Weather Unit

Question 1

Explain how Altitude affects the UK Climate

Answer 1

• The sun’s rays are made of visible UV radiation. This UV radiation cannot heat up the gases of the atmosphere very efficiently. It can however heat up the Earth’s surface.
• The surface absorbs the UV radiation and releases heat in the form of infra-red radiation. This infra-red radiation can heat up the atmosphere.
• As the altitude increases the air becomes thinner this means it is less able to hold onto heat.
• This is why for every 100m you climb in height you lose 1 degree celcius
• This is also why higher, mountainous areas are colder than flat land close to the sea

Question 2

How does Latitude affect the UK’s climate

Answer 2

• Places closer to the equator receive the most heat and sunlight from the sun and places closer to the poles are colder
• This is because the Earth is in the shape of a sphere. And the widest part of the sphere is the equator. Because the widest part of the Earth is the equator, it sits closest to the sun
• When you move towards the poles the Earth slopes away from the sun
• Due to the angle that the Earth sits on its axis the sun’s rays strike the equator directly, this means its energy is concentrated
• But at the poles the sun’s rays have to strike a much larger area this means its energy is less concentrated
• As well the atmosphere is thicker at the poles compared to the equator this reduces the amount of heat and light that reaches the poles

Question 3

How does distance from the sea affect the UK’s Climate

Answer 3

• During the summer the land is warmer than the sea
• This is because the sun is only able to heat up the upper-layers of the land. this means the land heats up quickly
• However, the sea is a vast area of liquid this means the sun’s rays are able to penetrate down many meters into it. This means the sea takes longer to heat up compared to land
• But at the end of the summer, the land quickly loses the heat it has gained, but because the sea has been heated to a greater depth it is now at its highest temperature. This means the sea is now warmer than the land
• This is why coastal areas are warmer than inland areas during the winter

Question 4

How does aspect affect the UK’s climate

Answer 4

• Due to the angle that the sun strikes the northern hemisphere south - facing slopes receive more heat and sunlight than north - facing slopes
• During the winter the angle of the sun is even lower this means the effects of aspect are even greater
• Often during the winter north - facing slopes will sit in the shade for several weeks. Making them much colder than south - facing slopes

Question 5

What is an anticyclone like during the winter

Answer 5

• Due to a lack of cloud cover during an anticyclone the temperatures drop right down. This is because clouds act like a blanket that keeps the heat near the Earth’s surface so without it some of the heat escapes into space
• This will often mean that during an anticyclone in the winter there is frost in the morning. This is because it gets so cold at night that any moisture on the ground freezes.
• Fog or mist can sometimes also form in the morning. This is because the ground surface is colder than the air above it. This is called a temperature inversion and can cause clouds to form at ground level
• As the surface warms up throughout the day the frost may melt or the fog may lift. If surface temperatures do not rise much frost and fog may remain for the whole day.

Question 6

What is the weather like at a cold front

Answer 6

1. Marks the front of an area of air that is colder than the air in front of it
2. Cold air moves faster than warm air so the cold air from a cold front has catches up with the milder air at the warm sector.
3. As the cold front moves in the wind direction suddenly changes from W to NW. This sudden change in wind direction creates gusty winds
4. The cold air undercuts the warm air very rapidly, this causes large cumulonimbus clouds to form. They bring heavy rain
5. As the cold front moves away the rain becomes lighter and then turns to showers. The air is colder as winds are coming from the NW.

Question 7

What is the weather like at an occluded front

Answer 7

1. Occluded fronts sometimes form at the top of a depression where a cold front has moved in very quickly
2. The cold air that is in front of the warm air creates a wedge that the warm air has to travel over
   3.Meanwhile cold air from the cold front is cutting into the warm air in a warm sector
3. This causes cumulonimbus clouds to form very rapidly
4. Occluded fronts bring short torrential downpours and strong winds

Question 8

What is the weather like at a warm sector

Answer 8

1. A warm sector marks an area of warmer/milder air behind a warm front
2. The warmer/milder air does not come into any contact with cold air
3. This means less air is rising, as less air is rising less cloud is produced
4. This causes the rain to become lighter or stop altogether
5. Because less air is rising winds will drop
6. The wind direction changes to westerly

Question 9

What is the weather like at a warm front

Answer 9

1. A warm front marks the front of an area of air that is warmer than the air ahead of it
2. When warm air and cold air meet the warm air is forced to rise up above the cold air as it does so it cools, condenses and forms low sheets of nimbostratus clouds
3. Nimbostratus clouds release long periods of steady rain
4. Because air is rising air pressure drops which causes winds to increase
5. Air from high pressure areas nearby rush in to replace the escaping air, this movement creates winds