RRS Discovery Cruise 365, 11 May-02 Jun 2011. The Extended Ellett Line 2011

The Extended Ellett Line is a full-depth hydrographic section between Iceland, 60°N 20°W, Rockall and Scotland. The original Ellett Line across the Rockall Trough was first occupied in 1975 when measurements were attempted four times a year. In 1996 the line was extended to Iceland and since then has been occupied approximately annually. The data form a 35 year time series of the oceanic conditions west of the British Isles. The section monitors the characteristics of the warm water inflow into the Nordic Seas and thence to the Arctic, and observes part of the returning cold water outflow with easurements of the Iceland-Scotland Overflow and the overflow of the Wyville-Thomson Ridge into the Rockall Trough. The 2011 occupation, RRS Discovery cruise 365, was curtailed by both technical problems and bad weather. 45 of the 48 CTD stations were worked between the Iceland and Scotland shelf edges. Line G, part of the SAMS observation network of the Scottish continental shelf was partially completed, with 4 stations at the western end not worked. Samples were taken for CFC and SF6 analysis, DIC and alkalinity, inorganic nutrients, aluminium, POC, bacterial abundance and biomass, and for phytoplankton community structure. Plans to repeat stations, to collect validation data for the SAMS glider and to investigate eddies in the Rockall Trough had to be abandoned.