Everywhere around here the landscapes are astounding. It is unique to have underwater landscapes where you can see far in the distance. Above you can see Rowan filming the seafloor near Rob and Amy doing some oxygen measurements. The distance is deceiving in many ways. They are strangely close to me but seem far away (and my dive buddies were Jacob and Steve who are just out of the frame to my left and right).
Even the surface of the ice is surreal. You can see my bubbles but the rest of the features are just how it looks.
But it really doesn’t stop at the ice surface. All of the views are as grand as one can get. Its inspiring to be surrounded by ice and stone on a scale that defies imagination.
The far side of the sound (where Michael’s post described the trip out to) is very different underwater. Sandy, non-volcanic rocks and lots of different types of life.
There are still sponges but many different kinds of animals that we don’t really see near McMurdo station. Especially scallops which cover the seafloor.
While we get Crinoids on both sides of the sound, there were two at the site that we were working at. I only saw one, but it was a pretty one. These are closely related to star fish, sea urchins, and sea cucumbers and swim by waiving all their arms in a rhythmic pattern. We didn’t see any swimming though.
And in addition to the life on the seafloor, the algae growing on the underside of the ice, truly made the place special.
We have been doing more and more dives trying to get in as much research as possible into the season. One of the really important parts of doing research anywhere is also looking around and seeing the environment. I have been fortunate enough to dive at the Jetty site since I started working here and so I also get to see how things have changed. While this site is the most dove on in the region, it is still full of amazing life and animals.
Here is a large hexactinellid sponge – or also known as a glass sponge. These are very large and are more frequent, or at least larger the deeper you go. This one is a really nice and healthy looking one that has a sea spider walking around on it.
However not all of them are looking great. This is the same species but is instead being actively grazed upon by some sponge-eating sea stars (Acodontaster).
As we go shallower we see very large sea squirts (tunicates -Cnimidocarpa in this instance) as well as soft corals.
Its by going back and back to the same sites that we get to see change. It is one of the amazing things about this place – the ability to watch a very slow to respond ecosystem change over time. What windows will this provide into our understanding of this amazing region in the future?
It has been a dark year under the ice. Heavy snow has made very little light shine through to the depths. However, the scenery is no less spectacular. Here is a short clip showing what a “normal” dive looks like for us.
One of the main research questions we have focuses on the research site known as Cinder Cones. This is an area where methane leaks from the seafloor and is harvested by microbes for energy. Over the last 10 years the obvious microbial communities have been slowly replaced by dense beds of sand anemones (Edwarsia). This is what it looks like this year – tons and tons of them everywhere.
There are also tons of the star fish that seem to have come into this region. More on that in a future post, but there appears to be an interesting relationship between the stars and what the seep is doing to the ecosystem.
You can still see the small areas of microbial mats being present but they are far more reduced than previous years. However our research is showing that there is still a lot of methane being released. In the image above you can see the small patches of white which are indicative of where methane is seeping from the seafloor.
This area has become a real interesting and yet perplexing place to research, but like all good research sites – it keeps surprising us with its novelty and unexpected patterns. This all lets us better understand how the greenhouse gas methane is kept out of the atmosphere, one microbe at a time.
One of our main research sites is called Cinder Cones. It is an area where methane is actively being released from the seafloor and we really want to know who eats it so it stays out of the atmosphere. Its microbes… but which ones!? But step one? Getting a dive site there.
This starts with heading out on the ice, using all of our trainings (both new and old) to make sure we stay safe. Today we were accompanied by Mitch, the person in charge of Sea Ice Safety, as well as a Cadre of people to get to the site and knock out a dive. This is a challenge in itself, but step one is getting to the site.
The sea ice is thick this year (2m/6ft or so at least) but there are still cracks and we need to make sure that they are both thick enough and wide enough for our vehicles (designed to cross cracks) to cross. Our Piston Bully (the red vehicle shown at the top) can cross cold ice that is >30cm thick and areas less thick than that as long as the gap is <91 cm. We are trained (and have an expert along to help) to make sure we are always on ice that is much better than this limit. The challenge is actually recognizing a crack sometimes and also, sometimes cracks can be larger than that. Above is a photo of the crack that turned a 5 hour day into an 8+ hour day. It is too wide and thin to cross, but also completely covered by snow. To measure thickness we have to dig it out and then drill down to see how thick it is. And we (and by we I mean mostly Michael and Jacob) something on the order of 25+ times.
We eventually found a crossing point that was nice and thick and narrow but it took us an additional 15 miles out of our way. And Piston Bully’s look cool and are great, but fast they are not. I expected to get to our dive site around 11am or so but we got there at 3:30 pm instead.
Most of this was spent digging and drilling. But the day was fine and the weather balmy (for Antarctica).
As an added advantage, I got to go to a part of the bay that I had never been before and as always, the views were just constantly beautiful and ever changing. Ice and rock, in constant battle and contrast.
In the end, we decided to postpone the dive until tomorrow. But we have a hut, a hole, and a safe route. Who could ask for anything more? Huge thanks to Mitch, Eric (the driller) and two people from the Carpenter Shop who spent the day with us to support our science.
It is wonderful to be back in Antarctica after a year away. New colleagues, faces, and a reintroduction to the amazing ice above water. After a slough of trainings we also began to dive again under the ice. The first trip under was the three of us that have dove here before. We still do the same briefing and checkout dive as everyone else, but are used to the immediate shock of the cold… followed by the shock of the amazing animals underwater.
Every year is amazingly different in a place where many of the animals live decades if not centuries. This year I was incredibly surprised to see soo much of this sponge (the upright bush looking thing) are one of our most frequented sites “The Jetty”, named after it being right next to the jetty where the water intake pipes for the station sit (those pipes bring in salt water for us to desalinate and drink, as well as pumping nice and cold, fresh seawater into the aquarium room). This sponge is one that grows quickly and then poof is all gone, but the bushes were dense this year!
The other difference is that there is a bunch of snow on the ice, making it very dark underneath. Last year it was pretty dark, this year it is DARK. A really interesting fact is that the ice thickness doesn’t really impact the amount of light, but it is all how much snow is on the top. I have dove with 18ft/6m of ice over my head and it is bright as an overcast day, and under 3 ft of ice with a bit of snow on it and it is the darkest night.
But the diversity that lives here remains to astound me with each foray under the frozen ocean surface. It is good to be back underwater and in the most amazing, if not warmest, place on the planet.
By this point, we have done many dives at the McMurdo Jetty dive site. It is close and provides a lot of great sampling opportunities. I have done whole research projects here. It is frequently known as the “Great Provider” for research, and it always seems to amaze. To day was no different.
We poked around a little deeper looking for microbial mats with no luck. Above you can see Rowan, Lila, and Rob heading back to the Jetty after our look around deeper with no luck.
Rob had remembered that there may be a mat around the far side so led the way.
CRIMINY! Look at it! A deep bubbly mat right next to where we have been looking for the whole trip down here. And look at all of those amazing critters around it. Bryozoans, hydroids, giant tunicates (sea squirts), and even some fish! Clearly this will fill out last week in Antarctica with some exciting science.
One of the challenges of it being light all the time now, is that colors are best at sunset. We got to enjoy a lot of amazing sunsets during winfly but that was a bit ago and now the sun never sets, it just goes behind a mountain for a quick snooze. Now that we are at all of our dive sites, we wanted some more imagery to help communicate the seasonality and different locations, so off we went late in the evening to capture some good light.
Justin, Rowan and I headed out after dinner to see if we could time clear skies with good light and we were not dissapointed.
Rowan has decided that her drysuit undergarments are the most comfortable thing ever and so now wears them whenever the cold is going to be there. So she can do things like sit on a frozen ocean taking photos and not care about the cold. You can also tell that she has gotten used to the cold of Antarctica, no hat, no gloves. It was super warm too… like -20C.
We went out to Turtle Rocks and were treated with a warm pastel glow on Mount Erebus. The light to the right of the image above was an amazing green/blue and the light hitting the many aspects of the glaciers coming down the mountain on the left made our trip worthwhile.
On the way back, the light got better and better. This shot was at midnight, the lowest the sun will get for months. I have been blown away by the panorama shots that Rowan has been getting so this was my attempt to capture images as amazing as what she captures on a daily basis.
As we head home, and the sun starts rising again we were met with one of the weird marages that appears here combined with a spectacular sunlight spectrum. Note that the land is stretched and the sky is on fire. Amazing evening on a frozen ocean to catch the light that both ends and begins the day – which co-occur here.
Diving in Antarctica is demanding. Really, diving anywhere can be pretty demanding. Throw in a few layers of complexity in the form of incredibly cold weather and a ceiling of ice above your head and you’ve got quite a situation on your hands. So what is required, in the most practical sense, to dive in Antarctica? Support vehicles, dive huts, robust equipment, drysuits, layers of insulation, air, lights, a hole to dive in and possibly most importantly a good attitude and a cool head. It’s amazing to watch the dive team execute the seamless dance of moving all the equipment into place, getting the work done underwater, pack up the whole show then clean and prep only to do it again tomorrow.
At the core of this effort is Rob Robbins, the USAP Dive Services Supervisor who has been on site here at McMurdo helping us in countless ways. The average dive duration under the ice here is 45 minutes (though I’ve seen some as long as an hour). The entire process from walking in the door at the dive locker to returning, cleaning gear and leaving the dive locker is about a 3 hour process at even the closest location.
Behind the scenes, Rob is inspecting gear, checking weather, doing repairs, filling tanks and keeping up probably the most tidy shop on the island. Aside from the physical aspects required to support diving here, Rob is patiently willing to discuss any and all aspects of the sometimes overwhelming mental preparation required to dive under the ice. Our team simply couldn’t perform the work down here without Rob’s tireless efforts.
