Winter atmospheric boundary layer observations over sea ice in the coastal zone of the Bay of Bothnia (Baltic Sea)

摘要: Abstract. The Hailuoto Atmospheric Observations over Sea ice (HAOS) campaign took place at the westernmost point of island (Finland) between 27 February and 2 March 2020. aim was to obtain atmospheric boundary layer (ABL) observations seasonal sea in Bay Bothnia. Throughout 4  d , both fixed-wing and quad-propeller rotorcraft unmanned aerial vehicles (UAVs) were deployed measure properties the lower ABL accompanying high-resolution aerial photographs the underlying surface. Additionally, a 3D sonic anemometer, an automatic weather station, Halo Doppler lidar installed on shore to collect meteorological observations. During UAV flights, measurements of temperature, relative humidity, pressure collected at four different altitudes 25 100  m area of ∼  1.5  km2 ice, located 1.1–1.3  km off Hailuoto's Marjaniemi pier, together with orthomosaic maps ice surface below. Altogether obtained dataset consists 27 meteorological flights, photogrammetry missions, continuous atmospheric properties from ground-based stations coast. acquired observations have been quality controlled post-processed are available through PANGAEA repository ( https://doi.org/10.1594/PANGAEA.918823 Wenta et al. ,  2020 ). The provides us valuable information about thin, newly formed cover physical processes interface atmosphere which may be used for validation further improvement numerical weather prediction (NWP) models.