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Name: Rebecca
Status: Student
Age: 9
Location: N/A
Country: N/A
Date: N/A 


Question:
In weather, what does high pressure and low pressure mean?



Replies:
Hi Rebbecca

You make a high pressure when you squash lots of air into a small space. Imagine you were pumping up a bicycle tire. You can pump a lot of air into a tire - more air than would normally fit into a space the size of a bicycle tire. The air inside the bicycle tire is at a high pressure.

When they talk about high and low pressure in the weather they mean that sometimes the air above a n area of land can get slightly more squashed up than is normal. This is a high air pressure. The reverse can also happen - the air can be slightly more spread out than normal and this is called a low air pressure.

When there is a high pressure in the air above a piece of land there is nothing to stop it spreading out into the air that is at a low pressure. When you get a high pressure bit of air next to a low pressure bit of air the air will move from the high pressure to the low pressure. This movement of air is wind.

Thanks for the question.

Cameron Millsom



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