Expedition Bykovsky Peninsula 2017 Degradation of sub-aquatic permafrost can, impact offshore infrastructure, affect coastal erosion and release large quantities of methane, which may reach the atmosphere [...] injections into the sediment. The relative importance of these controls on the rate of sub-aquatic permafrost degradation, however, remains poorly understood. Therefore, the overarching science goal for the [...] the 2017 Bykovsky Spring Expedition was to evaluate the nature and distribution of subaquatic permafrost and taliks in multiple cryostratigraphic settings with drilling, sampling, near-surface geophysics