Ammonium concentrations in surface seawater profiles in the Southern Ocean collected on board the R/V Akademik Tryoshnikov during the austral summer of 2016/2017 as part of the Antarctic Circumnavigation Expedition (ACE).

<strong>Dataset abstract</strong> Seawater samples were collected from the ship's underway system or from the surface niskin bottle from the CTD rosette. Some incidental samples were collected from the surface using a bucket from the side of the ship or a zodiac. The samples were collected every 6 hours from the underway and from every CTD cast as part of the Antarctic Circumnavigation Expedition (ACE) which took place in the Austral summer of 2016/2017. Ammonium is representative of the recycled nitrogen pool in the upper mixed layer where inputs include marine production and terrestrial runoff. Seawater samples were collected and frozen during the expedition and analysed post-cruise and quality controlled to produce this dataset, which presents ammonium concentration in surface seawater from the Southern Ocean. <strong>Dataset contents</strong> ace_ammonium_concentration_surface_seawater.csv file, data file, comma-separated values ace_ammonium_concentration_surface_seawater_chnage_log.txt, metadata, text data_file_header.txt, metadata, text README.txt, metadata, text <strong>Change log</strong> <strong>v1.1</strong> - Added detection limit to README.txt. Data points formatted to 2 decimal places. <strong>v1.0</strong> - Initial release of dataset