DMSP in Antarctic pack and fast ice

In Polar Regions, sea ice has a marked influence on interactions between the coupled ocean-atmosphere system. The contribution of the sea ice zone to the global flux of dimethylsulphide (DMS), a trace sulphur gas implicated in climate change, has been of interest for over a decade. The first flux estimates of DMS from the Antarctic Zone and Seasonal Ice Zone by Curran and Jones (2000) suggests that the emission of DMS from this region is 17% of the global emission estimate, and is likely to be higher when DMS released from the sea ice surrounding Antarctica is more accurately characterized. Studies of DMSP (the precursor compound of DMS) in Antarctic sea ice are sparse, with the current data set consisting of less than 200 measurements. During three spring/summer voyages to the eastern Antarctic sea ice from 1997-2000, sixty-two sea ice cores were collected from sites distributed across several thousand km of sea ice. These cores have provided the basis to investigate DMSP concentrations in sea ice at a range of spatial scales, and to investigate its relationship with a range of physical, biological and chemical sea ice properties. This presentation focuses on the variability of DMSP in eastern Antarctic pack and fast ice, and investigates its variability and relationship with chlorophy a, with sea ice thickness, and its seasonality through spring and summer. The overall goal of this study is to estimate the flux of DMS from the Antarctic sea ice zone during various stages of ice cover and sea ice melting.