Indirect effects and feedbacks associated with light-absorbing constituents in the cryosphere

Abstract:

Light-absorbing constituents in snow and ice directly enhance melt by increasing solar absorption. These impacts are quantifiable through traditional IPCC metrics such as instantaneous direct radiative forcing. Less well-understood and quantifiable are indirect effects and feedbacks associated with the presence of these constituents. Such mechanisms range from global-scale albedo feedback, which enhances the efficacy of radiative forcing from light-absorbing constituents in the cryosphere, to microphysical mechanisms involving the optics of snow and biology of algae. This presentation will explore such effects and briefly assess our current level of understanding of them.