Solar radiation partitioning within and immediately below the 21st century Arctic sea ice cover: A synthesis of models and observations of a brighter, warmer ocean
Abstract
One of the most prevalent aspects of large-scale Arctic sea-ice loss has been the pronounced summer retreat in the Chukchi and Beaufort seas. The causes of this sea-ice loss involve complex interactions between the atmosphere, ocean, and ice cover. Although theseinteractions are not fully understood, it has been shown that sunlight absorbed by the ocean drives enhanced sea-ice melt and heat storage. The modern ice cover is thinner and younger, has less snow, and possibly greater melt pond coverage. Each of these factors enhances the transmittance of sunlight through the ice cover into the ocean. Building on previous works, we propose to advance understanding of the thermodynamics of the sea ice cover and the water column immediately below the ice through investigations of: 1) the large-scale transmission of sunlight through a realistic ice cover, 2) the fate of this sunlight as it is transported into the water column, 3) seasonal evolution of these process. To address these problems, the effects of snow, melt ponds, and ice thickness variation on meter to multi-kilometer scales must be addressed. The goal of this effort is to examine the spatial variability and temporal evolution of solar partitioning and solar heating within the ice-ocean system to develop a quantitative understanding of heat inthe ocean beneath the modern ice cover. Addressing six questions is key to achieving this goal: (1) what are the spatial distribution and temporal evolution of the spectral light field beneath the summer ice cover in the Chukchi and Beaufort Seas? (2) What is thehorizontal and vertical distribution of absorbed solar heat in the ice-ocean system? (3) What happens to the absorbed solar heat: how is it partitioned between storage in the ocean, ice bottom ablation, and ice floe lateral melt? (4) What is the potential contribution of solar heat to the development of near surface temperature maxima, and how does the heat influence the timing and magnitude of this layer? (5) How does meltwater production at the surface, including formation and growth of melt ponds, modulate the timing, magnitude, and distribution of solar heat absorption beneath the ice? (6) What is the role of absorbed and penetrating solar radiation in the overall thermodynamics of the ice cover and the water column immediately below the ice? These questions will be addressed by resolving and analyzing the distribution of melt ponds, sea ice, and leads to quantify solar partitioning and solar heating within the ice-ocean system. The work will entail synthesis and analysis of existing remote sensing data, reanalysis products, autonomousice-tethered instrument platforms, radiative transfer models, and field observations from meter to multi-kilometer scales. The end-result of the project will be a quantitative understanding of the spatial distribution of reflected, absorbed, and transmitted spectral light fields, along with estimates of the vertical distribution of absorbed heat in the Beaufort and Chukchi Seas.Data and metadata from this study will be archived using Findability, Accessibility, Interoperability, and Reusability (FAIR) principles and made available to the research and broader communities. Specific deliverables include archived datasets of solar partitioning, maps of solar heat input trends and component contributions, optical parameters for model applications, peer-reviewed publications, and open-access code for provisioning the future of the published results.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- May 15, 2023
- Source ID
- N000142312484
Entities
People
- Bonnie Light
Organizations
- Office of Naval Research
- United States Navy
- University of Washington