FRAM-2014/15 - The second week of ice drift

(8. - 14 Sept. 2014)

Ice drift and camp life

The ice drift after Polarstern's departure was first a 9 nautical mile(nm) loop to the east, then a 6 nm loop to the north and by Tuesday 9 Sept. we passed the position where Polarstern had left us. All this motion is driven by the local wind field and in general terms opposite or perpendicular to the long term ice drift. As of Sunday evening 14 Sept., we are in the Makarov Basin about 22 nm from the foot of slope of Lomonosov Ridge, heading north. The water depth is 4.000 meter. All this is actually a gift to us, because it gives us time to build a base camp with work space for the winter. The base is a 80 square meter (sqm.) area to house the hovercraft plus two annexes each 12 sqm.; one for geological sampling and one for storage. In addition there will be a small generator room. The ice and snow walls are 40 centimeter thick and 2 meter high, and the top will be covered with a tarp. The building method is shown in a short time-lapse movie attached. After 8 days of hard work, the storage room is left to do. We had clear skies today Sunday. The temperature dropped to minus 17 Centigrades (minus 26 C considering the wind chill factor), so shelter is important for the work environment. Surprisingly enough, this simple form of camp construction has, to the best of our knowledge, not been reported by expeditions on drifting sea ice.

The hovercraft is parked on 10 x 10 cm lumber on top of a pallet in the front and one in the back. Heat from the cabin part of the hull turned out to melt the ice underneath. The problem was remedied by moving the support forward and towards the rear plus allowing cold air to circulate under the craft.

Science

Today, we made a hole in the ice 15 meter away from the hangar and deployed the Acoustic Doppler Current Profiler about 2 meters below the underside of the ice. This instrument is programmed to start operating 15 September and will send and receive acoustic pulses which give information about ocean currents from the underside of the ice down to about 500 meter depth. In addition we have one current meter hanging from the ice at 800 meter depth and a second one at 2.000 meter depth.

A 1 m x 1 m hole is made through the ice in preparation for geological sampling. So far only the 3.5 kHz echo sounder is in continuous operation. The penetration over the abyssal plain is about 20 meter. Five autonomous echo sounding buoys are in operation on our ice floe (6 km in diameter) using data transmission directly to shore via Iridium. In the vicinity of 87 18.9' N, 159 21' E, the 3.5 kHz signal weakened and "disappeared" for about 10 hours, suggesting we passed over a narrow mountain peak coming out of the flat sea floor of the abyssal plain. This feature is not on any bathymetric map.
The sensors of the weather station and the radiation flux instruments are running well, but hoar frost is being continuously deposited. We visit the sites 2-3 times a day to check and clean.
No form of animal life has been observed during the week.

All is well.

Yngve Kristoffersen & Audun Tholfsen

Daily reports
Monday 8 September.
Position: 87 22.6' N, 154 43' E, temperature - 8 C, air pressure 1002 hPa, wind 15 knots from W. Winds calmed down and clear skies from noon - a beautiful day in the afternoon. Worked all day cutting ice blocks and building the forward wall next to the hydro hole. Have drifted 6 nm south during last 24 hours.

Tuesday 9 September.
Position: 87 21.1' N, 155 10' E, temperature - 9 C, air pressure 1001 hPa, wind 2 knots from WSW. Overcast and white-out. Wind increased to 15 knots during the morning with blowing snow. At midnight, we passed the position where Polarstern dropped us off 9 days ago. Ice walls for the geological sampling area completed. Put out extension cable to rad-flux instrument so the battery is charged every time the generator is run.

Wednsday 10 September.
Position: 87 21.3' N, 157 18' E, temperature - 6 C, air pressure 1002 hPa, wind 8 knots from SE. Drifting due west at 0.2 knots. We are 7 nm from foot of slope of Lomonosov Ridge, water depth 4000 meters. The sun has been breaking through the clouds all day. Completed aft ice wall on the port side.

Thursday 11 September.
Position: 87 21.7' N, 158 11' E, temperature - 4 C, air pressure 999 hPa, wind 11 knots from W. Overcast and white-out. Cleared later in the day and temperature fell to - 13 C. The hovercraft is tilting 2 degrees forward from melting of the ice below the cabin part of the hull. Started the engine and put the craft on the columns in order to position reinforced pallets as far forward and towards the rear as possible. Started work on long ice wall on starboard side.

Friday 12 September.
Position: 87 19.0' N, 159 21' E, temperature - 10 C, air pressure 1007 hPa, wind 5 knots from SSW. Completed the long ice wall and three layers on the front wall. The 3.5 kHz signal weakened and "disappeared" about midnight and came in strong about noon. We must have passed a basement peak protruding out of the Makarov abyssal plan - a feature not shown on the IBCAO map.

Saturday 13 September.
Position: 87 16.9' N, 160 13' E, temperature - 6 C, air pressure 1019 hPa, wind 1 knot from SSW, fog. Completed the front ice wall and half of the forward wall on the port side. Visited the weather station and the rad-flux instruments twice during the day to remove hoar frost from the sensors.

Sunday 14 September.
Position: 87 19.0' N, 161 49' E, temperature - 15 C, air pressure 1017 hPa, wind 5 knots from ENE. Sunshine from a cloud-free sky in the morning. After lunch, fog and white- out. The ice drift is 0.2 knots towards NE. Completed ice wall on port side. Started on ice walls for the storage room on starboard side. Visited the weather station and the rad-flux instruments three times during the day to remove hoar frost from the sensors. Audun turned 42 years today. The event was celebrated with rump steak for dinner followed apple cake at coffee/tea.

Location of FRAM-2014/15

Deployment of the acoustic Doppler current profiler.