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Polar oceans and sea ice cover 15% of the Earth’s ocean surface, and the environment is changing rapidly at both poles. Improving knowledge on the interactions between the atmospheric and oceanic realms in the polar regions, a Surface Ocean–Lower Atmosphere Study (SOLAS) project key focus, is essential to understanding the Earth system in the context of climate change. However, our ability to monitor the pace and magnitude of changes in the polar regions and evaluate their impacts for the rest of the globe is limited by both remoteness and sea-ice coverage. Sea ice not only supports biological activity and mediates gas and aerosol exchange but can also hinder some in-situ and remote sensing observations. While satellite remote sensing provides the baseline climate record for sea-ice properties and extent, these techniques cannot provide key variables within and below sea ice. Recent robotics, modeling, and in-situ measurement advances have opened new possibilities for understanding the ocean–sea ice–atmosphere system, but critical knowledge gaps remain. Seasonal and long-term observations are clearly lacking across all variables and phases. Observational and modeling efforts across the sea-ice, ocean, and atmospheric domains must be better linked to achieve a system-level understanding of polar ocean and sea-ice environments. As polar oceans are warming and sea ice is becoming thinner and more ephemeral than before, dramatic changes over a suite of physicochemical and biogeochemical processes are expected, if not already underway. These changes in sea-ice and ocean conditions will affect atmospheric processes by modifying the production of aerosols, aerosol precursors, reactive halogens and oxidants, and the exchange of greenhouse gases. Quantifying which processes will be enhanced or reduced by climate change calls for tailored monitoring programs for high-latitude ocean environments. Open questions in this coupled system will be best resolved by leveraging ongoing international and multidisciplinary programs, such as efforts led by SOLAS, to link research across the ocean–sea ice–atmosphere interface.
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Applying Understanding of Earth Systems, Including Climate Change, to Exploration of Other Ocean Worlds
Earth’s polar and deep ocean systems and how they are affected by environmental changes provide analogs for understanding key processes acting in other ocean worlds, from physical and geological dynamics to chemical and biological processes. Subglacial lakes in Antarctica that are overlain by multiple kilometers of ice, as well as polar ice shelves underlain by subsurface areas of the ocean, are key sites for studying processes operating at ice-water and rock-ocean interfaces on Earth and on icy worlds. Hydrothermal vents at the seafloor release chemicals that provide energy for life and are also key areas for cross-linked Earth and planetary studies relevant to deep oceans dynamics. The presence of chemosynthetic microbes that are then consumed by multicellular life forms provide an analog for examining the potential existence of life in some subregions within ocean worlds. Here, we discuss the various Earth system processes that may have analogs on other ocean worlds and the benefits of collaborative Earth and planetary science investigations.
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- Award ID(s):
- 1917469
- PAR ID:
- 10431272
- Date Published:
- Journal Name:
- Oceanography
- ISSN:
- 1042-8275
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.5670/oceanog.2021.413
