Cruise Day 61
Speed 17 knots (kts)
Course 244° (WSW)
Location Chukchi Sea, ~100 nm W of Barrow, Alaska
Depth 48 m
GO DEEPER DISCUSSION: (see previous journal for the questions.)
By running in the same direction as the wind, a ship can reduce the •relative wind speed.• For example, if there is a 25-knot wind and the ship goes 10 knots in the direction of the wind, the relative wind on deck will be 15 knots (25 - 10.) Aircraft carries do the opposite trick, steaming into the wind to increase the relative wind speed. (Stronger headwinds give airplanes more lift, so they can take off easier and also land with the help of the wind slowing them down relative to the carrier deck.)
We are running southwest through the Chukchi Sea after an overnight diversion towards Barrow, Alaska. We made the detour southeast to meet the USCGC Cutter Waesche, which sent one of their HH-65 Dolphin helicopters to pick up a crew member for transfer to Barrow. The Waesche is another large Coast Guard ship, a 418-foot long National Security Cutter detailed to the Chukchi and Beaufort Seas this summer. I could only see the Waesche distantly on the horizon, but the helicopter was pretty cool to see coming and going. The HH-65 Dolphin is smaller than the Jayhawk that came yesterday but also has a rescue hoist. It’s tail is very distinctive, with an enclosed ducted-fan fenestron instead of a tail rotor that is seen on most helicopters. After the transfer we turned west to follow Alaska’s northern coastline around into the mouth of the Bering Strait. There are two stations in the strait that we’d like to repeat tomorrow if time and weather permit, but both factors aren’t looking great and for now the stops are considered “doubtful” according to the whiteboard that shows upcoming events and schedules for stations.
A few days ago I detailed the multicore sampler operation (10-5-15 “Multicore”), and ended by showing how sampling operations aren’t always successful. I’m happy to report that we tried multicoring again yesterday, this time recovering samples from the sea floor on the Chukchi Shelf. It was still tricky going, with the first few tries coming back empty as they did on 5 October. But on our final try, the ship was standing still enough over the bottom for two of the multicore tubes to capture sediment. Additionally, the Niskin bottle recovered water from just above the sea bed, a zone where the regular sampling rosettes cannot safely operate. (Accidentally lowering them into the bottom can damage the sensors on the rosette and kink the cable as tension comes off of it, necessitating re-termination.)
During the last ice age, even an icebreaker could’t be traveling where we are now. Why not?
That's all for now. Best- Bill