Advancing understanding of and capability to predict the ocean’s impact on climate change 

Led by BAS, in partnership with CPOM, NOC, BGS, PML and the Sea Mammal Research Unit, ORCHESTRA is combining data collection, analysis and computer simulations to radically improve our ability to measure, understand and predict the circulation of the Southern Ocean.  By improving current models, ORCHESTRA will address uncertainties regarding the uptake and storage of heat and carbon by the ocean and how this influences global climate.

sea ice around Antarctica

Sea ice around Antarctica. Credit: BARON REZNIK/FLICKR (CC BY-NC-SA 2.0)

The Antarctic polar seas are regions of complex interactions between the ocean, atmosphere and cryosphere, affecting the stability of the ice sheet, sea ice cover, Earth’s albedo, and the formation of Antarctic Bottom Water which ventilates much of the global ocean. Increased freshwater discharge from Antarctica and decadal changes in atmospheric forcing, linked partly to greenhouse gas emissions, are now altering the Southern Ocean, but our understanding of the impacts is extremely limited due to the complexity of obtaining satellite observations in the presence of near-perennial sea ice.

CPOM is helping ORCHESTRA to address this by creating and analysing satellite observations of sea ice and ocean topography in the ice-covered Southern Ocean, providing unique data on the dynamics of the region. Combining these with numerical simulations has improved our understanding of ocean circulation and the nature of air-sea exchanges.