Penguin extravaganza!!!!

We went to Gardner Island again this weekend to greet our lovely neighbours. They are busy with nesting and preparations for the little ones to arrive and there is never a dull moment in the colony. The snow is melting, the sea ice slowly decaying and the open water drawing ever nearer with a steady stream of waddling penguins heading to the ice edge. These darlings are truly accomplished mountaineers - despite of their short feet and stubby appearance they are incredibly agile on rocks and can advance up the hillside of polished rocks at great speeds if necessary. Their tail is a very efficient rudder in the water but doubles very well as a walking stick with the beak functioning as an ice axe for self arresting and getting up those extra tricky spots.

The station has been a quiet place this weekend with several field parties heading out to the various huts. The weather has been incredible and Davis the Riviera of the South lived up to its reputation yesterday with temperatures reaching +5 C with almost no wind at all. I have been taking regular sun photometer measurements which require a clear sky. The photometer measures direct solar irradiance at five different wavelengths: 380nm (UV), 500nm and 675nm (VIS), and 936nm and 1020nm (IR) and calculates the aerosol optical thickness (AOT). It also determines the water vapour column (how much water vapour in total a narrow beam of sunlight encounters as it traverses through the atmosphere to the surface) by comparing measured irradiances on the 936nm and 1020nm channels (936nm = absorption peak, 1020nm = off-absorption). It is a very smart little instrument not much bigger than a satellite phone assembly and can be used either handheld or mounted to a tripod.

I have also been learning some laser maintenance from Andrew and Tony. Before coming here I had never had a chance to look at the inner workings of a class 4 laser (let alone pull one apart!) and after an initial shock the device is starting to look a bit less overwhelming. We swapped one of the amplifiers which allowed me to see the actual cladding, Nd:YAG rod, flashlamp and the various other associated bits and pieces. I also learned the basics of how to do a standard optical check of the whole beam path (from the seeder all the way to the final beam output) as well as a standard power check on the oscillator itself. There is so much to learn but it is excellent to be able to do some hands on work as it helps to gain a good understanding of the data - it would feel rather uncomfortable to work on a dataset produced by an instrument whose workings I didn't have a faintest idea about.