大象传媒

What is the ozone layer and why are people talking about it?

  • Published
Icebergs drift in the sea in Cierva Cove, on the coast of the Antarctic Peninsula in Antarctica. 17/12/2006
Image caption,

The largest hole in the ozone layer appears over Antarctica

The hole in the ozone layer above Antarctica is starting to get smaller, according to scientists.

But what is the ozone layer and why is it important?

What is the ozone layer?

Image caption,

Things like washing machines, fridges and hairsprays used to contain CFC gasses which harmed the ozone layer

The ozone layer is the part of the Earth's upper atmosphere where ozone, a form of oxygen gas, is found.

It absorbs UV radiation, preventing most of it from reaching us on the ground. This is important as UV radiation can harm humans, animals and plants.

Scientists first noticed a dramatic thinning of ozone above Antarctica in the 1980s.

It was being destroyed by gases called CFCs that were found in things like hairsprays, fridges and air conditioning units.

What's happened now?

Image source, SPL
Image caption,

This image shows the thinning of the ozone layer over Antarctica - which is beginning to heal itself.

The scientists say that in September 2015 the hole had shrunk by 4 million sq km since the year 2000 - an area roughly the size of India.

They think it's because CFC gasses were banned around the world.