TCD Paper: Bioalbedo model and critique of empirical methods

Our new paper in The Cryosphere presents a model for predicting the spectral albedo reduction resulting from biological growth on snow or ice. The biomass concentration and pigmentation of cells, cell radii, vertical position of the cells in the snow or ice, ice grain radii and inorganic impurity optical properties, mass concentration and vertical distribution can all be prescribed by the user. The model can also be tailored to specific times and locations using measured or modelled incoming solar irradiance. Interstitial water can also be included to better model snow and ice in a state of melt.

We used the model to support a review of the techniques used to characterize bioalbedo in the field and examine some of the difficulties in linking empirical ground measurements with remote sensing and theoretical work. The paper is written specifically to support those new to spectroscopy in designing experiments to measure biological effects on albedo and to highlight areas of uncertainty.

Biological impurities contribute to the dark colouration of the ice surface at the Black and Bloom camp in 2016

Aerial view of our field site – the dark appearance is due in part to the absorption of visible light by algae

The paper is available to view here.