This dataset consists of fatty acid analysis and compound specific stable isotope analysis of fatty acids (δ13C-FA). These parameters were measured in particulate organic matter (POM). POM was collected from sea ice cores (iPOM) and from open water phytoplankton (pPOM). Samples were collected on the R/V Polarstern PS106/1 (23 May - 21 June 2017) and PS106/2 (23 June - 20 July 2017) campaigns. See parameter list for different types of collection methods. POM was collected during PS106/1 over the Yermack Plateau, and during PS106/2 in the Barents Sea and in the Nansen Basin (Arctic Ocean). Extracted lipids were converted into fatty acid methyl esters, and quantified (via an internal standard) using an Agilent 6890N gas chromatograph. Compound specific stable isotope ratios of fatty acid methyl esters (δ13C-FA) were analyzed using a Trace Ultra gas chromatograph (GC), a GC Isolink system, and a Delta V Plus isotope ratios mass spectrometer, connected to a Conflo IV interface. The purpose of these measurements was to determine differences in carbon (energetic) sources in ice algae and phytoplankton. While all available fatty acids and their compound specific stable isotope values from POM are published in this dataset, we also focused on four trophic biomarker fatty acids (further outlined in our related publication).

Comments on ice core samples: Particulate organic matter within sea ice (iPOM) was collected by taking ice cores with a 9 cm inner diameter ice corer (Kovacs Enterprises, Mark II). The bottom 5 cm of each ice core was cut off, and then fatty acid and compound specific isotope analysis was gathered from these bottom 5 cm. Remark: The given date/time, latitude and longitude in the data table refers to the start of the ice station. During each ice station, several ice cores were sampled. Information on the exact position and time of sampling is not available.