Abstract. In this study, we compare eight recently developed snow depth products over Arctic sea ice, which
use satellite observations, modeling, or a combination of satellite and modeling approaches. These
products are further compared against various ground-truth observations, including those from ice
mass balance observations and airborne measurements. Large mean snow depth discrepancies are
observed over the Atlantic and Canadian Arctic sectors. The differences between climatology and
the snow products early in winter could be in part a result of the delaying in Arctic ice
formation that reduces early snow accumulation, leading to shallower snowpacks at the start of
the freeze-up season. These differences persist through spring despite overall more winter snow
accumulation in the reanalysis-based products than in the climatologies. Among the products
evaluated, the University of Washington (UW) snow depth product produces the deepest spring
(March–April) snowpacks, while the snow product from the Danish Meteorological Institute (DMI)
provides the shallowest spring snow depths. Most snow products show significant correlation with
snow depths retrieved from Operational IceBridge (OIB) while correlations are quite low against
buoy measurements, with no correlation and very low variability from University of Bremen and DMI
products. Inconsistencies in reconstructed snow depth among the products, as well as differences
between these products and in situ and airborne observations, can be partially attributed to
differences in effective footprint and spatial–temporal coverage, as well as insufficient
observations for validation/bias adjustments. Our results highlight the need for more targeted
Arctic surveys over different spatial and temporal scales to allow for a more systematic
comparison and fusion of airborne, in situ and remote sensing observations.
Snow depth on Arctic sea ice derived from radar: In situ comparisons and time series analysis