The distribution of solar energy under ponded sea ice
Abstract
The effects of the Arctic's thinning sea ice cover are felt throughout the Earth system, from chemistry and biology to lower-latitude weather and climate. The thinner, first-year sea ice that accounts for most of the summertime sea ice cover is itself covered by melt ponds, whose albedo is lower than bare ice, and who have a complex and variable spatial distribution. We show that the coupled interaction between sea ice, solar radiation, and the Arctic ocean is strongly influenced by the shape and fractal dimension of melt ponds that form in summer, in addition to their area. We investigate the three-dimensional light field under ponded sea ice and thus a previously unexplored control on the coupled system, finding that solar energy at depth is determined by the fractal and phase separation properties of the ice/pond surface. We show that the aggregate properties of the sub-ice light field may be described fully in terms of a single parameter based on the pond surface geometry, and explore the influence of pond geometry on the ecological and thermodynamic sea ice processes that depend on solar radiation in a climate model study.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFM.C21D1377H
- Keywords:
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- 3307 Boundary layer processes;
- ATMOSPHERIC PROCESSESDE: 3349 Polar meteorology;
- ATMOSPHERIC PROCESSESDE: 0750 Sea ice;
- CRYOSPHEREDE: 4540 Ice mechanics and air/sea/ice exchange processes;
- OCEANOGRAPHY: PHYSICAL