Microbial Mud

Today started in the not so usual fashion. Rory woke up raring to go and headed to the gym. En route he pulled a muscle in his back and that pretty much ended his day at around 7am. We were going to go to a new dive spot where I heard that there was a pretty cool sediment feature to check out. The place is pretty close to station and called cinder cones.

Immediately upon entering the water I was blown away by the ice shapes. There was an incredible amount of ice algae providing a strange mix of colors and the sea ice cracks were spectacular.

The bottom of the sea ice with strange hues of green (ice algae) and blues (ice).

The real find was the wall of bacterial mat. The bacteria here uses sulfide (H2S) and mixes it with Oxygen to get energy. Its a chemosynthetic process so does not use the power of the sun.

The white in front is bacteria not ice. Its a thick mat of it and is an indication of interesting chemistry in the sediment below.

I now get to sort through the core to see what lives in it. I have high hopes as communities like this have been a focus of my research in the deep sea and I am excited to see what the cold microbial mats contain at a shallow 40ft.

A different day

The snowfields of the permanent ice shelf meet the cravasse filled slopes of Erebus.

For the last two days, Rory and I have been staring through microscopes.  I’ve been enamored with the microscopic world while he has been counting little glowing dots in the dark.  But I think we both have been thinking about our hike that we took last Sunday.

The walk to Castle Rock is along a ridgeline right above town. The entire route is flagged making it safe to travel and it is constantly monitored for shifts in the ice that would make it unsafe.  There is even a safety shelter that you can see as a little red dot.  As the weather here can go from this (calm, no wind, warm at -11C) to hurricane force winds and wind chills down to -70C in less than an hour.  Anytime you are more than an hour from the station you must have a way to shelter yourself and survive such a storm.

This is the goal.  Castle Rock.  It is only a 3 mile hike but that takes a bit longer than it would elsewhere since we have to be dressed for the occasion.

Later in the season there is a route to the top of the rock but right now we can just hike up to the saddle before the climb. Here is Rory doing just that. The real challenge that day was not getting too warm! With the sun out and no wind I didn’t even don my Big Red (i.e. red coat) and instead sweated away in a fleece. Rory wore his Big Red as a cape.

This is the view north. You can see an ice tongue off as a different shade of light about half way to the islands. That ice tongue causes many cracks in the sea ice that we have to monitor as we travel around. The islands are Tent Island, Inaccessible Island, and then Big and Little Razorback islands before the north end which is Cape Evans and one of the sites we occasionally dive.

The Expanse Looking South. The next stop here is the south pole. Flat. White. Snow and Ice for miles. This is the view the initial explorers saw as they attempted to tackle the continent at the turn of the last century. It is still an awe inspiring view and so close to where we live and work now.

Ice thickness and temperature

Julia McFarland’s 7th Grade science class from Egan Junior High School from Los Altos, CA asks:

How thick is the ice and when you jump in how cold is it?

The ice is currently right around 1.4 meters thick or 4- 5 ft.  The water is -1.8C or 28 F.  This is two C below freezing and as cold as seawater gets before it freezes.  As soon as we jump in all of our skin that is exposed, which is only our lips, goes numb immediately so it really is not that cold after the initial shock.

You can see here that we are pretty much entirely covered up. The little sliver around our lips is all that is exposed.

 

The ice is slowly thickening during this time of year and at one of our dive spots it has gotten to around 12 feet.  A lot of that ice is unconsolidated “brash” ice which means if we touch it it moves more like a slushy or more like snow than ice.  Starting in mid to late November the weather warms where the sea ice is no longer thickening and it will eventually break out.  This normally happens  every year but every once in a while the sea ice will stay here for a few years creating very thick ice, in the past decade we have seen 12-18 ft of ice where we have 3 ft this year.

 

This is what the bottom of 12ft of ice with 6ft of snow on top looks like.the jagged ice around the side is the brash ice.

Mystery Peaks and Walls

As the season progresses a few things happen. The visibility in the water gets worse, the station gets crowded, and other animals start showing up. While this normally just means seals that have come up to pup, there are also weird wanders.

This Weddell Seal was quite happy to make use of our dive hole to come out and relax in the sunshine. Because he was there we ended up diving outside of the hut (meaning we were exposed to -25C with windchill while getting ready to jump in the oca) so the seal would keep access to the ocean. But we couldn’t really argue with a face that that.

While we were underwater these two Emperor pengiuns happened by. We had seen them earlier as we were driving to the site. They came right over to me on their bellies scooting along. One of the nice things about working in an area where humans don’t harvest the wildlife is that the animals are curious about us and so as long as we stand still they come say hi.

Why walk when you can scoot?

I think this is the secret to moving on the ice. Stay low and you never fall far and won’t trip on a ridge of ice.

We went out that day to dive on a new site. It was very interesting in that it was the top of a sea mount at the end of a glacier tongue coming off an active volcano. The entire top was covered by a single species of sponge, a few anemone’s and bunch of nudibranchs that were eating the sponge.

There was a great field of nothing but this on top of the seamount. It was just discovered in the last few years and we were the first divers to see it. Very cool. We were there en route to another dive location with the group that was studying it. Since we were sharing resources we decided to dive too.

The real purpose of the trip for us was to get some samples of the bacterial rivers coming from underneath the glacier. I put in a photo of it before but the more we talked about it the more we thought it could be something very novel so we went back. Rory and I spent the better part of a week devising multiple ways to get through the ice and collect samples of it. Amazingly the first approach worked. We took a sample from the vein of the glacier using the same technique as if it was our arm 0 using a really big syringe with a really big needle. I was most proud of not stabbing myself in the hand with the needle after taking the sample. While normally we just discard needles rather than recap them – that is not an option when you are at 90ft with nothing but a mesh bag and are floating around in a big balloon (i.e. drysuit) that doesn’t like sharp things.

This syringe worked surprisingly well to get the sample from beneath the ~3cm of ice. You can see the wall of ice that was ~ 90ft to the seasurface and another 90ft above that towering over our head. The syringe saved us from using ice screws, a hammer, a hole making bit from a drill, and a bunch of other things that Rory had brought just in case.

 

Here’s another view of the wall for perspective.

Employee of the month

We recently completed another crucial time point (week 4) in our big 6 week experiment. WOO WHOOO!!! The end is near. All the live animals have been sorted and the rest of the samples preserved for later analysis. A huge plus for us is that none of our super critical science equipment that we transported down here has broken yet. Although when we first got down here and we were ramping up for the start of the big experiment we were running into problems right and left. In an attempt to remedy this situation we started a little incentive based encouragement aimed at our science equipment. We awarded “employee of the month” to our extruder, the only piece of equipment that was not giving us any issues.

Employee of the month

The extruder is just a little device that allows us to sample and section the sediment into different layers from the surface on down. We made a little photo employee of the month sign and hung it next to the window in our lab and wouldn’t you know it all the equipment has been working beautifully ever since. Well another month has come and gone and it is time to select the next”employee of the month” less Murphy’s Law goes into full effect. This gives me an excellent opportunity to introduce a few of the other instruments we use to complete our science down here.

     The first two clear front runners are the oxygen sensor and meter combo and the dissecting microscope with the digital Canon camera with the microscope eye piece attachment that allows Andrew to get all the super detailed close up shots and videos of the animals in the sediment.

Science toys. Clockwise from top: digital canon camera with microscope eyepiece adapter, oxygen sensor connected to oxygen meter in the front right foreground and dissecting microscope with ipod headphones hanging from the oculars (music helps pass the time during long hours on the microscope).

The underdog in the science equipment race for employee of the month is our under water sediment core transport rack, which is really just a milk crate with a bunch divider ropes strung through it and carabiner for attaching it to the dive line. Always carefull not to offend we never call it a milk crate in front of others, and it also really ups our science cred around the dive tenders to give our home made items fancy names. The milk crate also doubles as a support rack in our respirometry table. The respirometry table is an aquarium tank with 1.8°C seawater flowing through it to keep the animals that live on and in the sediment at the same environmental conditions as where we found them. I have a soft spot for underdogs so my money is on the multitasking milkcrate.

Underwater sediment core transporter (A.K.A. milk crate with rope strung through it).

 

Happy Camper

On Monday and Tuesday we had Happy Camper, which means spending a night outdoors getting a genuine taste of the Antarctica field experience. The goal of the course is to provide Antarctic survival training on what to do in case you get stranded out in the field.

The group at Field Safety Training Program (FSTP) take a handful of individuals from each station. Sometimes the weather is nice and sometimes it is really nasty. Lucky for us it was gorgeous out… gorgeous for this time of year in Antarctica (light winds and 3°F).

 

We started in a classroom and then packed into a delta vehicle shuttle and sped out at max speed (15mph). We camped on a glacier near the base of Antarctica’s second largest active volcano, Mt. Erebus! There were spectacular views all around.

View from camp of Mt. Erebus smoking in distance

We dug snow shelters, made ice walls to block the wind, and set up tents. We all split up into tasks and our volunteer chef prepared “boiled water” from scratch, using only glacier snow and a whisper light stove.

dugout “kitchen” with ice wall

Just before our FSTP instructor Cory left us for the night, he gave us the dehydrated meals we were to add boiling water and have for dinner. When I asked which ones were good, he smiled and said “They’re all good as long as you add enough of the world’s best spice: hunger.”

Right he was. Your body burns an incredible amount of calories trying to stay warm in these extreme conditions. When trying to stay warm you can eat, hydrate, put on layers, or move around to increase circulation. I did all of them and paid for it in the middle of night when I had to leave the warmth and comfort of my sleeping bag to get up and pee. Next time I’ll just wear everything I own, drink a modest amount, eat like a horse, and shovel snow.

Ice wall protecting tents from wind

Everyone was up and moving breaking down camp at 5:30 am… well, everyone except me and one other non-morning person. I sort of shuffled around in a circle nursing my instant coffee until my eyes fully opened. We all had more boiled water with instant oatmeal and instant coffee, and then awaited pick up.

breaking down camp and awaiting pick up

The rest of the day was spent learning how to use very high frequency (VHF) radios and repeater towers when there is no line of sight. We also learned about high frequency (HF) radios for extreme field sites. Then we tested all the training we learned in a pretend scenario wherein we were told we had 15 minutes before a storm hit and we needed to set up camp and radio for help using just one survival bag and HF radio.

A day of dives

We arrived back from our survival training having successfully survived. Today we went north to help out a fellow science group. Since there are only three approved divers on station at the moment and we always (both by requirement and common sense) dive with a buddy, we were asked to join Steve as he did some collections and checked on an instrument. Not all groups that need access to the ocean bring divers, many rely on the station divers. The first dive was at a spot that has a glacier running right down into the water.  Since there is lots of snow on the ice it is pitch black underwater with only a few areas where light peaks through cracks.

This is the view looking along the ice wall. the sea ice is above and other than that it is straight up and down and extends off into the distance.

It is truly an amazing site with yellow bacterial rivers frozen but appearing to stream from underneath its edge.

It was quite dark as there was lots of snow on the ice. Here is Steve, the Dive Safety Officer, swimming towards us with his video light on.

As always. there is amazing clarity which allowed us to see ice forming on the large boulders dropped from the glacier’s persistent movement. Some of the boulders had been there for a long time with large animals growing on them and other boulders seemed to have just fallen off and were completely devoid of animals.

The dive ended with a seal deciding to take some breaths at our dive hole.  After we got out it came up and visited with us, as in kept on looking at us as we packed up our kit.

Here is the seal looking down at us. He was quite happy that we made a hole for him.

The second dive was at a spot that has lots of light and hard hard substrate – no coring possible. But it was neat to see a new site. The ice was in full bloom with lots of algae growing all over except in the hundreds of little brincicles forming on the bottom of the sea ice. There were urchins GALORE.

This is what the seafloor looked like at Cape Evans proper. This species of urchin is Sterechinus neumayeri.


If you look closely here you can see that the urchin is spawning.


Here is the surface of the ice. You can see many many little brine-cicles that form when the sea water freezes. Seawater forms freshwater ice and rejects super salty water out of its base. Where this happens these little seawater icicles form. The color of the ice is from ice algae that is growing underneath it. We have not seen much ice algae this year because most of our sites are so dark compared to this one.

It was so bright that you can see the shadow of the dive hut and our vehicle on the surface of the ice from below. You can also see Rory at his safety stop on his way up.

Ask Scientist: How cold is the water?

Dear Polar Scientists,

I like to watch Frozen Planet on tv because it’s interesting because there’s lots of strange creatures that live in the arctic. My favorite is the Woolly Bear caterpillar.

 

My question to you is; What is the temperature of the water where you are and how do you protect yourself from the cold water?

 

Stay warm!

Adelina Brown | Second Grade | Beaubien Elementary | Chicago, IL

I like the Frozen Planet too. The Icy Finger of Death Brinicle time lapse video is my favorite, and we saw the place they filmed that shot two days ago.  The water where we are diving is -1.8°C or 28°F. That’s below freezing for fresh water and the approximate freezing temperature for sea (or salt) water. However, that is still much “warmer” than the air temperature has ever reached since we’ve been here. In fact, when we drill a fresh dive hole we see steam rising off the sea water (like a hot tub) which gives a false impression of warmth.

We try our best to protect ourselves from the cold water. We have special dry suits and dry gloves for scuba diving to make sure we are in minimal contact with the water.  Our mouths are the only exposed part of our body and they go numb almost immediately. I had a glove leak once during a dive, and although I was able to finish the science goals for the dive, it was quite painful.

This is what we wear underneath our drysuits. We start with expedition weight long underwear and then add between one and two pairs of socks. I use a thin fleece pair with a thick wool pair on top. We then get in that big fleece jump suit and add another sock layer. Our feet and hands get the coldest of all.

The real secret to cold cold water diving is dry gloves. These gloves attach to our suit so our hands stay dry throughout the dive. Underneath I put a very thin fleece liner and that is it. Even with all of this, we always end a dive with cold hands – there is just no way around it since we can’t put our hands in our pockets to warm them up like someone can on the surface.


The final addition to our setup are three hoods. This is the inner one, called a gorilla mask, and the two holes are for the mask and regulator. We then put a latex hood that is attached to the suit over the top of this and then a normal cold water diving (neoprene) hood on the outside. On a good dive our hair doesn’t even get wet, however they are not all like that. The hoods are very uncomfortable on the surface but underwater we don’t even notice they are there.

Ask A Scientist: How does your equipment handle the cold?

My question is what’s the extreme ratings for the equipment you use, and since it would seem that some would be life dependent are you required to bring redundant equipment for the expeditions you go on?

Your Concerned Uncle Dave | Connor-Winfield, Aurora, Illinois

 

The tanks, regulators and dive computers are all provided for us down here. These are the most important pieces of equipment we use, because if your tank or tank regulators fail you won’t have access to air.

We have two regulators on every tank.  In case one fails, we have a backup on hand and a buddy with another extra regulator to follow us back to the surface. That is just one example of the redundant equipment we use to stay safe.

Luckily, these items are maintained by the dive safety supervisors here at McMurdo. It is amazing how well this equipment holds up to these extreme conditions. Just look at all the ice covering our regulators after a dive.