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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Surface ocean-lower atmospheric processes in the Indian Ocean: Current understanding, knowledge gaps, and future directions
Our understanding of surface ocean and lower atmosphere processes in the Indian Ocean (IO) region shows significant knowledge gaps mainly due to the paucity of observational studies. The IO basin is bordered by landmasses and an archipelago on 3 sides with more than one-quarter of the global population dwelling along these coastal regions. Therefore, interactions between dynamical and biogeochemical processes at the ocean–atmosphere interface and human activities are of particular importance here. Quantifying the impacts of changing oceanic and atmospheric processes on the marine biogeochemical cycle, atmospheric chemistry, ecosystems, and extreme events poses a great challenge. A comprehensive understanding of the links between major physical, chemical, and biogeochemical processes in this region is crucial for assessing and predicting local changes and large-scale impacts. The IO is one of the SOLAS (Surface Ocean-Lower Atmosphere Study) cross-cutting themes as summarized in its implementation strategy. This article attempts to compile new scientific results over the past decade focusing on SOLAS relevant processes within the IO. Key findings with respect to monsoon and air–sea interactions, oxygen minimum zones, ocean biogeochemistry, atmospheric composition, upper ocean ecosystem, and interactions between these components are discussed. Relevant knowledge gaps are highlighted, with a goal to assist the development of future IO research programs. Furthermore, we provided several recommendations to conduct interdisciplinary research to advance our understanding on the land–ocean–atmospheric interaction in the IO.
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- Award ID(s):
- 1840868
- PAR ID:
- 10558060
- Publisher / Repository:
- University of California Press
- Date Published:
- Journal Name:
- Elem Sci Anth
- Volume:
- 12
- Issue:
- 1
- ISSN:
- 2325-1026
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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