 Solomon, working with colleagues at the NOAA Earth System Research Laboratory, postulated the mechanism that the Antarctic ozone hole was created by a heterogeneous reaction of ozone and chlorofluorocarbons free radicals on the surface of ice particles in the high altitude clouds that form over Antarctica.In 1986 and 1987 Solomon led the National Ozone Expedition to McMurdo Sound, where the team gathered the evidence to confirm the accelerated reactions.Solomon was the solo leader of the expedition, and the only woman on the team.