Blowing Snow at McMurdo Station, Antarctica During the AWARE Field Campaign: Surface and Ceilometer Observations

Blowing snow (BLSN) is an impactful process in cold climates, affecting regional thermodynamics, radiation properties, and the surface mass balance of snow. Though it has significant climatic impacts, the process is still poorly understood and not widely included in weather and climate models. In 2016, the AWARE Field Campaign saw the deployment of a large suite of in situ and remote sensing instruments to McMurdo Station, Antarctica allowing for investigation of BLSN. A ceilometer‐based BLSN detection algorithm used elsewhere in Antarctica is applied to data from AWARE, yielding a BLSN frequency of 14.1% compared to 8.2% as detected by human observers. To increase confidence in detections, the algorithm is updated to have shorter temporal averaging and to include a variety of meteorological thresholds to limit false detections due to fog. Efforts to incorporate a laser disdrometer into the algorithm were unsuccessful. An unphysical dependence of particle size distributions on wind speed is found suggesting observations are problematic at wind speeds greater than 10 m s−1. The revised algorithm detected a BLSN frequency of 7.4%, increasing agreement with human observations and confidence that the process is actively occurring at the observation site. These observations are put into context of a climatology of human observations of BLSN at McMurdo station from 2002–2018. An annual average of 8.0%–14.0% is estimated, with a total annual range of 3.4%–21.3%. Regardless of whether BLSN is observed by humans or instrument, the majority of cases at this location are associated with ongoing precipitation. Plain Language Summary This study investigated the occurrence of blowing snow (BLSN) at McMurdo Station in Antarctica. Understanding this process is important for reasons ranging from immediate travel impacts (e.g., whiteout conditions) to long‐term changes in ice sheet surface mass balance. We used a number of meteorological instruments and human observations to estimate how often BLSN occurs. We provide a range in BLSN frequencies because we don't know what ground truth is. The instrument we hoped would provide this information struggles during periods of strong winds. Because BLSN is associated with strong winds, this is problematic. Key Points The frequency of blowing snow at McMurdo Station, Antarctica is analyzed based on human observations and ground‐based instrumentation Alterations to the algorithm developed by Gossart et al. (2017) are presented to inc