The data sets under this data collection include detailed snow pit studies of snow temperature, density, specific surface area (SSA), stratigraphy (snow grain type & size and hand hardness), and salinity as well as high-resolution snow penetrometer measurement profiles. The data were collected during the ALERT2018 campaign (Multidisciplinary Arctic Program (MAP) - Last Ice) off Alert, Nunavut, Canada in the Lincoln Sea in May 2018. For more detailed information, please refer to the individual data sets.