The ozone is a naturally occurring gas made up of three oxygen atoms. It forms a shield that protects life on Earth from the Sun's UV radiation.
What is the difference between higher level and ground-level ozone?
Stratospheric 'good' ozone:
90% of the ozone in the atmosphere sits in the stratosphere. The level of ozone depends on the balance between sunlight that creates ozone and chemical reactions that destroy it. The sunlight splits oxygen (O2) apart into single atoms, these single atoms can join together again (O2) or they can join onto an existing O2 to create ozone (O3).
Ok professor, let's break that down. Two friends go to a party, they have an argument and separate, one friend finds another solo pal to hang with (the oxygen/O2 crew) and the other finds couple to hang with (the ozone/O3 crew). Are we following now?
The Ozone crew is destroyed when it reacts with molecules containing nitrogen, hydrogen, chlorine or bromine. Some of these baddies occur naturally, but others were created by humans (hello CFCs and HFCs)!
Tropospheric 'bad' ozone:
This is theground-level ozonethat forms when nitrogen oxide gases from vehicles and industrial emissions react with carbon-containing chemicals that evaporate easily into the air (e.g. paint thinners). High levels can be detrimental to our health. Eeeep!
Why is the ozone important?
It's like going to the beach in the middle of summer without an umbrella, the ozone protects the earth from the UV radiation from the Sun. Without it, the UV radiation would sterilise the earth's surface
How did humans get involved?
CFCs (chlorofluorocarbons), HFCs (hydrofluorocarbons), and halons: AKA super greenhouse gases, are manufactured for use in refrigeration, air conditioning, foam blowing, aerosols, and fire protection systems. These baddies are responsible for speeding up the depletion of the ozone layer, resulting in a hole above Antarctica!
Over 30 years ago, when scientists discovered that these guys were linked to ozone depletion, the world banded together to created the Montreal Protocol. This protocol banned ozone-depleting substances. CFCs and halons were the first to be phased out and HFCs are set to be phased out by 2030 in developed countries and 2040 in developing countries.
This protocol has averted more than 135 billion tonnes of carbon dioxide equivalent emissions from 1990 - 2020. *woot woot*
What is the ozone hole?
Ok, so it'snot technically a hole, but it is a region of stratospheric ozone where it is significantly thinner than the rest. In1985, a group of scientists published in the journal of Nature the first paper that recognised springtime losses of ozone over Antarctica. Over the following years, the role of chlorine in ozone loss because more and more evident. The higher the level of Chlorine, the lower the level of ozone!
When will the ozone heal?
The UNEP predicts that Northern Hemisphere and mid-latitude ozone will completely heal by the 2030's, the Southern Hemisphere by 2050's, and the Polar Regions in the 2060's. Whist this progress is groundbreaking, we still need to remain vigilant to stop any new illegal sources of harmful emissions.
This is proof that the fight against climate change is possible if countries around the world join forces. Keep using your voices and spreading awareness! We've got this!!