According to a 2007 research project, the current atmospheric theories regarding depletion of the Earth's ozone 'layer' at the poles only account for around 40% of the actual depletion as measured by NASA. See: Is a major fraction of polar ozone loss due to a currently unknown mechanism ? (Alfred Wegener Institute for Polar and Marine Research, Potsdam, Germany)

An article covering the anomaly was published in Nature: Chemists poke holes in ozone theory, issue 449, 382-383.

The research results were not universally accepted by climate scientists.

There were also reports of large-scale emissions of 'banned' ozone-destroying gases used for refrigeration and air-conditioning etc., which go undeclared and may have been overlooked.

Also see : Ozone Depletion Eventsplugin-autotooltip__plain plugin-autotooltip_bigOzone Depletion Events

The Earth's Troposphere regularly experiences (naturally occurring *) ozone depletion events. The presence of atmospheric ozone is of extreme importance to organic life, as it substantially 'filters out' a large proportion of dangerous UV radiation from the Sun before it reaches the Earth's surface.