The dataset comprises high-resolution (1-min) measurements of dissolved nitrous oxide in surface waters of the Eastern Tropical Indian Ocean. The observations were conducted during the expedition SO-305 on board R/V SONNE (April-May 2024). Seawater was drawn on board by means of a submersible pump installed at 6 m depth, and measurements of equilibrated headspace were carried out as described in Arévalo-Martínez et al. (2013): https://doi.org/10.5194/os-9-1071-2013.

OA-ICOS Analyzer coupled to shower head equilibrator as in Arévalo-Martínez et al. (2013): https://doi.org/10.5194/os-9-1071-2013. Equilibration temperature measured with a FLUKE 1524 reference thermometer (+/-0.01°C). Sea surface temperature and salinity derived from discrete in-situ measurements with a Seabird SBE45 (Temperature: +/-0.002°C; Conductivity: ± 0.0003 S/m). The gaps in equilibration temperature caused by logger malfunction were filled based on the linear correlation with SST (equ_temp_calc=0.9627*SST + 1.002).