Position: , 3350 meters above sea level
Maximum & Minimum temperatures: - 27 to - 32 °C
For the first time in weeks, strong winds and blowing snow were with us all day. In these cold, dry snow conditions, it takes a wind speed of approximately 5 m/s (10 miles per hour) for the snow to start being transported by the wind. As the snow particles bounce and roll along the surface they are exposed to the dry air above and continually sublimate (go from solid ice to vapor) as they move along with the wind. The snow particles can be blown about 3 km (2 miles) before they sublimate/disappear completely.
Winds in this area of Antarctica come from two different sources: large storms that are similar to winter storms back home (but much colder!), and katabatic flow. Katabatic winds occur when cold, dense air near the snow surface flows down-slope under the influence of gravity. Since leaving the Pole of Inaccessibility we have been moving down hill, so as we descend farther down the slope of the Ice Sheet we expect the katabatic winds to increase.
- Glen
Photo caption:
Windblown snow particles spinning past a little snow rib (Photo: Stein Tronstad).
This contribution is from the log of the Norwegian-US Scientific Traverse team, who are en route from Troll Station to South Pole Station. Much more information can be found here.