Using the International Comprehensive Ocean-Atmosphere Data Set (ICOADS) to measure sea surface temperature in West Scottish sea-lochs.

Understanding how environmental variables such as Sea Surface Temperatures (SST) affect biological primary production within Western Scottish sea-lochs (fjords) is important for fishing and tourism. A multiyear SST time-series has been lacking for sites in the Firth of Lorn. This report compares an ICOADS (International Comprehensive Ocean-Atmosphere Data Set), starting 1970, with observations of SST within sea lochs of this Firth. Two datasets were compiled and used to provide monthly SST data from sea-lochs: one from a temperature recorder deployed at 10 m depth since the mid-1990s; and the other from CTD observations made during inshore research cruises. The ICOADS was well but not perfectly correlated with other two datasets (r2 0.86 to 0.90), and showed a greater annual range in temperature than the inshore data. Nevertheless, it can, with corrections, be used as a proxy for inshore SST.