What tells you of the change of season at home?
Turning a page on the calendar? The fall of a leaf or bloom of a flower? An extra jumper or pulling the winter quilts out of the cupboard? The sun setting later after you get home from work, encouraging the evening walk?
Temperature and light are the main seasonal variations for life on the ice. Animals visit for a short time, but they are only in small numbers around station so they are less visible as indicators. The temperature definitely changes during the year but initially we put multiple warm layers of clothing on because we aren’t acclimatised, even to the relatively mild “summer” temperatures. When the winter wanes to similar temperatures later in the year we won’t require the same number of layers. But Antarctic work-wear is limited in it’s fashion range so that is not too visible either.
The light on the other hand changes daily. When we arrived in early February the days were almost 18 hours long, the sun rising about 4am and setting around 10pm with a long twilight. Now in mid-March we are close to the equinox and the 12 hour day. In just over a month we’ve lost six hours of the sun above the horizon. By June we will completely lose it’s bright face for a few weeks.
Each day offers delight in the play of light across our local landscape. Icebergs appear to change shape as their faceted surfaces are set alight by the sun. The early light of day highlights the sharp cut of crevasses and dark folds of snow gullies on the hill behind the station. The deceptively soft blue of solid ice is picked out during the day, shading to sunset pinks reflecting off snow patches in the late evening. In the dim light of twilight the icy plateau still glows, as if holding the sun’s last rays within.
With some cold temperatures and light winds, Mawson has been growing ice over the open water of Horseshoe Harbour and surrounds. For a few days during the week it seemed to grow as we watched. Some stronger winds have blown the fresh ice away from Kista Strait at the moment but Horseshoe Harbour is holding for now.