Southern Ocean Iron Experiment (SOFeX) Cruise
January 5 - February 26, 2002
January 12, 2002: Day 8
Latitude: 56 30.00 S, Longitude: 172 00.00 W
Ken Johnson writes: Hey, the show is starting.We recovered the iron sampling fish in a large sea and at 1100 this morning we launched the drifting buoy that will mark the experimental location. The drifter is equipped with chemical sensors for nitrate, oxygen, carbon dioxide and phytoplankton fluorescence. Its position is reported back to the ship every 5 minutes and chemical properties of the water are monitored every hour.
We will use this system to study changes in the phytoplankton community. If the phytoplankton start to grow after we add iron, they will have to consume nitrate to produce the amino acids required by all living organisms. Increased photosynthesis will produce oxygen and consume carbon dioxide. Eric Drake and Pete Strutton of MBARI are the gurus of the drifter. The systems began working perfectly after launch and the sensors are reporting a nitrate concentration of 22 uM and a carbon dioxide partial pressure of 372 uatm.Both agree very well with the values being monitored on board the ship.
The day started with a solid 40 knot blow. I spent the whole night airborne in my stateroom as the shipped pitched over 4 to 5 m seas.Im still trying to figure out why they give the chief scientist the worst location to sleep on the ship. Hmmm. Now, its a great room, but its 3 decks up from the main deck. If were bouncing down below, think what its like up above. The small staterooms below deck are good because there is always something to hold on to. To get from my bunk to the head, I have to cross about 5 m of open space with nothing to hold on to, while the ship lurching back and forth at an incredible rate.Wow, its like getting launched out of bed into a magnitude 7 earthquake.
Right now, were well into the pre-fertilization sampling station. About 5 more hours and we begin adding iron. The ambient iron concentration is 0.1 nM. Well add enough iron to a 15x15 km area to raise the concentration to 1 nM. They well do that one more time before we depart to create the south patch. Well add iron again to the north patch on our return.