http://swrc.ontoware.org/ontology#Article Chlorophyll a and macro-nutrient concentrations during the icebreaker Shirase cruise of the 58th Japanese Antarctic Research Expedition en Southern Ocean chlorophyll a macro-nutrients Chlorophyll a concentration is the most common indicator of phytoplankton biomass, basically regulated by macro-nutrients and light intensity. Therefore, long-term monitoring of these parameters provides fundamental information on ecosystem changes with climate change. As part of the monitoring programs of the Japanese Antarctic Research Expedition (JARE), water temperature, salinity, chlorophyll-a concentration, macro-nutrients (nitrate, nitrite, phosphate, and silicate), and photosynthetically active radiation at the sea surface have been measured onboard the icebreakers Shirase and Fuji by JARE-7 during the 1965/66 season and by JARE-14 during the 1972/73 season, respectively. This report presents the latest data collected during the Shirase cruise in the 2016/17 season. Polar Data Journal 4 97-120 2020-09 National Institute of Polar Research 2432-6771 http://dx.doi.org/10.17592/001.2020070701|Original Data Marine biology