21 October 2004

Bob here again,

 

It’s my first day to write about diving and as this is my first year diving in Antarctica you may well expect some strong impressions. After my first dive down here was cut short by a regulator free flow and my mask being badly fogged I have taken a much more prepared attitude towards the dives. Our day today started with the same 6:30am trudge to the galley for some sustenance. This meal is important, as it will often have to take us through till dinner with only a little snacking in between.

We got about an hour of sorting things out in the lab before our volunteer dive tenders from the community showed up. (Thanks everyone for your help). They got a short lesson on how to use the oxygen and some more emergency instructions on the use of the radios. In our dive locker as we fold our drysuits and pack our hoods and gloves. Then we form a chain and start transferring gear bags, tanks, specimen coolers, cameras, and eventually ourselves in to the vehicles. I figure roughly it takes about 1000 lbs of gear to put 6 divers in the water for one dive. This gear will be transferred 4 times in and out of the trucks. The drive to the dive site is time for some of us to get some sleep. I don’t count this as extra sleep; it’s just part of our daily schedule.

 
Today's dive plan had me getting in the water with Stacy as my partner. She would be taking cores. This activity requires a lot of skill. You must swim without kicking up the bottom to the core site then hover with perfect neutral buoyancy. Then using a short section of plexiglass tube you grind it into the mud. Once you’ve got it deep enough you slide a plastic cap over the top and start fanning the sediment away from the side of the tube. With another plastic cap in your hand you slide it down the side of the tube and lift ever so slightly so the lid will slip over the bottom. All this is done with dry gloves on that are about equivalent to space suit gloves. It might sound easy but it takes dozens of practice times before you can achieve a 25% success rate. For today nothing less then 100% percent will do. The cores being taken are experiments that have been on the sea floor for 2 years.  My job is to swim over to Stacy and hand her lids. Then she hands me the core. I swim it back to place the core in the bucket and return with more lids. Or at least that’s the plan.  

One of the core tubes

   Getting ready to dive is already becoming second nature. Two layers of pile underwear, neoprene socks, and pile booties. My big red drysuit barely slides over this. But I am getting better at wriggling in. Getting my head through the neck seal also used to be much more difficult. As it constricts my neck, hopefully forming a waterproof seal, I still sometimes get that feeling that I can’t breathe, but this goes away with a few quick deep breaths. I just keep telling myself I will be in the water soon and it all feels great when that first wave of freezing water hits you. 

Ice forms on the primary regulator first stage as we breath air through it.

After the “space suit” zipper seals me in I sit on the edge of the hole and put on a harness with almost 40 pounds of lead in it. This weight belt allows me and my very buoyant fleece underwear to sink. The tank comes next. It has a Y stem on it with two ports, each with its own valve. One valve is rigged with a secondary regulator, pressure-depth gauge, and an inflator hose that allows me to put air from my tank into my suit; this air gives me buoyancy control and  helps keep me warm. The second valve simply has one regulator on it and it is our primary. If it gets some ice forming within it it will likely free flow giving us a powerful blast of uncontrolled air flow, requiring that we switch to the secondary regulator. Having 2 valves on the tank permits us to turn off the primary. If it were allowed to continue to flow it would empty the tank very quickly. 

The button in the middle of my chest is the suit air inflator

Donning the fins is simple. Then comes the hoods. The first hood is a gorilla hood. It has a small opening for my mask and an even smaller opening for my regulator. It fits snugly and doesn’t cause me any claustrophobia any more (the first few dives with this hood back in California was the most uncomfortable claustrophobia I have ever felt). Next is the latex hood built into my dry suit. And if it does its job it keeps my head dry. Last over my head is a thick neoprene hood that performs the lions share of the insulating job.

After taking a few deep breaths to relax myself I place my mask over one of my two remaining breathing orifices. I still sometimes experience a small anxiety with having only my now mostly occluded mouth left to breathe from. But just relaxing and thinking of how good it will be to get in the water soon brings me back the preparations with an appropriate attitude.

At this point if my mask isn’t fogged it’s time to finish the encapsulating process by adding the dry gloves. 

First is a thick fleece glove then a thin strong blue waterproof shell glove over that. Stretching the rubber glove seals over the rings in our suits is a challenge. 

After doing a visual check for glove leaks it’s time to gather my gauges and check my primary regulator  and put a burst of air in my suit. Then in one smooth half spinning motion I twist and aim my tank for the center of the hole

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The first sensation is the sting of the 28 degree Fahrenheit water on my lips. This lasts about 2 seconds then they are numb. My next chore is to open the air dump valve on my suit and start sinking in a blue sea of bubbles. The regulator seems to be breathing normally so I continue down the 15 foot long tube of ice, clearing my ears and now adding air back into my suit as the water pressure squeezes me. All at once my world changes from a small tight safe tube to a wide open free space. My claustrophobia switches to acrophobia. I can see the bottom 70 feet away and it is dotted with thousands of sea stars and hundreds of other creatures. The visibility is some ware between 500 and a 1000 feet. The sensation of being on the edge of a building exposed to a long fall is there. My descent rate picks up as the squeeze continues and I counter with more air in my suit. I assume the sky divers position with my hands near my ears and my knees bent. I look around in amazement as the critters grow larger and my dive computer chirps announcing the 60 foot level. A big blast on the suit inflator stops my descent as well as any air brakes should.
I check the depth and confirm that my computer is clicking down the maximum time I have on the bottom. Stacy has already started digging lids out of the goody bags. I follow her to the first core site with a few extra lids hovering over her as she works. Moments later with the smallest cloud of sediment  I have ever seen, she hands me a core. I swap her for the lids I have, then swim the core back to the bucket. Time flies as the bucket fills with cores and my air diminishes. A few times I get a little sideways and a bubble of air in my suit twists me on to my side or nearly upside down. I respond by allowing myself to drift up and away from the fragile bottom, then squirming around to right myself, being extra careful not to kick up any of the bottom. My air is getting low so I ascend to around 40ft where my air consumption will slow down. Now I can only watch Stacy work and be there for her if she gets into trouble. Before long the last core is in the bucket and Stacy is floating slowly up to me. The dive computer is recommending a 3 minute safety stop at 20 feet so we comply and fill the time doing funny dances to make each other laugh but mostly to stay warm. After ascending back up the ice hole I release one of the shoulder straps and the waist strap holding my tank on.  A long burst of air from the tank into my suit is the last service it provides for me. I detach the inflator hose and the dive tenders lift the tank and regs. out of the water. Next I slide one of the weight harness shoulder straps off and lift the other to the tenders to be removed from the hole also. The only encumbrance left is my fins. I pop the buckles on the straps and the eager tenders yank them off my feet. I float in the hole for a moment to catch my breath before climbing the ladder.

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