Porcupine Abyssal Plain (PAP)

Latitude and Longitude: 49N,16.5W

Depth: 4800m

Oceanographic Region: Northeast Atlantic

News: The PAP site moorings and time-lapse camera system were successfully maintained in September 2010 on the RV Celtic Explorer. See data page for real-time transmission.

History of the Site:

Since 1989, this environmental study site in the Northeast Atlantic has become a major focus for international and interdisciplinary scientific research and monitoring including water column biogeochemistry, physics and benthic biology. The first autonomous equipment include the sub-surface sediment trap mooring and the Bathysnap seafloor time-lapse camera system (both since 1989). Since 2002, a full depth multidisciplinary mooring has been in place with sensors taking a diverse set of biogeochemical and physical measurements of the upper 1000m of the water column. In 2010, a collaboration between NERC and UK Met Office has led to the first atmospheric measurements at the site. See the full parameter list below for atmospheric and ocean data and the data frequency and transmission status.

Parameters measured: *indicates data transmission in near real-time

ATMOSPHERIC (UK Met Office ODAS Buoy)

Parameter	Depth	Sensor	Frequency
*wind speed and direction	3.5 m asl	Gill acoustic sensor and revolution magnetic compass	hourly (10 min ave)
*relative humidity	2 m asl	Rotronic Hygroclip R/S sensor	hourly (instantaneous reading)
*air temperature	1.5 m asl	Electrical Resistance Thermometer (ERT)	hourly (10 sec average)
*sea temperature	1 m (subsurface)	Electrical Resistance Thermometer (ERT)	hourly (10 sec average)
*atmospheric pressure	1.75 m asl	Druck RPT350 pressure sensor	hourly (20 sec average)
*significant wave height and period	surface	Datawell heave sensor; 17.5 min average	hourly (over 17.5 min sample)

SURFACE OCEAN (full depth mooring. 25m indicates multidisciplinary sensor frame)

Parameter	Depth	Sensor	Frequency
*Temperature	25m	Seabird Microcat	30min
*Salinity	25m	Seabird Microcat	30min
Nitrate & Nitrite (Chemistry)	25m	EnviroTech NAS	Not functioning since Sept.2010
*Nitrate & Nitrite (UV absorption)	25m	Satlantic ISUS	4hr
*Chlorophyll	25m	WETlabs (FLNTUSB) / (Seaguard-Cyclops)	6hr/1hr (only WETlabs in near real-time since Sept. 2010)
Dissolved Oxygen	25m	Seaguard optode	1hr (no real-time since Sept. 2010)
Currents	25m	Seaguard (DCS s/n 69)	1 hr (no real-time since Sept. 2010)
*CO2 (IR absorbance after equilibration)	25m	PRO-OCEANUS	4hr (NB. 2-way communication)
*Dissolved gases	25m	PRO-OCEANUS (Gas Tension Device)	4hr (NB. 2-way communication)
*Radiance	25m	Radiometer (upwelling; 7 channel sensor)	4hr
*Irradiance	1m	Radiometer (total irradiance; 7 channel sensor)	4hr

DEEP OCEAN (separate sub surface mooring)

Parameter	Depth	Sensor	Frequency
Particle flux (Sediment trap)	3000m	McLane Sediment Trap	Variable (days)
Currents	3000m	Seaguard RCM9	4h
Particle flux (Sediment trap)	3050m	McLane Sediment Trap	Variable (days)
Particle flux (Sediment trap)	4700m (100 m above Seabed)	McLane Sediment Trap	Variable (days)
Currents	4700m (100 m above Seabed)	Seaguard RCM9	4h

Benthic studies:

Parameter	Depth	Sensor	Frequency
Images	seafloor (4800m)	Digital camera on Bathysnap lander	8 hr (no near real-time)

In May 2010 a benthic observatory was deployed with multidisciplinary sensors for the ESONET project MODOO. This led to a successful testing of an acoustic telemetry link from the seafloor (4800m) to the mooring line. However technical problems led to transmission being lost. Recovery of the lander system is planned in 2011.

See websites

http://www.noc.soton.ac.uk/obe/PROJECTS/DEEPSEAS/

http://www.modoo.info

Enhancement/Modifications conducted within EuroSITES:

Continuation: Real-time and delayed-mode data on PCO2, Chlorophyll, nutrients, water column physics and downward particle flux. Benthic biology including Bathysnap time-series camera system.
Enhancement to long-term time-series: O2 , radiometers (radiance)
Short-term trials: oxygen consumption - trials of IODA6000 on fixed and drifting moorings (CNRS; 2009); first deployments of osmosampler at PAP (NOC; 2009); trials of mesozoplankton sampler McLane ZPS (NOC; 2009-2010); seafloor lander and acoustic telemetry (ESONET MODOO project May 2010)

Contacts:

Principal Investigator: Professor Richard Lampitt (rsl@noc.soton.ac.uk)
Scientists involved: Dr. Thanos Gkritzlais (sensors, engineering, chemistry), Sue Hartman (chemistry); Dr. Henry Ruhl and Dr. David Billett (benthic studies), Corinne Pebody (sediment traps)
Data manager: Maureen Pagnani (mred@noc.soton.ac.uk)

Links to related websites:

http://www.noc.soton.ac.uk/pap/

http://www.noc.soton.ac.uk/obe/PROJECTS/DEEPSEAS/

EuroSITES is a FP7 Collaborative Project coordinated by the
National Oceanography Centre, Southampton, UK

Call FP7-ENV-2007-1, grant agreement N° 202955
Sub-Activity 6.4.1. Earth Observation; Monitoring the ocean interior, seafloor, and subseafloor