Southern Ocean Iron Experiment (SOFeX) Cruise
January 5 - February 26, 2002
Logbook
January 14, 2002: Day 10
Drifter: -56 8.6358-171 58.326
Ship: -56 8.0652-171 50.547
Ken Johnson writes: Its a quiet day.Were still pumping iron until about 0300 tomorrow morning when the iron in the big 15,150 liter (4000 gallon) tank will be all gone.The level is down to less than 1/3.The weather has been quite nice (for 56 S) with a little sun this afternoon, winds under 10 knots.Well know its really cold when Josh puts long pants on.
The patch took off to the north like a rocket after we put it in, but it has slowed way down and moved very little today.Whew!Thats a relief, as the SAF is not that far to the north.
Not much else is happening.We have secured all the underway sampling systems, including the ships flow through system, to avoid contaminating them with large amounts of iron or the SF6 tracer that we add.SF6 is the "air" found in Nike Air running shoes.All those fluorines make it very electronegative and it can be detected at fantastically low levels in a gas chromatograph.Its so inert that it doesnt react with anything in the seawater and we can use it to track the patch long after the iron is gone.
The ships engineers are busy rewiring a 480 Volt supply for the SeaSoar.The main generator seems to produce noise in the same frequency range that the SeaBird CTD on the SeaSoar uses for its communications.An auxillary generator forward in the ship has a much cleaner 480 V supply and so theyre wiring that back to the aft end of the ship.Well begin a SeaSoar survey of the patch tomorrow morning at 7 am, so everyone is rushing to complete the job.
