Unit 2 (4) - Air Pressure, Winds

Question 1

What is air pressure?

Answer 1

Air pressure (atmospheric pressure): the downward force exerted by air on the Earth’s surface

Measured in millibars (mb) using a barometer

Low pressure occurs when altitude is higher.
Air molecules are far packed, and air becomes thinner.

High pressure occurs when altitude is lower. Air molecules are closely packed, and air becomes denser.

Question 2

Formation of sea breeze (DAY)

Answer 2

LAND (higher temp, lower pressure)
Air over the land surface heats up. Warm air expands and rises, lowering air pressure over the land.

Air cools and sinks.

SEA (lower temp, higher pressure)
Air moves from an area of high pressure (sea) to an area of low pressure (pand) as a sea breeze.

Question 3

Formation of land breeze (NIGHT)

Answer 3

LAND (lower temp, higher pressure)
Air moves from an area of high pressure (land) to an area of low pressure (sea) as a land breeze.

SEA (higher temp, lower pressure)
Warm air expands and rises, lowering air pressure over the sea.

Air cools and sinks.

Question 4

Full answers about land and sea breezes :)

Answer 4

A sea breeze is wind that blows from the sea to the land. During the day, the land heats up faster than the sea. The warm air over the land rises. As a result, the air pressure over the land is lower than the sea. The area over the sea is a high pressure area. Therefore, wind blows from the sea to the land during the day to form a sea breeze, because air moves from an area of high pressure to an area of low pressure.

A land breeze is wind that blows from the land to the sea. At night, the sea loses heat slower than the land. The warm air over the sea rises. As a result, the air pressure over the sea is lower than the land. The area over the land is a high pressure area. Therefore, wind blows from the land to the sea at night to form a land breeze, because air moves from an area of high pressure to an area of low pressure.