Since my last blog entry, we have moved forward with running water column samples for nitrate concentration as well as running persulfate oxidation of total dissolved nitrogen (TDN) to nitrate. We oxidize TDN to nitrate by pipeting a sample into a glass test tube and adding a persulfate oxidizing reagent (made up of sodium hydroxide and potassium persulfate). Next we autoclave the prepared samples with reagent for 55 minutes. After the samples have cooled, the nitrogen concentration of the samples are then measured using a chemiluminescent analyzer.
Additionally, I have been spending many hours learning ocean data view (ODV), which is a free data visualization program that you can use to plot oceanographic data sets, including publicly available data sets such as World Ocean Atlas. The software allows users to create maps, cross-sections and nutrient profiles. ODV even allows the users to create their own variables relevant to their specific research. It is an invaluable resource for chemical oceanographers or anyone studying ocean chemistry.