PROcesses of Vertical Exchange in Shelf Seas (PROVESS)

Multicorer deployment
Multicorer deployment ©

PROVESS aimed to combine experimental, theoretical and modelling studies to improve the understanding of vertical exchange processes in the water column. In particular, at the surface and benthic (sea floor) layers and across the pycnocline — a layer separating water of different densities.

It also explored mechanisms of physical-biological coupling in which vertical exchanges and turbulence significantly affect the environmental conditions experienced by the biota (flora and fauna).

Who coordinated the project?

PROVESS was coordinated by John Howarth of the Proudman Oceanographic Laboratory (POL) and involved scientists from eight European countries. It ran from March 1998 to May 2002 and was funded by the European Commission through the Marine Science and Technology (MAST) III programme.

BODC was responsible for the management of all data arising from the project.

Field campaign

The experimental phase of the project was carried out at two contrasting sites in the North Sea. Measurements were conducted at the northern site (NNS) between September and November 1998 and at the southern site (SNS) from March to May 1999.

At both locations, measurements were concentrated at a central position. Moored instruments were deployed for a period of three to four months and were supported by extensive measurements collected during seven oceanographic research cruises. Additional measurements were also collected to estimate horizontal gradients.

Data parameters sampled

Basic multidisciplinary measurements taken included

  • Physical (e.g. temperature, salinity, optical backscatter, current speed and direction, turbulence dissipation)
  • Meteorology
  • Bathymetry
  • Chemical (e.g. dissolved oxygen, organic carbon and nitrogen, nutrients)
  • Biological (e.g. biomass, pigments absorption, microplankton taxonomic composition)
  • Geological (e.g. sediment cores)


Some of the equipment employed during the PROVESS field campaign included

  • CTD with fluorometer, oxygen probe, underwater PAR sensor and transmissometer
  • Water bottles — water samples at specific depths
  • Underway — continuous measurements of sea surface (salinity, temperature, attenuance, chlorophyll, nutrients, etc), meteorology, navigation and bathymetry
  • Offshore meteorology stations
  • Turbulence dissipation profilers
  • LISST — laser particle size profiler
  • Multicorer
  • Moorings / landers — current meter, ADCP, thermistor chains, bottom pressure recorders and STABLE

Data management goal

Our main goal was to provide harmonised management of the field data. Both for the benefit of the project scientists and to ensure that PROVESS left a legacy of fully documented archived data for comparative studies in years to come.

BODC recovered over 94% of the data collected during the field programme. The data were processed, quality assured, documented and incorporated into our relational databases.

The PROVESS data set

The PROVESS data set is published on the PROVESS CDROM which consists of three main components

  • the relational database
  • the underway data set
  • the moored instrument data set

A software interface, developed at BODC, is also available to ease data extraction. Data from vertical profiling instruments and discrete sampling have been integrated into a relational database interfaced with BODC Database Explorer software. Time-series data are available in ASCII or binary files interfaced with BODC's Mooring Explorer and Underway Explorer software. The data are accompanied by a comprehensive Users' Guide.

In addition, the source code (FORTRAN 77) for the PROVESS Water Quality Model (PROWQM), a one-dimensional integrated model, is also provided. This was developed during PROVESS to provide a platform for the testing and validation of new and existing schemes for turbulence and modules for biology and sediments prior to their implementation in three-dimensional numerical prediction models.

The data are also held in BODC’s databanks so subsets may be obtained by request from the BODC Enquiries Officer.

European Commision Marine Science and TechnologyProcesses of Vertical Exchange in Shelf Seas