Project: Atmosphere-ocean interactions
Alignment with ASP projects:
- Project 1 Objective 3: Future response and Projections
- Project 3 Objective 1: Climate Effects on Terrestrial Habitats and Biogeography
- Project 4 Objective 1: Seasonal to Interdecadal Variability of Sea Ice in the Ross Sea
- Project 4 Objective 3: Polynya Processes
Hub Contributors Alena Malyarenko, Alexandra Gossart, and Mario Krapp, and Nikhil Hale
The broad aim of this project is to study past, present and future ocean-atmosphere-sea ice interactions at regional scale over the Ross Sea. We have developed a new, coupled model setup that is physically consistent in the representation of ocean/atmosphere/sea ice interactions for polar climates (Malyarenko et al, 2021 *as a link to publications*). The model couples the MITgcm ocean component to the PWRF atmosphere part using the Earth System Modeling Framework (ESMF). The grid of the models are at approximately 10 km horizontal resolution on a polar stereographic grid and contain 210 x 240 grid cells and 61 model levels in the atmosphere and 70 in the ocean.
The figure to the right shows the model domain delineated in red, and the topography and bathymetry in colors.
With this model, we want to look at :
- Polynyas and sea ice representation (sea ice cover, thickness, changes,...), (Alex and Alena).
- In this research, we look at sea ice. Our model is able to represent polynya opening in winter and we are able to simulate the dynamical changes of sea ice : wind blowing the sea ice away as well and the thermodynamics (sea ice formation by the ocean)
High salinity shelf water production and circulation under the ross ice shelf cavity, (Alex and Alena and Nikhil)
We use this model to investigate Polynya activity in a colder and warmer setting. The aim of this project (Nikhil’s PhD) is to understand the link between the Ross Sea Polynyas and the basal melting of the Ross Ice Shelf Cavity. Given its area and the intensity of sea ice production in the Ross Sea Polynya, it contributes significantly towards High Salinity Shelf Water production that floods the RIS cavity, shields it from Circumpolar Deep Water intrusion and drives basal melting of the ice shelf. In case of decreased sea ice production (less active, weaker Ross Sea Polynya) we might see the protection of the High Salinity Shelf Water gone, and intrusions of Circumpolar Deep Water into the cavity.
- How the sea ice cover impacts local atmospheric circulation and meso-cyclones (Alex and Alena - University of Canterbury)
- With this model, we also investigate meso cyclone paths over the Ross Sea. We identified a mesocyclone from the 6th to the 8th of January 2014 The cyclone starts spinning from the coast of Victoria Land and moves over the open ocean and loses intensity and disappears once it gets to the sea ice edge.
- The mesocyclone is present in different models (ERA5, REGcm, AMPS and P-SKRIPS). The timing and trajectory of the cyclone is coherent.