1.   Chlorine monoxide, a known cause of ozone depletion in the stratosphere above polar regions, has been discovered in the upper atmosphere over temperate latitudes.

2.   Levels of ozone-destroying chlorine monoxide are the highest ever observed.

3.   NASA satellite surveys had revealed record levels of chlorine monoxide over parts of North America and Europe during some days in January.

4.   Chlorine monoxide is among the chemicals from man-made sources most closely linked to the destruction of ozone.