Aims:

There has been considerable speculation on the effects of the enhanced UV resulting from the ozone hole during the Antarctic spring. It has been suggested that the sea ice algae which grow rapidly during the spring would be particulary vulnerable to this radiation. The algae grow on the bottom surface of the sea ice. The transmission of ultraviolet and visible light through the sea ice using an artificial light source has been the study of K132-Buckley/Trodahl during the last three years, who have shown that not more than a few percent of incident ultraviolet radiation passes through the ice, being scattered by brine inclusions, and absorbed by the sea ice algae at the bottom of the ice.

Our programme has two parts. The first is to characterise the amount of UV and visible radiation falling onto the sea ice - the spectrum, the intensity, where it comes from in the sky, and the polarisation of the radiation. The second is to study the effects of enhanced UV radiation on sea ice algae under radiation levels both visible and ultraviolet which are typical of those encountered insitu.

Cargo:

The scientific equipment was shipped in 10 boxes. One box went astray on the way down and this caused some anguish. On return the procedure for shipping to Wellington seemed uncertain.

Personnel:

Professor D. Beaglehole, Grant Carter Department of Physics, Victoria University of Wellington Dr. Ken Ryan, Ross Exley DSIR/Physical Sciences, Lower Hutt

Preparations for the field:

All personel were very helpful.

Field Transport:

We had continuous use of ALP1 toboggan. Transport to Tent Island was by way of the Haglung, return by Toyota. All vehicles worked well.

Event Diary:

The study of the Antarctic skies in general required clear skys, although some overcast days were useful in calibrating the instruments. 4 days at Tent Island were unsuitable, but these were followed by 2 perfect days and allowed the completion of the measurements. A larger proportion of clear days were had at Scott Base. Algal studies were based at Scott Base with daily excursions to the sea ice beneath Arrival Heights to collect samples. Towards the end of our event several trips were made by toboggan to collect algae from the Tent Island camp site. Good weather during most of our stay meant that samples could be collected whenever they were needed.

Scott Base Laboratory Facilities:

The Geoscience Laboratory provided an excellent environment for study of data and repair of equipment (along with the mechanical workshop facilities). In particular we used the Mac computers to analyse data regularly. It would be helpful to have a good printer in the lab. It would also be helpful to have available prior to the trip an information paper describing the computing and other equipment/facilities at Scott Base. The Biolab in Q-Hutt is not deemed worthy of the name, and the facilities for biological research are poor. The provision of wannigans as laboratories was essential. Perhaps A-Hut could be converted into a proper Biological laboratory with wet facilities, bench space and balance and microiscope benches.