Cruise Day 10
Speed 12 knots (kts)
Course 334° (NNW)
Location N. Chukchi Sea, approx. 225 nm NE of Wrangel Island, Russia
Depth 182 m
GO DEEPER DISCUSSION: (see previous journal for the questions.)
Hopefully you were able to observe enough clues to estimate your wind conditions on the Beaufort Scale. Today we are having Beaufort Scale 4 (moderate breezes) aboard Healy.
TODAY’S JOURNAL:
Wow, what a difference a day makes! Yesterday we were hanging on with a lively deck underfoot and today we are cruising along with almost no ship motion. Several factors changed as we sailed north last night- the wind dropped, the water got deeper, and we got closer to the pack ice (which dampens waves.) Before I went to bed last night I grabbed a screen shot of the map server after selecting the latest ice cover update, which showed ice not too far north of us.
Last night’s ice map showed us nearing the marginal ice zone.
This morning, I checked the ice update on the map server again, and it showed us right on the edge of the lowest concentration of ice. At nearly the same time I heard a bumping sound, and sure enough, when I walked out to look there was scattered ice floating around. The air had a bite to it, and light snow swirled around the fantail. It really felt Arctic today!
This morning the map server indicated that we had reached the beginning of diffuse ice in the North Chukchi Sea.
We saw the first sea ice of the trip this morning in the form of loose drift ice in the North Chukchi Sea.
Along with the ice came another wonderful surprise this morning. I was walking along the starboard side, heading forward to have a look around from the bridge when I noticed that some of the ice floes had big brown things on them. Peering through binoculars, I saw that they were walruses! For a little while we passed through lounging groups of these giant seals (only elephant seals are larger within the seal family.) Most just watched us go by, but some of the closer walruses decided not to chance it and slipped into the water.
Walruses on ice floes, North Chukchi Sea.
Walruses on ice floes, North Chukchi Sea.
Today is another very busy day of science sampling stations. I was up early, in time to report on deck by 06:00 to photograph Paul Aguilar deploy a pair of drift buoys. Drift buoys are oceanographic instruments that float on the surface and report their position to satellites. By watching how they move, oceanographers can track surface current direction and speed. Two types were put overboard today. The first has a 25-meter long cable with temperature sensors spaced along it that hangs under the buoy. So as this one drifts, it also can remotely report the temperature profile of surface water as it goes. The second has a long fabric drogue that unfurls beneath it once it is in the water. This helps it more accurately follow the surface currents with less influence from the wind on its movement. I suspect the scientists monitoring these buoys will be interested to see how the motion of one compares to the other, as they were launched within a few meters of each other.
Two drift buoys are readied for deployment in the Chukchi Sea.
This cable has temperature sensors along its 25-meter length so it can report a surface temperature profile along with its position as it drifts in the Arctic Ocean.
This drift buoy has a drogue, which is coiled up for deployment. As seawater dissolves the cardboard bands the drogue will unfurl down underneath the buoy into the water column so the buoy’s movement will more accurately reflect the surface current motion and be less influenced by the wind.
Paul Aguilar calls the buoy monitoring group by satellite phone to see if they are receiving signals from the drift buoys. Good news- they were!
The buoy launch was just the beginning of the many sampling operations taking place today over 3 (and possibly the beginning of a 4th) stations. The team is very interested in seeing what dynamics trace elements will show as we transition from open water into ice. This transition area is called the marginal ice zone (marginal means edge.) This represents brand new science, as nobody has undertaken this kind of study in a marginal ice zone before. So as we cross from open water into more solid ice, all of the tools aboard will be deployed to gather samples. We have already done several CTD casts today, had the small boat go out to pump surface water samples away from the Healy, and pumped in water from the mixing layer 7m deep (a transition zone between surface and deeper water.)
GO DEEPER!
Walruses are perhaps most famous for their long tusks, but their whiskers are also iconic. What do walruses use their whiskers for?
Aloft Con web cam updated every hour
Healy Track
That's all for now. Best- Bill