Questions from Gustavus School Oct 17, 2003
How is your dive equipment different from what you use in Glacier Bay?
In Glacier Bay, AK the water temperature is ~43°F on average during the summer months. Although this is fairly cold, it is above the freezing point of seawater. In the Antarctic, the water temperature is 28°F, which is just barely above the freezing point of seawater. Additionally, the air temperature is below freezing (on average 0°F not including wind chill). Therefore, in the Antarctic, our SCUBA gear (and our bodies) are much more susceptible to freezing, and there are a few things that we do differently than diving in Alaska.
1. To prevent a dangerous situation of your regulator freezing up (the piece of equipment on the SCUBA tank that delivers air at ambient pressure) we have two regulators on one tank; in Alaska we only use one regulator. You breathe off one regulator that doesn’t have gauges or inflator hoses attached to it, and that leaves you with a separate back-up regulator that does have your gauges (air pressure and depth) and your inflator hose. Therefore, if your regulator were to freeze, you could switch to the alternate regulator and your gauges and inflator would still work. At that point you would want to be heading for the surface in case your back-up regulator were to freeze.
2. We wear dry gloves in the Antarctic while we wear neoprene gloves in Alaska. We first put a thick fleecy glove on our hands. Then we fit rubber gloves over the fleece (just like the blue fishing gloves you may be familiar with) that have a latex cuff that is pulled over a ring on the cuff of your drysuit that seals them. Then you hands stay completely dry and relatively warm (if everything works properly).
3. Because of the very cold water, we wear three hoods instead of the two we wear in Alaska. The additional hood is called a gorilla mask that is made of thin neoprene and it covers your upper lip, chin, and cheeks (you end up looking like a bank robber). We also wear thicker socks, booties, and undergarments beneath our dry suit to try to stay warm.
What were your first thoughts when you entered the water during your first dive, what were your expectations for your first dive, and were they met?
My first thoughts were, wow- this is dark, cold, and scary. But then I turned my light on and I could see 80 feet to the bottom! In fact, the water was so clear that I could make out individual critters on the bottom and soon I forgot that the water was cold (or my lips went numb) and I was fixed on trying to understand all the strange creatures before my eyes. It was unlike anything I had seen before. The most similar environment I could relate it to be was that of the deep sea in Monterey, CA, that I had only seen in an aquarium exhibit.
My expectations were simply to have a safe first dive with all this new equipment, to get used to diving below ice which I thought was going to make me quite anxious, and to never lose sight of the hole that I dove through so that I could get out (there is generally one way in and one way out).
I did indeed have a safe dive and the hole was very easy to see. The thick sea ice (15 feet thick) with the few feet of snow on top of that lets little ambient light through to the seafloor. So when you look up at the hole from the bottom, it looks like the moon with rays of light penetrating to the seafloor. As far as the equipment goes, it will take a few dives to really get used to it, but all in all the first dive went better than I expected.
Craig Lewis says:
JP8 is jet fuel, but almost identical to diesel, kerosene and heating oil. Since we don't always know if we'll be using the fuel for a stove, a truck or a helicopter, we use the highest grade of fuel for almost everything. Since the helicopters are the pickiest about what they burn, the standard fuel is JP8.
What do people get sick from?
Jennifer Fisher says:
Unfortunately, when people are living close together in a communal situation germs spread fast. People often get sick from a germ that somebody brought from outside the continent (like the flu, sore throat, cough, etc.). Once one person arrives on the station sick, the germs are easily spread since we all eat in the same environment (dishing food out of the same food troughs) and often work very close together.
Paris: What kind of sea life do you encounter? What is the most interesting species you have seen?
Jonna Engel says:
The most common kind of sea life that we encounter are marine invertebrates which are animals without backbones. The most common invertebrates that are in Antarctica are sponges or Porifera. These are the simplest of the marine invertebrates with only two tissue layers and a very simple body plan. They are filter feeders, straining plankton out of the water column for nutrition. Sponges come in a variety of colors including cream, yellow, orange, and red.
One of the most beautiful animals that we see when we dive in McMurdo Sound is the athecate hydroid, Corymorpha parvula. Hydroids are members of the Phylum Cnidaria which includes sea anemones, corals, and jellies. They are permanently attached to the substrate as adults and we most often see then attached to rocks but sometimes they are attached to sponges and more rarely the big tunicate, Cnemidocarpa verrucosa. C. parvula has been observed in Antarctica from depths of 3 to 144 meters. It is a delicate and beautiful animal with a distinctive reddish-brown/brick-red color and about 30 aboral tentacles, each about 1 centimeter in length. C. parvula preys on bottom dwelling species, primarily diatoms, but also amphipods, copepods, nematodes, invertebrate eggs, sea urchin juveniles, and hydrozoans. Like many Cnidarians, C. parvula’s life cycle alternates between a polyp stage and a medusa stage. The conspicuous phase of C. parvula is the polyp stage: this is the sessile or permanently attached stage that we see when diving. The free-swimming medusae stage arises from the long tentacles, dedicated to reproduction, that surround the hydroids mouth. The medusae are quite small (apprx. 1cm) and they are pointed with a ring of tentacles that have beads of stinging cells.
How often does your communication system break down?
Stacy Kim says:
Very rarely does our communication system break down. For safety, it is very important to maintain communication between the main station at McMurdo and the groups in the field. If someone got hurt, one of our first actions would be to call for help from McMurdo, where there are medical supplies, skills, and facilities. So we are almost always in VHF radio contact with the department known as MacOps, who monitor our daily expeditions. When we are in the field camp, we check with them every morning as well, usually by radiophone. If the radiophone is not working, we can try VHF radio. Our handheld VHF radios are not very powerful, but there are repeaters on various mountaintops that can rebroadcast our signal. If we are not in line of sight to any of these, or if the repeaters are down, we can always fall back on the HF radio. This powerful, bulky system uses a large wire antennae that must be tuned to the proper frequency and aimed at the receiver. It is an unfamiliar system to most of us, so we are trained to use it in Happy Campers school.
For communication with the rest of the world, we have satellite phone links. The bandwidth is fairly limited on these, so it is hard to get an outside line and internet connections are pretty slow. However, considering that we are at the bottom of the earth, it is amazing that we have phone and internet connectivity at all. I want to take this opportunity to point out that Jim has worked quite hard to post our daily updates over these "clunky" connections, especially from New Harbor where it all had to go over a single phone line!
What do you miss most?
Stacy Kim says:
I miss my two dogs most intensely! We all miss our families and friends, but at least we can email and phone them. Other things that I notice a distinct lack of down here are green growing things (including vegetables and fruit to eat), waves and moving water, night skies and stars, and good scents…there are a lot of stinky feet but no flowers!
What are you studying in the water?
Stacy Kim says:
We are studying human impacts on the seafloor communities, and how the marine animals recover from human-created disturbances. McMurdo Station has just built a sewage treatment plant, and one of the things we are looking at is how the ecosystem is recovering now that the sewage is treated. We are also studying the different impacts of burial, and organic enrichment, two natural processes that occur on altered scales near the outfall. The third section of our research is looking at long term changes in the seafloor community, and how things recruit, grow and change over decades.
Are you able to sleep through the night on the ice or do you wake up many times?
Jim Oakden says:
It can be a bit disorienting here, since there really isn't a "night" as such. The sun won't set again until March. I generally don't have a problem sleeping any time (barring roomates and fire drills), and here is no exception. However, having 24 hours of daylight makes it very easy to just keep going. Doing dives at midnight and staying up working till 3 can happen here. Fortunately, the meal times in the galley offer a built-in circadian rhythm, since we REALLY don't like missing meals. It is important to try to keep to a schedule to prevent exhaustion from setting in. If that happens, one can accidentally fall asleep at the oddest times, like right in the middle of...........zzzzzzz :)