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.

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