March 13, 2001 to June 2, 2001
Monterey to Hawaii and back
May 25, 2001: Leg 5; Day 4
Ken Johnson writes: The wind is picking up a little with white caps and a small sea that we're heading straight into. The ship speed is back to 8.5 knots as we head to our fourth station, which will be a little past our target of 27o 00' N, 146o 30' W. We're at 26o 12' N, 148o 38' W right now and we'd arrive on station at 2 a.m. The exact location is not critical,so we'll go a little past and do the cast at sunrise. There is not a lot of enthusiasm for a station in the middle of the night.
We're busy collecting data, even busier fixing instrumental problems. A valve failed on the aluminum system yesterday. I thought I would find which of the three electronics modules in the valve was bad by swapping them into Ginger's iron system. Oops, that fried her valve too. Steve has fixed the aluminum system with a little 'MacGyver'-style engineering and Ginger's system is now working again, but with no valve position display, which keeps her on her toes. I wasn't too popular yesterday for that one. Chalk it up to experience.
Despite the problems, data are rolling in. Ginger and Josh have analyzed the first vertical iron profile. It is identical to a profile collected during the month of September during the VERTEX program at depths below 400 m. However, our profile during the high dust input season has a nice maximum at the surface, while the September profile, which was collected during a low dust time of the year, does not. Is that a dust input signature? We'll have to keep collecting more data. Surface water iron and aluminum concentrations, that we sample with the towed pumping system, are also elevated when we compare them to concentrations measured at the same locations on the out bound leg of the expedition. We'll plot that data up when we get things a little more under control. Time for lunch. That's all for now.