Research expedition MSM44 took place from June 30th, 2016 (Nuuk, Greenland) to July 30th, 2016 (Nuuk, Greenland). CTD data for 17 stations with a total of 45 individual casts along the cruise track were recorded using a Sea & Sun Technology CTD90M (SN 979) down to depths of 500m. The CTD was equipped with the following sensors: Temperature sensor Pt100 model 1509 (Thermal Developments International), Conductivity sensor 7-pole platinum coated electrode cell in quartz glass (Sea & Sun Technology), Seapoint Chlorophyll Fluorometer (Seapoint), dissolved oxygen sensor (DO522M18, Clark type, OxyGuard) and single rod electrode ph sensor (AMT Analysenmesstechnik GmbH). The data files contain the data for temperature, salinity, density, dissolved oxygen concentration and chlorophyll a concentration; as raw data and processed and flagged according to the recommendations for real-time data processing of EuroGOOS and GTSPP, as well as the outlier detection method CoTeDe (https://github.com/castelao/CoTeDe). Biogeographic regions are determined according to Spalding et al. (2012). TEOS-10 unit conversions have been performed with the GSW Oceanographic Toolbox (McDougall and Barker, 2011).