The lack of reliable and long observational records of sea surface temperature (SST) from the Southern Ocean remains a key factor in limiting our attempts to understand climate variability on interannual to centennial scales in the Southern Hemisphere. The Law Dome, Dome Summit South (DSS), ice core from East Antarctica, provides an annually resolved climate record, capturing atmospheric and ocean processes from the Pacific and Indian sectors of the Southern Ocean. Previous work has shown this record provides useful proxy data can be exploited for the study of the long term variability of global climate signals, and in particular Australian climate and rainfall. We present a 1000 year reconstruction of global SST using snow accumulation rate and sea salt records from the DSS ice core. The sea salt aerosols recorded at Law Dome provide a proxy for wind speed over the source region of the moisture, and thus, through the relationship between ocean-atmospheric heat exchange and wind speed, are a proxy for SST.  Back trajectory analysis of precipitation for 1990-2010 from ERA-Interim reanalysis data shows the origin of the moisture falling as snow on Law Dome is predominately from the Indian Ocean sector of the Southern Ocean, providing further evidence of a relationship between sea salt concentrations in the DSS ice core and wind speed from the source region. Examination of the time series of the the dominant temporal modes of the SST reconstruction shows a break point in the time series at 1259CE. This shift is coincident with a series of volcanic eruptions also recorded in the same ice core archive, (but in an independent proxy not used for the SST reconstruction), thus eliminating timing uncertainties between the two events and suggesting that the end of Medieval Climate Anomaly was influenced by climate responses to the eruptions.