@article {josey_clearer_2023,
	title = {A clearer view of Southern Ocean air{\textendash}sea interaction using surface heat flux asymmetry},
	journal = {Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences},
	volume = {381},
	number = {2249},
	year = {2023},
	note = {Publisher: Royal Society},
	month = {may},
	pages = {20220067},
	abstract = {Progress in understanding Southern Ocean heat exchange and wind forcing is discussed and new results presented. These include a metric of the zonal asymmetry between surface ocean heat gain in the Atlantic/Indian sector and heat loss in the Pacific sector. The asymmetry arises from an intersector variation in the humidity gradient between the sea surface and near-surface atmosphere. This gradient increases by 60\% in the Pacific sector enabling a 20 Wm-2 stronger latent heat loss compared with the Atlantic/Indian sector. The new metric is used for intercomparison of atmospheric reanalyses and CMIP6 climate simulations. CMIP6 has weaker Atlantic/Indian sector heat gain compared with the reanalyses primarily due to Indian Ocean sector differences. The potential for surface flux buoys to provide an observation-based counterpart to the asymmetry metric is explored. Over the past decade, flux buoys have been deployed at two sites (south of Tasmania and upstream of Drake Passage). The data record provided by these moorings is assessed and an argument developed for a third buoy to sample the Atlantic/Indian sector of the asymmetry metric. To close, we assess evidence that the main westerly wind belt has strengthened and moved southward in recent decades using the ERA5 reanalysis. This article is part of a discussion meeting issue {\textquoteright}Heat and carbon uptake in the Southern Ocean: the state of the art and future priorities{\textquoteright}.},
	keywords = {air{\textendash}sea heat flux, Southern Ocean, wind stress},
	doi = {10.1098/rsta.2022.0067},
	url = {https://royalsocietypublishing.org/doi/full/10.1098/rsta.2022.0067},
	author = {Josey, Simon A. and Grist, Jeremy P. and Mecking, Jennifer V. and Moat, Ben I. and Schulz, Eric}
}
@article {meijers_finale_2023,
	title = {Finale: impact of the ORCHESTRA/ENCORE programmes on Southern Ocean heat and carbon understanding},
	journal = {Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences},
	volume = {381},
	number = {2249},
	year = {2023},
	note = {Publisher: Royal Society},
	month = {may},
	pages = {20220070},
	abstract = {The 5-year Ocean Regulation of Climate by Heat and Carbon Sequestration and Transports (ORCHESTRA) programme and its 1-year extension ENCORE (ENCORE is the National Capability ORCHESTRA Extension) was an approximately 11-million-pound programme involving seven UK research centres that finished in March 2022. The project sought to radically improve our ability to measure, understand and predict the exchange, storage and export of heat and carbon by the Southern Ocean. It achieved this through a series of milestone observational campaigns in combination with model development and analysis. Twelve cruises in the Weddell Sea and South Atlantic were undertaken, along with mooring, glider and profiler deployments and aircraft missions, all contributing to measurements of internal ocean and air{\textendash}sea heat and carbon fluxes. Numerous forward and adjoint numerical experiments were developed and supported by the analysis of coupled climate models. The programme has resulted in over 100 peer-reviewed publications to date as well as significant impacts on climate assessments and policy and science coordination groups. Here, we summarize the research highlights of the programme and assess the progress achieved by ORCHESTRA/ENCORE and the questions it raises for the future. This article is part of a discussion meeting issue {\textquoteleft}Heat and carbon uptake in the Southern Ocean: the state of the art and future priorities{\textquoteright}.},
	keywords = {climate, ocean carbon, ocean circulation, ocean heat, ocean{\textendash}atmosphere fluxes, Southern Ocean},
	doi = {10.1098/rsta.2022.0070},
	url = {https://royalsocietypublishing.org/doi/full/10.1098/rsta.2022.0070},
	author = {Meijers, Andrew J. S. and Meredith, Michael P. and Shuckburgh, Emily F. and Kent, Elizabeth C. and Munday, David R. and Firing, Yvonne L. and King, Brian and Smyth, Tim J. and Leng, Melanie J. and George Nurser, A. J. and Hewitt, Helene T. and Povl Abrahamsen, E. and Weiss, Alexandra and Yang, Mingxi and Bell, Thomas G. and Alexander Brearley, J. and Boland, Emma J. D. and Jones, Daniel C. and Josey, Simon A. and Owen, Robyn P. and Grist, Jeremy P. and Blaker, Adam T. and Biri, Stavroula and Yelland, Margaret J. and Pimm, Ciara and Zhou, Shenjie and Harle, James and Cornes, Richard C.}
}
@article {RN153,
	title = {Mooring Observations of Air-Sea Heat Fluxes in Two Subantarctic Mode Water Formation Regions},
	journal = {Journal of Climate},
	volume = {33},
	number = {7},
	year = {2020},
	pages = {2757-2777},
	type = {Journal Article},
	abstract = {Wintertime surface ocean heat loss is the key process driving the formation of Subantarctic Mode Water (SAMW), but there are few direct observations of heat fluxes, particularly during winter. The Ocean Observatories Initiative (OOI) Southern Ocean mooring in the southeast Pacific Ocean and the Southern Ocean Flux Station (SOFS) in the southeast Indian Ocean provide the first concurrent, multiyear time series of air{\textendash}sea fluxes in the Southern Ocean from two key SAMW formation regions. In this work we compare drivers of wintertime heat loss and SAMW formation by comparing air{\textendash}sea fluxes and mixed layers at these two mooring locations. A gridded Argo product and the ERA5 reanalysis product provide temporal and spatial context for the mooring observations. Turbulent ocean heat loss is on average 1.5 times larger in the southeast Indian (SOFS) than in the southeast Pacific (OOI), with stronger extreme heat flux events in the southeast Indian leading to larger cumulative winter ocean heat loss. Turbulent heat loss events in the southeast Indian (SOFS) occur in two atmospheric regimes (cold air from the south or dry air circulating via the north), while heat loss events in the southeast Pacific (OOI) occur in a single atmospheric regime (cold air from the south). On interannual time scales, wintertime anomalies in net heat flux and mixed layer depth (MLD) are often correlated at the two sites, particularly when wintertime MLDs are anomalously deep. This relationship is part of a larger basin-scale zonal dipole in heat flux and MLD anomalies present in both the Indian and Pacific basins, associated with anomalous meridional atmospheric circulation.},
	keywords = {Atmosphere-ocean interaction, Buoy observations, Heat budgets/fluxes, Oceanic mixed layer, Southern Ocean, Water masses/storage},
	issn = {0894-8755},
	doi = {10.1175/JCLI-D-19-0653.1},
	author = {Tamsitt, V. and Cerovecki, I. and Josey, S. A. and Gille, S. T. and Schulz, E.}
}
@article {RN188,
	title = {Optimizing Mooring Placement to Constrain Southern Ocean Air-Sea Fluxes},
	journal = {Journal of Atmospheric and Oceanic Technology},
	volume = {37},
	number = {8},
	year = {2020},
	pages = {1365-1385},
	type = {Journal Article},
	abstract = {Proposals from multiple nations to deploy air{\textendash}sea flux moorings in the Southern Ocean have raised the question of how to optimize the placement of these moorings in order to maximize their utility, both as contributors to the network of observations assimilated in numerical weather prediction and also as a means to study a broad range of processes driving air{\textendash}sea fluxes. This study, developed as a contribution to the Southern Ocean Observing System (SOOS), proposes criteria that can be used to determine mooring siting to obtain best estimates of net air{\textendash}sea heat flux (Qnet). Flux moorings are envisioned as one component of a multiplatform observing system, providing valuable in situ point time series measurements to be used alongside satellite data and observations from autonomous platforms and ships. Assimilating models (e.g., numerical weather prediction and reanalysis products) then offer the ability to synthesize the observing system and map properties between observations. This paper develops a framework for designing mooring array configurations to maximize the independence and utility of observations. As a test case, within the meridional band from 35{\textdegree} to 65{\textdegree}S we select eight mooring sites optimized to explain the largest fraction of the total variance (and thus to ensure the least variance of residual components) in the area south of 20{\textdegree}S. Results yield different optimal mooring sites for low-frequency interannual heat fluxes compared with higher-frequency subseasonal fluxes. With eight moorings, we could explain a maximum of 24.6\% of high-frequency Qnet variability or 44.7\% of low-frequency Qnet variability.},
	keywords = {Buoy observations, In situ atmospheric observations, In situ oceanic observations, Southern Ocean},
	issn = {0739-0572},
	doi = {10.1175/JTECH-D-19-0203.1},
	author = {Wei, Y. Z. and Gille, S. T. and Mazloff, M. R. and Tamsitt, V. and Swart, S. and Chen, D. K. and Newman, L.}
}
@article {RN148,
	title = {Constraining Southern Ocean Air-Sea-Ice Fluxes Through Enhanced Observations},
	journal = {Frontiers in Marine Science},
	volume = {6},
	year = {2019},
	pages = {421},
	type = {Journal Article},
	abstract = {Air-sea and air-sea-ice fluxes in the Southern Ocean play a critical role in global climate through their impact on the overturning circulation and oceanic heat and carbon uptake. The challenging conditions in the Southern Ocean have led to sparse spatial and temporal coverage of observations. This has led to a {\textquotedblleft}knowledge gap{\textquotedblright} that increases uncertainty in atmosphere and ocean dynamics and boundary-layer thermodynamic processes, impeding improvements in weather and climate models. Improvements will require both process-based research to understand the mechanisms governing air-sea exchange and a significant expansion of the observing system. This will improve flux parameterizations and reduce uncertainty associated with bulk formulae and satellite observations. Improved estimates spanning the full Southern Ocean will need to take advantage of ships, surface moorings, and the growing capabilities of autonomous platforms with robust and miniaturized sensors. A key challenge is to identify observing system sampling requirements. This requires models, Observing System Simulation Experiments (OSSEs), and assessments of the specific spatial-temporal accuracy and resolution required for priority science and assessment of observational uncertainties of the mean state and direct flux measurements. Year-round, high-quality, quasi-continuous in situ flux measurements and observations of extreme events are needed to validate, improve and characterize uncertainties in blended reanalysis products and satellite data as well as to improve parameterizations. Building a robust observing system will require community consensus on observational methodologies, observational priorities, and effective strategies for data management and discovery.},
	keywords = {air-sea/air-sea-ice fluxes, climate, ocean{\textendash}atmosphere interaction, ocean{\textendash}ice interaction, Southern Ocean},
	issn = {2296-7745},
	doi = {10.3389/fmars.2019.00421},
	url = {https://www.frontiersin.org/article/10.3389/fmars.2019.00421},
	author = {Swart, Sebastiaan and Gille, Sarah T. and Delille, Bruno and Josey, Simon and Mazloff, Matthew and Newman, Louise and Thompson, Andrew F. and Thomson, Jim and Ward, Brian and du Plessis, Marcel D. and Kent, Elizabeth C. and Girton, James and Gregor, Luke and Heil, Petra and Hyder, Patrick and Pezzi, Luciano Ponzi and de Souza, Ronald Buss and Tamsitt, Veronica and Weller, Robert A. and Zappa, Christopher J.}
}
