AMT25 (JR15001) micro-molar nutrient measurements from CTD bottle samples.

(1) Plymouth Marine Laboratory; (2) University of Liverpool Department of Earth, Ocean and Ecological Sciences

This dataset consists of 1148 measurements of micromolar nutrient concentrations made on samples collected during the Atlantic Meridional Transect programme cruise 25 (AMT25 JR15001) between 18th September and 2nd November 2015. The cruise track between UK and Chile passed through both north and south Atlantic gyres. This dataset contributes to the AMT time-series of core oceanographic measurements along a north-south transect of the Atlantic Ocean. Samples were collected on a daily basis at 10 to 18 depths, usually in the upper 500m but up to 5000m, using a CTD rosette with 24 x 20 L OTE (Ocean Test Equipment) bottles. Samples were analysed within 3-4 hours of collection for nitrate+nitrite, nitrite, phosphate and silicate using a 5-channel Bran and Luebbe AAIII segmented flow, colourimetric, auto-analyser (Brewer and Riley (1965) for nitrate, Grasshoff (1976) for nitrite, Kirkwood (1989) and Mantoura and Woodward (1983) for phosphate and silicate). Established, proven analytical protocols were used.