Dutch JGOFS - Underway measurements during the North Atlantic Pilot Project (NAPP)

The North Atlantic Pilot Project (NAPP), also known as the North
Atlantic Bloom Experiment (NABE), was the first field work of JGOFS
(Joint Global Ocean Flux Study) and it served as pilot study for the
proposed North Atlantic Process Study. Six countries participated in
this study: Canada, France, Germany, The Netherlands, UK and USA

The Netherlands contributed to NAPP with four cruises on board
R.V. Tyro:
1. Leg 1, 31 July-11 September 1989 (Upper Ocean Processes)
2. Leg 2, 13-28 September 1989 (Benthic Processes)
3. Leg 3, 17 April-31 May 1990 (Upper Ocean Processes)
4. Leg 4, 2-29 June 1990 (Benthic Processes)

The sea surface conductivity was recorded continuously by a Seabird
thermo-salinograph which was flushed by means of a pump-system.
The salinity of surface waters was recorded by a Seabird thermosalinograph
that was flushed by means of the deckwash pump. Temperature was measured
with a calibrated Pt-100 resistance which was mounted in the main cooling
water inlet. Temperature and flourescence has been recorded continuously with
a strip chart and with a data acquisition computer from Madeira and on.

A special interface card combined with the data acquisition module gave
one minute measurements and registrations of chlorophyll a, temperature,
date, time, position, heading and speed. Whenever possible TCO2 measurements
of the surface waters have been made with an interval of approximately 6
minutes. After the cruise these two separate datasets will be combined into
a final sea surface data base. The fluorescence meter is not calibrated at
the NIOZ. Raw data files were continuously saved. For calibration
of the (new) TCO2 online measurements samples were taken regularly with
either the rubber boat of if convenient with the CTD rosette sampler.
Their appears to be a strong diurnal rhythm in the TCO2 data.