Before Shackleton arrived at South Georgia aboard Endurance on 5 November 1914 he was aware that the vessel might meet bad pack-ice in the Weddell Sea. This had been forecast on the basis of climate analysis by Robert Mossman, the meteorologist on the Scottish National Antarctic Expedition (1902–1904), who was currently working at the Argentine Meteorological Office. Mossman was interested in teleconnections linking meteorological and oceanic conditions in widely separated places and had studied the links between the Weddell Sea and South America. Mossman's Antarctic data were mainly records from the Orcadas station in the South Orkneys which had operated continuously from 1903. He found a correlation between extensive pack-ice in the Weddell Sea and plentiful rain in a belt across South America that included Buenos Aires. The experiences of Endurance supported this. Modern studies of the El Niño-Southern Oscillation (ENSO) broadly confirm Mossman's conclusions.