surface through the hole). Once on surface, they have to be assisted out of the water, since they very suddenly now have to carry all their weight again, and the tenders proceed to remove all their gear.   

Curious Weddell

Uninterested Weddell

Some days in the field we have been graced by the curious visit of a Weddell seal (or two), poking it's head up through the dive hole to snuffle about and peer at us before taking off under the ice. On occasions, they have simply stayed right next to the dive site the entire day, napping and ignoring our noisy presence.  

More often though we have been visited by the very curious Adélie penguins, arriving in hoards of up to 40penguins, taking what seems like a guided tour of our surface installations. They've gotten bolder and bolder, approaching us with caution at first and now even venturing up to touch some of our gear. 

penguin parades

After a day-full of this kind of experience, the Hag trip back to station provides a great time to reflect on just how incredibly lucky we are to be part of this, and wonder what wonderful meal is waiting for us in the mess when we get home.  

Ice-cliffs as seen from the boat

I feel truly awed at the fact that not only to I have the privilege of being down in this surreal part of the world, but I also get to be one of the very few people who get to see what magic the world under the ice contains. And so I apologize for the length of this particular post, but even here have not been able to convey as much of this wonder as I wish I could.  

And so, I leave you with one of my favorite photos yet. 

And some bonus seallyness for your day :)