Our frozen ocean platform
Once a week we head out to four different sites at Mawson and use a small hand auger to drill through the ice. We also measure how thick the snow is on top of the sea ice. Snow is a very good insulator, so once it covers the sea ice it slows down the rate of heat loss from the ocean to the atmosphere, which slows the growth of ice underneath. We then use a tape measure to find the ice thickness and to check the depth of the ocean below the surface.
For the last month, the ice in Mawson Harbour has been growing about 10cm a week and is now over 90cm thick. To visit all the sites is about a 6 kilometre walk and can be quite a delightful half-day out. Last week we had perfectly calm conditions, with a pale pink sky and mountain views in the distance.
What the new sea ice growth means for life at Mawson is that soon we can start to venture out along the coast in both directions. Until now we have been confined to foot travel, but in the next few weeks we will be able to drive vehicles on the ice as well.