Assessing the Multi-Scale Surface Albedo Responses to Blowing Snow in East Antarctica Using Coordinated Ground and Satellite Observations

Surface albedo is crucial for the polar energy balance. Blowing snow (BLSN) frequently perturbs coastal Antarctic albedo, yet its specific radiative effects and observability by medium-resolution satellites remain poorly understood. This study combines multi-source ground observations at Zhongshan Station with Sentinel-2 and MODIS imagery to evaluate the multi-scale albedo response to BLSN. The results show that when snowfall and BLSN occur simultaneously, they generally lead to spatially uniform surface brightening. Conversely, when BLSN occurs after snowfall has ended, strong winds drive snow erosion and redistribution, producing highly dispersed, interleaved patches of local positive and negative albedo changes. Scale-bridging analysis reveals that spatially uniform brightening is reliably captured by medium-resolution satellites. However, these highly dispersed local signals extensively cancel each other out during spatial averaging. In the evaluated events, this cancellation drives the net regional signal toward zero, masking a substantial local surface shortwave radiative forcing that, at solar noon, can reach tens to over a hundred W m−2. This study suggests that the observability of dynamic surface perturbations depends on their sub-pixel spatial structure. Consequently, a near-zero signal at medium resolutions does not guarantee an unchanged surface, highlighting a hidden cancellation effect that obscures critical local energy redistributions.