6 research outputs found
The Antarctic ozone during 2010
The Antarctic ozone hole of 2010 is reviewed from a variety of perspectives, making use of various data and analyses. Based on total column ozone metrics, the
2010 ozone hole was one of the smallest in the past fifteen–twenty years. The main influence on the size of the ozone hole was relatively warm temperatures in the Antarctic lower stratosphere which impeded ozone depletion in the austral spring. The warm winter temperatures were associated with a significant dynamical
disturbance in the mid- and high latitude upper stratosphere during July which included a substantial warming of the mid- and upper extratropical stratosphere,
a deceleration of zonal winds and a cooling in the polar mesosphere. The disturbance was likely influenced by the phase of the Quasi-Biennial Oscillation
(QBO) which favoured a weak and disturbed polar vortex in the winter months. The winter warming also resulted in significant off-pole displacement and weakening
of the polar vortex in the mid- to upper stratosphere, producing a long-lasting increase in the overburden of ozone and weakening ozone hole metrics based
on total column ozone measurements. Ozone loss in the lower stratosphere was less markedly affected by this dynamical activity, and was similar to other recent years. A notable feature was the reduction in dynamical disturbances of the polar vortex after September, when the QBO moved into a strongly eastward phase. During the late spring and early summer, stratospheric temperatures warmed more slowly than in recent years, and this produced one of the longest-lasting ozone holes yet observed which eventually disappeared in the last week of December.
The relatively low ozone levels in December resulted in unusually high surface ultraviolet fluxes as measured on the coast of East Antarctica
The Antarctic ozone hole during 2008 and 2009
The Antarctic ozone holes of 2008 and 2009 are reviewed from various perspectives, making use of a range of Australian data and analyses. In both years, ozone holes formed that were fairly typical of those observed since the late 1990s. The ozone hole of 2008 was somewhat larger than that of 2009. In 2009 the ozone hole developed more rapidly, but did not last as long as in 2008, particularly
in the lower stratosphere