Today was like Christmas and my birthday all wrapped up in one - the BIG day finally arrived. I went out on the Antarctic sea ice!
When I went to bed last night, the Oden was entering thicker sea ice, with bigger ice floes and less water showing between the floes. We were looking for a floe much larger than the Oden, with ice 1-2 meters thick, to tie the ship to so the different teams could safely collect their snow, ice, and water samples and our team could map and measure the sea ice thickness. I knew I needed to try to get a good night's sleep, but it is so hard to go to sleep down here. The unofficial term for this sleeplessness is "Big Eye." There is no darkness to tell your body it's time to sleep, and everywhere you look outside there's something new and amazing to see. My brain kept telling me "Don't go to bed yet - you might miss a whale about to surface near the boat, or that photo opportunity when the Antarctic Petrel lands on the ship, or... " I was glad I turned in when I did, because as I lowered the black-out blind in my cabin window, what do you think I saw outside on the ice? There were two Adelie penguins on an ice floe about 40 yards away, just watching the ship go by!
So early this morning, the Oden's helicopter pilot invited sea ice team member Brent out for a helicopter flight to look for larger ice floes and seals for the seal research team. Even though my cabin is directly under the helicopter pad, the ship is so well constructed that all I heard in my room was a little "wind." I didn't know it was the helicopter until someone told me it had been out on a flight.
The Oden carries a helicopter that , so far, has been used for ice surveillence and for the seal team to travel out to find seals.
Although several seals were spotted from the helicopter, no floes of appropriate size were seen. So it was decided that the seal team would fly out on their mission to find seals, land on the ice floes, capture the seal with a net, take measurements and tissue samples, release the seal, and repeat this procedure as many times as possible all day! So as the seal team left with Sven, the helicopter pilot, the rest of us waited with fingers crossed that we would be able to find an ice floe to begin our work. The head scientists and the captain decided to tie off to a smaller floe and try to do some of the research activities. So we watched from the bridge as the ship WAS maneuvered next to a floe which was about 250 meters long and 350 meters wide (Imagine an area about the size of 3 football fields.)
First, two crew members were lifted and then lowered off the ship onto the ice using a "cage" that was moved by the giant crane on the back deck.
Due to the small size of the ice floe and the weak edge, a 'birdcage' was used to get from the Oden down to the ice, instead of using a traditional gangway.
They assessed the ice thickness by poking a stick down into the ice, then they used a huge motorized auger to drill 3 holes into the ice. They inserted large metal pipes, about 1.5 meters long and at least 15 centimeters in diameter, into the holes, then tied the ship's docklines to them. Once the ship was secured, it was determined that only 4 people at a time would be allowed out on the floe and we would be the third group. We kept ourselves busy preparing our equipment , watching the group on the ice, and observing two crabeater seals dozing on a nearby ice floe.
The other science groups were working to collect ice cores (tube shaped pieces cut from the ice), snow samples, and sea water samples to analyze for different chemical and biological factors. I'll describe the other science projects in upcoming journals. The crew also deployed a CTD (a large water sampling device that collects water at different depths) from the bow of the Oden. It was lowered to 1500 meters below the ship, which meant the water beneath the Oden (and beneath our ice floe) was over 4500 feet deep!
The science teams collect ice core sample, sea water samples, and snow samples to analyze later in the ship's labs or back in the United States or Sweden.
The CTD id used to collect water samples. The bottles can be programmed to close at different depths which allows scientists to have a variety of samples to test.
Finally it was our team's turn. We donned our blue and gold "floating coveralls" (they have built in floatation devices), our snow boots, picked up our walkie-talkies, and hard-hats, and headed to the back deck for the ride in the "bird cage." Under my coveralls, I wore jeans, two thin, long sleeve shirts, wool socks, a fleece hat, and wool gloves under leather work gloves. The temperature was just below freezing, about -.5 C, and I was quite comfortable the entire time we were outside. The ride in the cage was a blast! You climb up a short ladder into the basket, trying to maneuver in your big snow boots, then just stand there and enjoy the ride. It was quite smooth and only took a few minutes. I was so excited that being afraid or nervous never crossed my mind.
Anne Marie Wotkyns and Blake Weissling ride in the basket from the Oden down to the ice floe.
Once on the ice we walked out about 30 yards to the "snow pits." the areas the other two teams had cleared of snow and taken their samples from. The snow was about 15 cm deep, and soft enough that our feet sunk down to the ice below in most areas. I was really surprised that there was a layer of "slush" - a slurry of ice and water a few cm deep - under the snow, but on top of the solid ice. I thought the snow would be sitting on ice that was smooth like an ice cube, but Blake explained that often the snow presses the ice down low enough that some seawater "floods" it. If the weather gets cold, then the "slush" can refreeze, adding a layer to the sea ice. Luckily, our boots were waterproof and our feet stayed dry. We found a flat area and set up our main project - calibrating our equipment. David and Brent set up a ladder with a wood "boom" from which Blake hung the EM device. The EM uses electromagnetic induction (sending and receiving magnetic waves) to measure the thickness of the sea ice. Blake needed to raise it to different levels above the ice and record its readings, then take physical measurements of the same ice and calibrate the device to the Antarctic ice. Then it would be ready for us to use for the rest of the trip.
Brent Stewart and Blake Weissling taking measurements to calibrate the EM Profiler device.
Blake set and read the hand-held controller, Brent measured the EM's height from the ice, David steadied the ladder and held the boom, and I recorded the readings and measurements in a small notebook. We were a great team! I also volunteered to walk back to the ship twice for additional supplies we left there. I enjoyed walking around and getting some exercise that was more than just climbing the flights of stairs on the Oden.
Anne Marie Wotkyns records data for sea ice measurements on an ice floe in the Antarctic.
After we finished with the EM, David used a hand auger to drill holes through the snow and ice down to the sea water. Then Blake used a brass weight attached to a measuring tape to measure the ice thickness. This device was very clever. It was shaped like a T with a loose screw attachment at the top of the T. It would fold straight and thin enough to fit down a skinny hole in the ice. Then when the measuring tape was gently pulled, the T would open up and catch at the ice's bottom edge and you could then record the thickness. Then another tug would release the catch and the T would collapse so you could pull it back up to the surface. We recorded the actual ice thickness in 7 holes in the same area we tested the EM over. Blake would use this information to calibrate the EM device. The ice was about 70 cm thick in all the holes we measured, an the snow ans "slush" another 15-20 cm on top of the ice.
Blake Weissling and the sea ice team measure sea ice thickness on an ice floe in the Antarctic.
After we finished, we loaded the supplies back on two sleds and walked back to the Oden. The officer on the bridge informed us that the helicopter was taking off for a second flight and the crane could not be used until the helicopter left, so we had some time to relax on the ice. We walked back to our work area and sat down, watching two Adelie penguins on the far edge of the floe. They seemed to be watching us too! They seemed curious and slowly walked a little closer when a large Southern Antarctic Petrel landed near the penguins. About a hundred meters from us, an avian face-off was brewing. The penguins and the large petrel faced off, flapped their wings, and postured a bit as we wondered out loud if petrels ate penguins?
Two Adelie penguins and a Southern Antarctic Petrel face of on an ice floe.
But, no way! Those Adelies held their ground until the petrel backed off and instead started heading toward us. Suddenly he started running right at us, wings spread, as Brent calmly commented that petrels were "really nasty birds." We breathed a sign of relief when he stopped about 20 meters away. He must have realized we were blocking his runway, so he turned and chose another path, running awkwardly across the floe until he was able to take off and fly away. The helicopter took off and we returned to the ship. We spent about 2 1/2 hours on the ice, completed our planned work, and had an AWESOME time doing it. Today is a day I will never forget!
Anne Marie Wotkyns in front of the Icebreaker Oden after completing sea ice work at a science station.
Lesson Learned - Not really a lesson today - just an observation- I have experienced something magical and life-changing today!