Ozone-hole' means

Ozone hole is

Ozone hole is

Ozone hole is measured in

Ozone hole enhances

The result of Ozone hole is

Assertion (A) : The decline in the thickness of the ozone layer over restricted area is called ozone hole. Reason (R) : An Ozone hole is really not a hole but rather a thinning of the ozone layer in the stratosphere.