Maths
Chemistry
Biology
English Language
History
Responding to change (a2 only)
Infection and response
Homeostasis and response
Energy transfers (a2 only)
Cell biology
Organisms respond to changes in their internal and external environments (a-level only)
Biological molecules
Organisation
Substance exchange
Bioenergetics
Genetic information & variation
Inheritance, variation and evolution
Genetics & ecosystems (a2 only)
Ecology
Cells
Show all topics
Britain & the wider world: 1745 -1901
1l the quest for political stability: germany, 1871-1991
The cold war
Inter-war germany
Medieval period: 1066 -1509
2d religious conflict and the church in england, c1529-c1570
2o democracy and nazism: germany, 1918-1945
1f industrialisation and the people: britain, c1783-1885
1c the tudors: england, 1485-1603
2m wars and welfare: britain in transition, 1906-1957
World war two & the holocaust
2n revolution and dictatorship: russia, 1917-1953
2s the making of modern britain, 1951-2007
World war one
Britain: 1509 -1745
Show all topics
Biology
11 Dec 2025
153
3 pages
Freya Clarke @freyaclarke_vfbl
Weather hazards like tropical storms and extreme cold can dramatically impact our lives, from the devastating Hurricane Katrina... Show more
Ever wondered why deserts are scorching hot during the day but freezing at night? It's all about global atmospheric circulation - the massive movement of air around our planet that creates weather patterns everywhere.
At the equator, hot air rises and creates a low pressure belt called the equatorial low. This is why you'll find tropical rainforests here - the rising air brings loads of rain and humid conditions. As this air rises, it cools and moves out to about 30° north and south of the equator.
Here's where it gets interesting most of Earth's deserts sit around 30° from the equator because the air is sinking here, creating high pressure. Sinking air means hardly any clouds, which is why deserts get baking hot days and bitter cold nights - there's nothing to trap the heat!
Quick Tip Remember that rising air = low pressure = wet weather, whilst sinking air = high pressure = dry weather.
For us in the UK, our weather comes mainly from south-west winds called westerlies. These bring our typical warm, wet conditions. However, when cold air from the north moves down, we get proper winter weather with snow and freezing temperatures.
Tropical storms are nature's most powerful weather machines, and they're not random - they follow specific rules that you can actually predict and prepare for.
These massive storms mainly develop near the equator in the tropics where sea temperatures reach 27°C or higher. Think of warm ocean water as fuel - the hotter it is, the more powerful the storm becomes. Once formed, tropical storms follow prevailing wind paths towards Asia and America, but they lose strength quickly when they hit land because their power source (warm ocean water) gets cut off.
The anatomy of a tropical storm is fascinating the centre is called the eye, where air descends and conditions are surprisingly calm. But don't be fooled - the eyewall around the eye is where you'll experience the most intense and dangerous weather.
Primary effects hit immediately buildings destroyed, crops damaged, bridges washed away. Secondary effects follow later food shortages, diseases from contaminated water, and blocked emergency services.
Remember Tropical storms need warm ocean water to survive - this is why they weaken over land.
We can fight back through prediction (satellites and radar give evacuation time), planning (training emergency services), providing aid (food, medicine, water), and education (teaching people to make survival kits).
Looking at actual disasters helps you understand how devastating weather hazards can be and why preparation matters so much.
Hurricane Katrina smashed into New Orleans in 2005, showing both the worst and best of disaster response. The storm killed 1,800 people and left 1 million homeless - that's like evacuating the entire city of Birmingham! Three million people lost electricity, creating chaos for weeks. However, 80% of people were evacuated before the storm hit, and emergency services saved 50,000 lives. The government provided $50 billion in aid to help rebuild communities.
The UK faced its own extreme weather during "The Big Freeze" of 2010. Brutal cold air from Siberia swept across Britain, killing 7 people and costing the economy £1.6 billion. People used twice the normal amount of gas trying to stay warm, putting massive strain on energy supplies.
Key Lesson Even developed countries like the UK struggle with extreme weather - preparation is everything.
The UK's response showed how preparation works schools closed for safety, extra gritters were deployed to keep roads open, and communities pulled together. Both case studies prove that whilst we can't stop extreme weather, smart planning and quick responses save lives and reduce damage.
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.
You can download the app from Google Play Store and Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
2
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the unique characteristics of hot desert ecosystems, focusing on the Sahara case study. This resource covers desertification, climate impacts, and adaptations of flora and fauna in extreme environments. Ideal for students studying geography and environmental science.
BiologyNotes describing the impact of humans on the environment
BiologyExplore the formation, impacts, and characteristics of tropical storms. This summary covers the economic, social, and environmental effects of tropical storms, as well as the conditions necessary for their development. Ideal for geography students studying weather hazards and climate change.
BiologyExplore the key factors shaping the UK's human landscape, including urbanization, migration trends, and economic shifts. This summary covers the Northern Powerhouse, land use zones, and the impact of globalization on urban and rural areas. Ideal for students studying geography and urban development.
BiologyApp Store
Google Play
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
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
Freya Clarke
@freyaclarke_vfbl
Weather hazards like tropical storms and extreme cold can dramatically impact our lives, from the devastating Hurricane Katrina to the UK's "Big Freeze" of 2010. Understanding global atmospheric circulation helps explain why these dangerous weather patterns develop where they do... Show more
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Ever wondered why deserts are scorching hot during the day but freezing at night? It's all about global atmospheric circulation - the massive movement of air around our planet that creates weather patterns everywhere.
At the equator, hot air rises and creates a low pressure belt called the equatorial low. This is why you'll find tropical rainforests here - the rising air brings loads of rain and humid conditions. As this air rises, it cools and moves out to about 30° north and south of the equator.
Here's where it gets interesting: most of Earth's deserts sit around 30° from the equator because the air is sinking here, creating high pressure. Sinking air means hardly any clouds, which is why deserts get baking hot days and bitter cold nights - there's nothing to trap the heat!
Quick Tip: Remember that rising air = low pressure = wet weather, whilst sinking air = high pressure = dry weather.
For us in the UK, our weather comes mainly from south-west winds called westerlies. These bring our typical warm, wet conditions. However, when cold air from the north moves down, we get proper winter weather with snow and freezing temperatures.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Tropical storms are nature's most powerful weather machines, and they're not random - they follow specific rules that you can actually predict and prepare for.
These massive storms mainly develop near the equator in the tropics where sea temperatures reach 27°C or higher. Think of warm ocean water as fuel - the hotter it is, the more powerful the storm becomes. Once formed, tropical storms follow prevailing wind paths towards Asia and America, but they lose strength quickly when they hit land because their power source (warm ocean water) gets cut off.
The anatomy of a tropical storm is fascinating: the centre is called the eye, where air descends and conditions are surprisingly calm. But don't be fooled - the eyewall around the eye is where you'll experience the most intense and dangerous weather.
Primary effects hit immediately: buildings destroyed, crops damaged, bridges washed away. Secondary effects follow later: food shortages, diseases from contaminated water, and blocked emergency services.
Remember: Tropical storms need warm ocean water to survive - this is why they weaken over land.
We can fight back through prediction (satellites and radar give evacuation time), planning (training emergency services), providing aid (food, medicine, water), and education (teaching people to make survival kits).
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Looking at actual disasters helps you understand how devastating weather hazards can be and why preparation matters so much.
Hurricane Katrina smashed into New Orleans in 2005, showing both the worst and best of disaster response. The storm killed 1,800 people and left 1 million homeless - that's like evacuating the entire city of Birmingham! Three million people lost electricity, creating chaos for weeks. However, 80% of people were evacuated before the storm hit, and emergency services saved 50,000 lives. The government provided $50 billion in aid to help rebuild communities.
The UK faced its own extreme weather during "The Big Freeze" of 2010. Brutal cold air from Siberia swept across Britain, killing 7 people and costing the economy £1.6 billion. People used twice the normal amount of gas trying to stay warm, putting massive strain on energy supplies.
Key Lesson: Even developed countries like the UK struggle with extreme weather - preparation is everything.
The UK's response showed how preparation works: schools closed for safety, extra gritters were deployed to keep roads open, and communities pulled together. Both case studies prove that whilst we can't stop extreme weather, smart planning and quick responses save lives and reduce damage.
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.
You can download the app from Google Play Store and Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
2
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the unique characteristics of hot desert ecosystems, focusing on the Sahara case study. This resource covers desertification, climate impacts, and adaptations of flora and fauna in extreme environments. Ideal for students studying geography and environmental science.
BiologyNotes describing the impact of humans on the environment
BiologyExplore the formation, impacts, and characteristics of tropical storms. This summary covers the economic, social, and environmental effects of tropical storms, as well as the conditions necessary for their development. Ideal for geography students studying weather hazards and climate change.
BiologyExplore the key factors shaping the UK's human landscape, including urbanization, migration trends, and economic shifts. This summary covers the Northern Powerhouse, land use zones, and the impact of globalization on urban and rural areas. Ideal for students studying geography and urban development.
BiologyApp Store
Google Play
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
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
Sociology