Avelina, Raquel; da Cunha, Leticia Cotrim; Kerr, Rodrigo; Farias, Cássia de O; Hamacher, Claudia; Mata, Mauricio M: Dissolved organic carbon along the northern Antarctic Peninsula during Almirante Maximiano cruises NAUTILUS (2015-2019) [dataset]. PANGAEA, https://doi.pangaea.de/10.1594/PANGAEA.971679 (dataset in review)

Here we provide data on dissolved organic carbon (DOC in µmol kg–1), temperature (ºC), and practical salinity measured along the northern Antarctic Peninsula (NAP) in five consecutive austral summers between 2015 and 2019 obtained during the NAUTILUS project under the umbrella of the Brazilian High Latitude Oceanography Group (GOAL; http://goal.furg.br/). The oceanographic cruises of NAUTILUS project were carried out on board the Brazilian Navy RV NPo Almirante Maximiano. This study revisited the datasets for the Gerlache Strait (da Cunha et al., 2018) and Bransfield Strait (Avelina et al., 2020) obtained between February 2015 and 2016 and presents results sampled by GOAL in February 2015 and 2016 in the southernmost Drake Passage and the Bellingshausen and Weddell Seas as well as the dataset from the Gerlache Strait collected in February 2017-2018 and January 2019 (Avelina et al. in prep.). The CTD-Rosette set from Sea Bird Electronics® Inc. (SBE) model SBE 911plus was used to measure the hydrographic parameters in the water column. The accuracy of the temperature and salinity sensors used corresponds to ± 0.001 °C and ± 0.003, respectively (Dotto et al., 2021). DOC sampling and analysis carried out during the NAUTILUS oceanographic cruises followed the same method described in da Cunha et al. (2018) and Avelina et al. (2020) for the Gerlache and Bransfield Straits, respectively. All the DOC samples from the NAUTILUS cruises were analyzed at the Marine Organic Geochemistry and Chemical Oceanography Laboratories of the Rio de Janeiro State University (UERJ). Briefly, during NAUTILUS cruises (Avelina et al., 2020; da Cunha et al., 2018) we carried out filtration of seawater samples, collected in the upper mixed layer, to separate the particulate and dissolved organic carbon and deep samples were not filtered (Dickson et al., 2007). The samples were kept frozen until they were analyzed in the respective laboratories. The DOC samples were analyzed using a Shimadzu TOC L® Series analyzer, as non-purgeable organic carbon, in high-temperature catalytic combustion (Dickson et al., 2007). In addition, all samples were subjected to between three and five replicate injections (acceptable coefficient of variation < 1%). The carbon analyzers were standardized with solutions of potassium hydrogen phthalate (KHP) in Milli-Q® water. The instrument blank was checked by measuring the DOC in Milli-Q® water with a low carbon content (DOC < 8 μmol kg–1).