February 12^th 2004
Lat.: 70º03'N
Long.: 126º18'W
Air temperature: -30ºC

This week, we have had blowing snow. Piqtu, piektuk, and bectoak are three of the alternative spellings we have heard for the Inuktituk word for blowing snow, while the French term is “poudrerie”. The winds of 30 knots and resulting snow effects have delighted some of us (especially the snow team of Peter York and Sergiy Savelyev, York University), but they make field work on the ice a little more difficult. The strong winds and drifting and blowing snow can lead to the formation of sculpted erosional forms called sastrugi, as winds close to the ground start to erode the base of existing snowdrifts to produce the sort of layered structure seen below. To quote Sergiy, “If no fresh snow is available, the biting winds file away snow from mature snow banks and nothing can withstand its force”.

Sastrugi on the red flag-marked road to Takatuk. The ship is behind us in this image and the study site with Parcoll tent and sensor towers visible in the distance. (photo: Sergiy Savelyev)

The term sastrugi comes from the Russian word zastrugi, meaning “shaped with a knife”, which has been applied to this type of feature in the Antarctic. Although the sastrugi we have seen here are relatively small, they often grow to several meters in height as snow is blown around by strong winds.

Blowing snow and blizzard conditions are, of course, a hazard. Teams working on the ice always take precautions against getting lost or trapped in a storm by carrying a GPS (global positioning system) unit with them (see below), as well as radios, emergency rations and shelter. The GPS units work well in general but are not always functional at temperatures of –30°C and below, as we are experiencing during this leg. Keeping the GPS cozy and warm, well inside one’s layers of clothing, and using an external antenna on a shoulder is an effective way of ensuring that you know where you are. In this area close to the magnetic North Pole, the traditional compass is not very reliable.

Carrie Breneman (University of Manitoba) finding her way home in the snow. The relatively warm GPS unit has just been pulled from within her parka (note the absence of snow or ice on it). Note the antenna strung on her shoulder. (Photo: Mike Suitor)

The major “highways” and research areas that we have established on the ice have been mapped (see route to Takatuk below) and marked by flags. In addition to not getting lost, it is important for travelers on the ice to keep away from areas where natural snow and ice conditions are being studied, as well as from areas reserved for researchers on subsequent legs.

(Original Map: Alex Langlois)

Map of near-ship locations, initiated during Leg 3 and fully established and equipped during Leg 4. The letter “A” marks the landing strip constructed and maintained to accommodate crew changes and cargo drops. “B” is an area reserved for near-ship electromagnetic snow measurements. Immediately east of B, alongside the bow of the ship, is where we have cut a large hole in the ice twice now for boxcoring the seabed (as featured in an earlier dispatch). “C” is Bruny Island, where snow measurements are made and a chamber for gas measurements installed. The two “D”s are Dukuduku, holes in the ice for biological sample collection and under-ice trawling, while “E” is Titicaca, a site for water sampling now protected by a hut. “F” marks the easterly site we have named Takatuk, the main area, complete with heated Parcoll, for our interdisciplinary sea-ice and snow studies. There are other “roads” heading N, S, E and W for the snow surveying and bear habitat teams and a major highway 18 km long (16 km as the crow flies, if we had any crows!), heading SW to the Ice Camp, established near the mouth of the Horton River, called Angaguk (featured earlier for the large-scale under-ice zooplankton net tows being conducted there).