Day 9 in Antarctica

December 5, 2013
We had an almost wind-free night, which made for quiet sleeping.  Our tents were flapping.

Today was Tyler's first dive and Ian's second.  Tyler mostly looked around and got used to the new dive gear.  Ian deployed an instrument called PAM (Pulse Amplitude Modulated spectrometer) that measures chlorophyll abundance and photosynthetic potential.  We left PAM in the lake measuring two spots for most of the month we were at Lake Vanda.


Ian and I drilling the first flight of a hole in the ice with Tyler watching.  Once we go down a flight. we stop drilling, disconnect the Jiffy drill at the top, add a flight, and do it all again, and again, and again.  We get to the lake water in the 4th flight.

After lunch, we drilled more holes in the ice and took more video.  Tyler's new video system is working very well.  When we've tried it before, we've had trouble getting the camera to spin properly.  However, this time, we have a SeaView camera that lets us see about how far the system is above the lake floor as well as how fast it is spinning.  We take video data with GoPro cameras in underwater housings.
Tyler and his cameras in the science tent.  The grey plastic cylinder is the SeaView camera.  The GoPro is on the end of the long PVC pipe looking inward so we get images of all sides of some of the pinnacles.  There are two dive lasers attached above the SeaView camera.  When they are on, they provide two red spots that are 3 cm apart no matter how far they are from the lake bottom.  The ropes keep the GoPro arm pointing downward when we lower it into or pull it out of the hole in the ice and the arm out after it has cleared the bottom of the hole.

The floor of the lake is covered with pinnacles to depths of about 50 m.

Screen shot of the GoPro camera view with the laser spots, the SeaView camera and a bolt at the end of a string with a straw on it to provide a down-indicator.

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