Climate change and its impacts are of much concern globally and to the Antarctic Treaty System given realised and expected impacts on global sea level rise and biodiversity.
The recent Special and Assessment Reports of the Intergovernmental Panel on Climate Change (IPCC) provide the clearest current summaries of global climate change that has taken place, impacts that are being realised, and changes that are forecast.
Attention is drawn here to key findings from these IPCC Reports, focussing on substantial uncertainties about global, Antarctic and Southern Ocean impacts; and to the research being undertaken through SCAR to address these uncertainties. The paper presented here is not intended as a comprehensive synthesis.
Key uncertainties include the current and future behaviour of the Antarctic cryosphere (notably implications for global sea level and coastal populations and infrastructure); climatic variability over short timescales which is especially important given its significance for impacts and operational forecasts; and the future of Antarctic marine biodiversity, approaches to improve its conservation, and ways to mitigate climate change impacts on both.
Quantifying and reducing these uncertainties through focussed research is critical.
More critical is the need to convey to nations the importance of the Paris Climate Agreement, and expected strengthening of greenhouse gas emissions reductions targets, for maintaining Antarctic and Southern Ocean environments and their biodiversity.