A series of Tpop bottom temperature sensors manufactured by the University of Rhode Island (contact: Randolph Watts ) were deployed during leg 4 of MOSAiC, around Yermark Plateau and Fram Strait, from June 2020 to August 2020. They recorded the temperature at approximately 10 m above the seafloor with an hourly resolution from their deployment till they surfaced automatically on 1 September 2021. They are provided here calibrated against the MOSAiC ship CTD (Tippenhauer et al., 2023, DOI:10.1594/PANGAEA.959963).