Question

‘Ozone-hole’ means

Options

• a large-sized hole in the ozone layer

• thinning of the ozone layer

• small holes scattered in the ozone layer

• thickening of ozone in the ozone layer

Answer 1

thinning of the ozone layer

Explanation:

The ozone layer, comprising a high concentration of ozone about 18-50 km above in the atmosphere is called an ozone blanket. Production and release of high levels of an ozone-depleting substance (ODS) particularly chlorofluorocarbons have resulted in thinning of the ozone layer over a restricted area. Such an area is termed an ozone hole.
The ozone hole was first discovered over Antarctica in 1985. The amount of atmospheric ozone is measured by Dobson spectrometer and is expressed in Dobson units (DU).