Nitrite (NO2) concentrations from multiple HOE-DYLAN cruises from July to September 2012 (C-MORE project)

Seawater samples were collected from Niskin bottles with acid-washed syringes to avoid ammonium contamination from air and ship fumes. Samples were kept frozen (-20 ºC) until analysis. Nitrite was measured at the nanomolar level following Bendschneider and Robinson (1952) method, using a flow-injection system coupled to a 2m Liquid Waveguide Capillary Cell to read the color. Low nutrient seawater was used for working standards preparation, blanks and carrier. The absorbance-concentration relationship was linear up to at least 200 nM nitrite, with a method detection limit of 0.7 nM and an error of 1.5% at 50-100 nM and 2% at 150 nM.