We are at the ice edge! After 10 days of Southern Ocean travel we are now in calm waters and steaming through increasingly dense fields of broken ice. We are frequently observing snow petrels, an ice-loving species, and have also seen the first seals, including a rare Ross seal hauled out on a small and rocking ice floe.
Our team, coordinated by Petra Heil and supported by many volunteers, has started standardised ice observations. These are hourly observations of the sea ice conditions along the ship’s path. Observers describe the amount of different ice types and their physical properties. For three main ice types we describe aerial coverage, thickness, mean floe size, and snow cover. Observations take place from the ship’s Bridge and we use a ‘Norwegian’ buoy lowered over the side of the ship as a scale (see photo), to measure the thickness of overturning ice floes.
Standardised ice observations — following the international ASPeCt protocol – have been conducted since the mid-1980s and have significantly contributed to the understanding of the dynamics of Antarctic sea ice. For example, while satellites are good for observing sea ice extent, they are currently not able to properly determine the thickness of Antarctic sea ice.
Ice thickness observations collected during voyages conducted by many different vessels and over many years have filled this gap, and have helped to produce large-scale maps of Antarctic ice and snow thickness. The ship-based ice observations that we are making will contribute to a large historical dataset that is used to validate and test emerging satellite products and sea ice physical models for the Southern Ocean.
Today we had our first muster with full Antarctic gear. When the drill signal was given, all expeditioners went to their cabins to get geared up and grab their survival bags. It was quite tight in our cabin, with three people putting on their bad weather gear and life-vests at the same time. There was also a bit of an orange-yellow traffic jam on the way to our main muster station on the heli-deck.
This afternoon we had a spell of nice weather and spent our free time on the bow and the Bridge to watch the rapidly changing icescape with a sea-ice cover of 20–30% and many icebergs. The ship is getting increasingly busy with planning meetings and further inductions for the re-supply of Davis. Depending on the ice conditions we hope to arrive at the station in about four days.
Klaus Meiners — Chief Investigator