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Abstract

The University of Alaska Fairbanks Hyperspectral Imaging Laboratory (HyLab) provides field observations, acquisition, and processing of airborne hyperspectral remote sensing. We present preliminary results from hyperspectral surveys of Mendenhall glacier in Southeast Alaska, Grewingk glacier in Kachemak Bay, and snow covered areas across the Bonanza Creek Experimental Forest Creek Research Watershed in Interior Alaska. We aim to discuss the potential of hyperspectral imagery for different aspects of cryospheric monitoring in general, and for glacier ice albedo retrieval in particular. Ice albedo at the glacier surface can vary strongly at small spatial scales due to, e.g., the presence of liquid water or light absorbing particles. This variability is not fully captured by satellite data due to lacking resolution. While subgrid variability can be assessed by comparing in situ spectroradiometric measurements with satellite albedo products, a scale gap remains. Airborne hyperspectral imagery with high spatial and spectral resolution can help bridge this gap and contribute to our understanding of the driving processes behind local albedo variability. High resolution hyperspectral imagery further allows a more detailed assessment of how spatial and spectral resolution affects comparisons with satellite data and uncertainty in satellite derived albedo products. Fully leveraging the potential of hyperspectral imagery for change detection and monitoring of the cryosphere requires targeted survey campaigns and optimized data processing schemes, as well as - ideally - time synchronous in situ data. We are seeking exchange with the scientific community on how to best meet these challenges and identify data needs across cryospheric disciplines.