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Process 2 Cruise Final Update from John Marra 
Sun Apr  9 18:49:03 1995

We spent today, Sunday, April 9th, packing up after completing the last
station (30, the Arabesque site) yesterday. Just after breakfast this
morning, John Andrews hosted the Thorium Cafe on the fantail piazza,
patiently serving expressos and capuccinos to get us wired for putting
away the gear.

The onshore increase in productivity that we thought might happen never
occurred. In fact, the increases in chlorophyll were confined to 15-17N
(stations 19-26). North of that, the euphotic zone deepened. Even up on
the shelf in 90 m of water depth, the profile of temperature, salinity
and fluorescence looked very much like the top 80 m in the much deeper
water we had just left. At station 30, we took time for a MER cast, a
CTD to the bottom, and a last TM-rosette (for a PvI experiment).  The
water column again showed a fluorescence maximum at 40 m in a
temperature gradient: very different from the surface maximum in
chlorophyll seen last August (Chuck Trees). The nitrite max at 250 m
disappeared by 18N, according to Kathy Krogslund but re-appeared again
at the Arabesque site (sta30) further east.

The zone of higher productivity in the SE line is about the same
distance offshore as the maximum we saw on the NE transect. Of course,
we can't tell if this is a basin-wide feature or localized to each
area.

We think it will turn out that the NE transect will be the more
interesting, at least in terms of gradients. Whereas we saw little
trend in the SE line, there were order of magnitude and greater changes
in surface nutrient concentrations along the NE. But given that the NE
line was mostly the shorter hydro and intermediate stations, it was
difficult to appreciate the changes on the spot. We are miles away
before results become available.

We did 15 Double-MOCNESS tows, 15 Small-MOCs, 8 in situ primary
production exoeriments (28 on-deck), 86 CTD's, 90 TM-rosette casts, 61
Slurpers, 27 PvI experiments, 14 MERs, 11 Monster rosette casts, 26
PAR/INF profiles, 8 INF deployments, 12 grazematic experiments, 230
bacterial production experiments, 28 nitrogen productivity experiments,
and 12 days of dilution experiments and fecal pellet production
experiments. We also did 400-500 each of DOC analyses, HPLC pigments,
Turner chlorophylls, ap samples, POC's and PMC's, Fe and Al analyses,
CO2-system analyses, Iodine analyses, and AO bacteria counts.

Unlike to the south, there weren't any sharks milling around our
sampling gear at these last stations. We did see, however, an acrobat
show by a school of bottlenose porpoises as we steamed to station 26
(17N/58E).  They performed back flips, twirls, and tail-slaps in the
wake of the ship.  Captain Gomes also reported passing two large manta
rays a day later.


john marra is sci-01@thompson.ocean.washington.edu