P06 leg 1 Week 3

by Sabine Mecking and Isa Rosso
(chief and co-chief scientists of P06 Leg 1)

RVIB N. B. Palmer, NBP17-06/P06 Leg 1: Weekly Scientific Report 03
31.90°S, 178.31°E
10:30pm, Monday, 24 July 2017 (local time and day)
air: 16.1°C, water: 17.9°C, winds: 8 kn from SW
on station 80

During the past week, our daily routine of one CTD station after another was
interrupted by a couple of delays. Weather protection by New Zealand was,
unfortunately, not as good as we were hoping. A big storm that started in the Tasman
Sea wrapped around New Zealand, basically following our cruise track. Operations were
put on hold Thursday afternoon while seas were building and wind gusts were up to 50-
60 knots. We managed one CTD station (#77) on Friday afternoon. But with the
weather forecast worse for Saturday, CTD operations were stopped again throughout
the night. On Saturday morning, we also received notice that a medevac was necessary
for one of the crew members. What followed was a bumpy ride toward New Zealand,
with wave heights at 6-8m and some even bigger rollers, and a speedy evacuation of the
ill seaman by helicopter about 100 miles north of New Zealand. We are glad that he
could make it to the hospital safely and wish him well for his recovery back home.
By 10am (local) on Sunday, we were back on our way to station 78 (South Fiji
Basin) that was moved several times to increase station spacing and to make up for
some of the lost time, amounting to a total of ~3.5 days due to weather and medevac.
Other stations along the planned cruise track are being adjusted as well. CTD station
work resumed this morning (Monday) at 6am. We are looking forward to finally
reaching the dateline and the Kermadec Trench (KT), including the deep western
boundary current flow along the adjacent Tonga Kermadec Ridge (TKR), all in the New
Zealand EEZ, in the next few days!

Measurement groups used the unexpected break to catch up on samples, to fix
some problems with their systems (CFCs and alkalinity), and to get a little bit of rest
before the next 3 weeks of (hopefully) non-stop stations. While the weather was rough,
nobody got seriously sea sick, and some of the students outright enjoyed the big rollers
because it made their first sea-going experience feel more “real”. During this time, we
also had the chance to celebrate the only leg 1 science party birthday (Manuel
Belmonte, alkalinity analyst extraordinaire) with cake, gifts, and songs in >5 languages.
Preliminary comparison of profiles of various properties between stations and
with previous P6 occupations suggests that the quality of most data is very good. The
CTD rosette also continues to function well. The biggest problem/danger last week was
a lanyard that snapped when the bottom end cap of one of the old Niskin bottles was
being set, with the result of the spring flying out at the top. As a precaution, all of the
seven old bottles that had been mounted to test for CFC contamination (a false alarm)
were exchanged back against the new Niskin bottles.

As we continue to occupy stations and examine data over the next few weeks,
wish us luck that operations go smooth so that we do not experience any further delays.
Danke schön!

- Sabine Mecking and Isa Rosso