You cannot see the ozone layer but it is there and it is a vital protective layer for Earth against the Sun’s harmful rays Protecting Planet Earth Have you ever wondered what is up there in our atmosphere On a hot day do you think about the Sun’s rays and protect your skin from burning by using Sun Protection Factor SPF lotion How is it that we don’t get burned at other times Did you know that there’s a natural sunblock up there in the sky that’s under threat Climate control Our planet comes with an in-built SPF called the ozone layer It was formed millions of years ago and without it life on Earth as we know it would not exist The ozone layer is an invisible layer of gas high in the upper atmosphere on the edge of space It keeps the climate under control and acts as a filter against the most harmful of the Sun’s rays 4
Without the ozone layer to protect us sunny beach holidays could be under threat in the future Global protection It is not just human skin that needs protection from the Sun but every living thing on Earth From fish in the ocean and coral reefs to farmland and crops and even the ice caps at the North and South Poles everything depends on the ozone layer But the ozone layer is under threat It is at risk of disappearing What is causing this And can it be reversed Fragile layer Natural processes on Earth are often interlinked When something happens such as the ozone layer thinning or even disappearing it can trigger a series of actions that can have devastating effects This book looks at the causes and effects of ozone damage What will happen if the ozone layer disappears 5
Life Support Think of the Earth as having an invisible blanket all around it keeping it safe In the 1980s (cid:90)(cid:74)(cid:80)(cid:76)(cid:85)(cid:91)(cid:80)(cid:90)(cid:91)(cid:90)(cid:3)(cid:73)(cid:76)(cid:78)(cid:72)(cid:85)(cid:3)(cid:196)(cid:85)(cid:75)(cid:80)(cid:85)(cid:78)(cid:3)(cid:74)(cid:83)(cid:92)(cid:76)(cid:90)(cid:3)(cid:91)(cid:79)(cid:72)(cid:91)(cid:3)(cid:91)(cid:79)(cid:80)(cid:90)(cid:3)(cid:73)(cid:83)(cid:72)(cid:85)(cid:82)(cid:76)(cid:91)(cid:19)(cid:3) the ozone layer was thinning or even vanishing in places The scientists were alarmed by these holes because they did not know what was causing them Ozone depletion is at its most extreme at the two poles At the North Pole the hole in the ozone layer is larger than the hole over the South Pole shown here in 2010 6 Green and yellow areas indicate the most ozone Blue and purple areas indicate the least ozone
Stratosphere Troposphere 30 miles 50 km 12 miles 20 km Ozone in the stratosphere acts as a shield protecting us from harmful UV rays The ozone in the troposphere is a pollutant and damages life on Earth 7 Number Crunchin g Scientists have calculated that a 1 percent depletion in the ozone layer would allow 2 percent more ultraviolet radiation to reach the Earth’s surface In turn this means that the rates of skin cancer would rise dramatically Ozone is a natural gas that is found in two different layers of the atmosphere One layer called the troposphere is at the Earth’s surface where we live Ozone released in the troposphere harms life on Earth because it dirties the air and helps make smog which is unhealthy to inhale The other layer called the stratosphere begins at around 12 miles 20 km above the Earth’s surface and ends at around 30 miles 50 km above the Earth’s surface Ozone in the stratosphere protects life on Earth by absorbing some of the Sun’s harmful ultraviolet UV rays Deadly sunshine The thinning of the ozone layer allows more UV light to reach the Earth’s surface UV light and radiation from the Sun can cause cancer in humans It can also destroy plants and disrupt life cycles It is extremely powerful and can change the whole balance of life on our planet Where is ozone found
