Atlantic Meridional Transect cruise AMT22 (JC079) micro-molar nutrient measurements from CTD bottle samples collected in 2012.

This dataset consists of measurements of micromolar nutrient concentrations made on samples collected during the Atlantic Meridional Transect programme cruise 22 (AMT22 JC079) on the RRS James Cook, between 10th October and 24th November 2012. The cruise track was between Southampton, UK and Punta Arenas, Chile, and 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 twice daily at all sampled CTDs (Total of 73) at selected depths in the upper 500m of the water column. A CTD rosette with 24 x 20L Niskin bottles was deployed. Samples were sub-sampled into acid-clean 60 ml HDPE (Nalgene) sample bottles. Analysis for nutrients was completed within 1-2 hours of sampling in all cases. Clean handling techniques were employed to avoid contamination of the samples. The analyses were for Nitrate+Nitrite, Nitrite, Phosphate, and Silicate. The main nutrient analyser was a 5-channel Bran and Luebbe AAIII segmented flow colorimetric autoanalyser. The analytical chemical methodologies used were according to Brewer and Riley (1965) for nitrate, Grasshoff (1976) for nitrite and Kirkwood (1989) for phosphate and silicate.