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Harry
05/12/2025
Chemistry
C14 - The Earth's Atmosphere
475
•
5 Dec 2025
•
Understanding Earth's Atmosphere: Greenhouse Gases and Climate Change
The Earth's Atmosphere and Climate Change
Your planet's early atmosphere was nothing like today's air you breathe. Volcanoes spewed out massive amounts of carbon dioxide, nitrogen, and smaller amounts of methane and ammonia - basically a toxic soup that would kill you instantly!
Everything changed when oceans formed from condensed water vapour. The CO₂ started dissolving into these new oceans, and carbonates precipitated out to form sediments on the ocean floor. Then green plants and algae evolved and began photosynthesis, taking in CO₂ and pumping out the oxygen we need to survive.
Today's atmosphere is roughly 78% nitrogen, 20.9% oxygen, 0.9% argon, and just 0.03% carbon dioxide. Those tiny amounts of CO₂ might seem insignificant, but they're absolutely crucial for keeping our planet warm through the greenhouse effect.
Key Point: The greenhouse effect isn't bad - without it, Earth would be a frozen wasteland! The problem is when we have too much of it.
The greenhouse effect works like this: short-wavelength radiation from the sun passes through our atmosphere and hits Earth's surface. Our planet then re-emits this energy as longer wavelength infrared radiation. Greenhouse gases like CO₂, methane, and water vapour absorb this infrared radiation, trapping heat and warming our atmosphere.
Unfortunately, human activities are pumping extra CO₂ into the atmosphere by burning fossil fuels and through deforestation. We're also increasing methane levels through cattle farming, rice paddies, and landfill sites. This enhanced greenhouse effect is causing climate change with serious consequences: rising sea levels, droughts, extreme weather events, and changes in wildlife distribution.
Atmospheric Pollutants and Their Effects
When we burn fossil fuels, we're not just releasing CO₂ - there's a whole cocktail of nasty pollutants being pumped into our air. Each one causes different problems, and you need to know what they are and how they affect us.
Carbon dioxide from burning any fossil fuel is the main driver of global warming. Water vapour also gets released but doesn't cause direct harm. The real nasties come from incomplete combustion and impurities in fuels.
Carbon monoxide forms when there isn't enough oxygen for complete combustion - it's a poisonous gas that can kill you. Solid particulates from incompletely burned solid fuels cause global dimming by blocking sunlight. Sulphur dioxide comes from burning coal (sulphur is an impurity) and causes acid rain plus breathing problems like asthma.
Remember: Nitrogen oxides form when nitrogen in air reacts with oxygen at the high temperatures in car engines - that's why traffic pollution is so problematic in cities.
Here's the frustrating bit - some people still deny that humans cause climate change! This happens because climate models are difficult to create (they're simplified versions of incredibly complex systems), and media coverage can be biased. Always check that scientific evidence is peer-reviewed before trusting it.
The solution involves reducing our carbon footprint - that's the total amount of CO₂ and other greenhouse gases emitted over the full life cycle of a product, service, or event. We can do this by using fewer fossil fuels, developing carbon capture and storage technology, eating less meat, and sending less food waste to landfill.
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Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
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Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
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This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
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I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
Understanding Earth's Atmosphere: Greenhouse Gases and Climate Change
Ever wondered how Earth went from a toxic, volcanic wasteland to the perfect planet for life? Our atmosphere has completely transformed over billions of years, but now human activities are changing it faster than ever before - and that's causing... Show more
The Earth's Atmosphere and Climate Change
Your planet's early atmosphere was nothing like today's air you breathe. Volcanoes spewed out massive amounts of carbon dioxide, nitrogen, and smaller amounts of methane and ammonia - basically a toxic soup that would kill you instantly!
Everything changed when oceans formed from condensed water vapour. The CO₂ started dissolving into these new oceans, and carbonates precipitated out to form sediments on the ocean floor. Then green plants and algae evolved and began photosynthesis, taking in CO₂ and pumping out the oxygen we need to survive.
Today's atmosphere is roughly 78% nitrogen, 20.9% oxygen, 0.9% argon, and just 0.03% carbon dioxide. Those tiny amounts of CO₂ might seem insignificant, but they're absolutely crucial for keeping our planet warm through the greenhouse effect.
Key Point: The greenhouse effect isn't bad - without it, Earth would be a frozen wasteland! The problem is when we have too much of it.
The greenhouse effect works like this: short-wavelength radiation from the sun passes through our atmosphere and hits Earth's surface. Our planet then re-emits this energy as longer wavelength infrared radiation. Greenhouse gases like CO₂, methane, and water vapour absorb this infrared radiation, trapping heat and warming our atmosphere.
Unfortunately, human activities are pumping extra CO₂ into the atmosphere by burning fossil fuels and through deforestation. We're also increasing methane levels through cattle farming, rice paddies, and landfill sites. This enhanced greenhouse effect is causing climate change with serious consequences: rising sea levels, droughts, extreme weather events, and changes in wildlife distribution.
Atmospheric Pollutants and Their Effects
When we burn fossil fuels, we're not just releasing CO₂ - there's a whole cocktail of nasty pollutants being pumped into our air. Each one causes different problems, and you need to know what they are and how they affect us.
Carbon dioxide from burning any fossil fuel is the main driver of global warming. Water vapour also gets released but doesn't cause direct harm. The real nasties come from incomplete combustion and impurities in fuels.
Carbon monoxide forms when there isn't enough oxygen for complete combustion - it's a poisonous gas that can kill you. Solid particulates from incompletely burned solid fuels cause global dimming by blocking sunlight. Sulphur dioxide comes from burning coal (sulphur is an impurity) and causes acid rain plus breathing problems like asthma.
Remember: Nitrogen oxides form when nitrogen in air reacts with oxygen at the high temperatures in car engines - that's why traffic pollution is so problematic in cities.
Here's the frustrating bit - some people still deny that humans cause climate change! This happens because climate models are difficult to create (they're simplified versions of incredibly complex systems), and media coverage can be biased. Always check that scientific evidence is peer-reviewed before trusting it.
The solution involves reducing our carbon footprint - that's the total amount of CO₂ and other greenhouse gases emitted over the full life cycle of a product, service, or event. We can do this by using fewer fossil fuels, developing carbon capture and storage technology, eating less meat, and sending less food waste to landfill.
We thought you’d never ask...
What is the Knowunity AI companion?
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
Where can I download the Knowunity app?
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Is Knowunity really free of charge?
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This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
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Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
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Best app on earth! no words because it’s too good
Thomas R
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Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user