Donald Slater, University of Edinburgh, Edinburgh, EH9, United Kingdom, Eleanor Johnstone, University of Edinburgh, Edinburgh, United Kingdom, Martim Mas e Braga, Stockholm University, Department of Physical Geography, Stockholm, Sweden, Neil Fraser, Scottish Association for Marine Science, Oban, United Kingdom, Tom R Cowton, University of St Andrews, School of Geography and Sustainable Development, St Andrews, United Kingdom and Mark E Inall, SAMS, Oban, United Kingdom