This WP aims to obtain the first full annual cycle time series of high-resolution air-sea flux observations of heat, momentum and carbon dioxide. Using these, we want to address the following specific goals:
- Estimate the magnitudes of heat, momentum and carbon fluxes exchanged across the sea surface at high-resolution, including obtaining the first estimates in autumn to winter, south of 60°S.
- Identify the key temporal and spatial scales of variability of new in situ air-sea flux observations and compare them to widely-used satellite-reanalysis flux products.
- Establish how air-sea fluxes are modulated by synoptic storms, ocean dynamics (mixed layer processes, fronts and eddies) and sea ice cover.
- Understand the role of surface fluxes (incl. transient storms) and surface sea state (wave-wind interaction) on driving upper ocean processes and stratification (links to WP2 and WP4)
- During winter, under the ice, the partial pressure of CO2 is relatively high. We assess the specific contribution to the total annual air-sea carbon flux (in particular, whether there is strong outgassing in spring).
- Determine whether the uptake of CO2 south of 60°S is really as low as suggested by some previous studies. The latter may be biased by lack of data and absence of full seasonal data.
- Provide estimates of dissipation over the depth of the mixed layer from direct measurements using the Air-Sea Interaction Profiler and relate it to the air-sea fluxes of momentum and CO2.
- Task 1.0: Scientific coordination [Co-Leads: S. Swart (UGOT) and M. Hoppema (AWI)]
- Task 1.1: Observe air-sea fluxes of heat, momentum and CO2, particularly in autumn and winter [Lead: S. Swart (UGOT); participants: M. Hoppema (AWI), B. Ward (NUIG), J. Boutin (SU), S. Josey (UKRI-NOC), P. Monteiro (CSIR)]
- Task 1.2: Assess key scales of variability for heat, momentum and carbon air-sea fluxes [Co-Leads: S. Swart (UGOT) and M. Hoppema (AWI); participants: J. Boutin (SU), S. Josey (UKRI-NOC), P. Monteiro (CSIR)]
- Task 1.3: Determine the uncertainties of satellite-reanalysis air-sea flux estimates of momentum and heat [Co-Leads: S. Swart (UGOT) and S. Josey (UKRI-NOC)]
- Task 1.4: Determine the role of the ice lid to the annual air-sea flux of CO2 [Lead: M. Hoppema (AWI); participants: J. Boutin (SU), P. Monteiro (CSIR)]
- Task 1.5: Estimate the contribution of the CO2 air-sea flux of the Weddell region to the total air-sea CO2 flux of the Southern Ocean [Lead: P. Monteiro (CSIR); participants: J. Boutin (SU), M. Hoppema (AWI)]
- Task 1.6: Estimate dissipation rate of turbulent kinetic energy and relate to the air-sea fluxes. [Lead: B. Ward (NUIG); participants: S. Swart (UGOT), M. Hoppema (AWI)]
WP co-leaders: S. Swart (UGOT) and M. Hoppema (AWI)
Other participants: B. Ward (NUIG), J. Boutin (SU), S. Josey (UKRI-NOC), P. Monteiro (CSIR)
- WP1: Air-sea fluxesWP2: Upper ocean ventilation pathwaysWP3: Deep ocean ventilation pathwaysWP4: Abrupt large polynya events shortcutting conventional pathwaysWP5: Impact on the coupled climate systemWP6: Variability and trends of heat and carbon uptake and storageWP7: Data management and connection with climate servicesWP8: Project management and dissemination