Tropospheric ozone depletion events and air mass origin at Arrival Heights (Antarctica)
Degree GrantorUniversity of Canterbury
Degree LevelPostgraduate Certificate
Degree NamePostgraduate Certificate in Antarctic Studies
Surface ozone (03) measurements made between 1997 and 2003 at Arrival Heights, Antarctica (77.8°S, 166.7°E), show sudden decreases in 0 3 mixing ratios during Antarctic springtime. These low 0 3 events are often correlated with elevated concentrations of bromine oxide (BrO). The air mass origin during these 0 3 depletion events was investigated by calculating 5-day back trajectories. Trajectory analysis revealed that air masses had either contact with sea-ice, which was correlated with enhanced BrO columns, or were transported across the Antarctic continent, which led to 0 3 depletion events without elevated BrO concentrations. In 1997-1998 less frequent high BrO events were observed at Arrival Heights probably due to increased sea ice coverage in the Ross Sea during these El Nino years.