A Review of SOTEAG Monitoring Data and Other Long Term Environmental Series from Shetland


This project was undertaken in collaboration with the University of Aberdeen, on behalf of the Sullom Oil Terminal Environmental Advisory Group (SOTEAG). The aims of the work undertaken by NAFC were:

  • To review the results of the long-term marine environmental monitoring programme undertaken by SOTEAG
  • To identify and collate other relevant long-term environmental data series from the waters around Shetland
  • To examine these data series for any evidence of long-term trends and/or periods of rapid environmental change in Shetland’s marine environment, and for evidence of relationships between the different series

The project also included a similar review of climatological data, undertaken by the University of Aberdeen and the Environmental Research Institute in Thurso.

Start Date and Duration

The project ran from September 2009 until the end of 2010.


The project was co-funded by the Shetland Islands Council, the NAFC Marine Centre and SOTEAG / the Sullom Voe Association.

Download the Project Report

Dawson, A., Napier, I., Davies, N., McIlveny, J. (2011). A review of SOTEAG monitoring data and other long term environmental series from Shetland. Sullom Oil Terminal Advisory Group (SOTEAG) Report.

Executive Summary

The programme of environmental monitoring undertaken by SOTEAG over the last 30 years has had as its objective the detection of relatively gross effects of any pollution from oil terminal operations at Sullom Voe. While no such effects have been detected, the surveys have provided time series spanning several decades of macrobenthic and rocky shore community structure, that are possibly unique in the UK. Significantly, these data have been gathered over a time period when, according to most reports, pronounced changes in climate have taken place.

The measured ecological changes have taken place against a meteorological and oceanographic background characterised by rising air and sea surface temperatures yet stable, or slightly declining, ocean salinities. The effect of rising sea temperatures is best illustrated by a dramatic increase in the abundance of warm-water plankton indicator species around Shetland after the mid-1980s. The last ca. 30 years have also been characterised by a marked change in the nature of the North Atlantic Oscillation (NAO) that has altered from a predominantly positive mode during the1980s and a period of increased storminess to a strongly negative mode during the last decade and reduced storminess.

The analyses of macrobenthic data provides evidence of long-term change in the benthic communities with a rate of change that has been irregular although with some evidence of greater community stability during the 1990s. The analysis of rocky shore data also provides evidence of long-term change in community structure with relatively large changes having taken place between 1993−94, 2000−01 and during 2005−06. The relationships between the observed changes in the macrobenthic and rocky shore communities and the oceanographic and meteorological parameters remains unclear.