Download Clouds - Mr Young`s Geography Blog

Clouds
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Clouds are made when water vapour condenses into tiny droplets.
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There are many different types of clouds.
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The most common types of clouds are;
1.
2.
3.
Cirrus Clouds
Cumulus Clouds
Stratus Clouds
Rainfall
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Precipitation means hail, rain, sleet or snow.
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Rain is the most common type of precipitation.
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Rain occurs when warm air is forced to rise. As the warm air rises it cools. Cold
air cannot hold as much water vapour as warm air, so condensation occurs.
Clouds are formed and rain occurs.
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There are 3 different types of rain, because there are 3 different reasons why
warm air is forced to rise.
1.
2.
3.
Relief rainfall
Frontal (cyclonic) rainfall
Convectional rainfall
Relief Rainfall
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Relief rainfall occurs when;
- Warm moist air moves in from the sea.
- It hits a mountain range at the coast and is forced to rise.
- It cools as it rises.
- Condensation occurs, clouds form and it starts to rain.
Frontal Rainfall
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Frontal rainfall occurs when;
– Warm and cold air masses meet at a Front
– The warm air mass moves up over the cold air mass.
– The warm air cools and condensation takes place.
– Stratus clouds form and rain occurs.
Convectional Rainfall
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Convectional rain occurs when;
– The sun shines on the land and heats up the air above it.
– The heated air rises quickly.
– As it rises it cools and condensation occurs.
– Cumulus clouds are formed and heavy rain occurs.
The Weather
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When we talk about the weather we usually talk about the following
things.
1.
2.
3.
4.
5.
6.
7.
Temperature
Precipitation (rain etc)
Sunshine
Wind speed
Wind direction
Atmospheric pressure
Humidity
All of these different aspects of the weather can be measured.
There are different weather instruments to measure each thing.
These instruments are usually in a weather station.
Temperature
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Temperature is
measured using a
Thermometer.
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It is measured in
degrees Celsius (°C).
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Lines on a weather map
showing areas of equal
temperature are called
Isotherms.
Temperature
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You need to know how to calculate the;
1. Mean Temperature
2. Temperature Range
Mean Temperature: Add all the monthly temperatures, then divide by 12.
Temperature Range: Take the lowest temperature away from the highest temperature.
Mon
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sept
Oct
Nov
Dec
Mean
Monthly
Temp
10
13
15
17
18
21
23
28
21
15
12
11
Precipitation
• Precipitation is measured
using a Rain Gauge.
• It is measured in
millimetres.
• Lines on a map showing
areas of equal
precipitation are called
Isohyets.
Sunshine
• Sunshine is measured
using a Campbell Stokes
sunshine recorder.
• Sunshine is measured in
Hours per day.
• Lines on a weather map
showing areas of equal
sunshine are called
Isohels.
Wind
• We can measure 3 things about the wind.
• Wind Speed – Using an Anemometer.
• Wind Direction – Using a Wind Vane.
• Wind Strength – Using the Beaufort Scale
The Beaufort Scale
• The Beaufort Scale
describes the effect the
wind has on the
landscape.
• Wind strength is divided
into 12 forces.
• The Beaufort Scale was
invented by an Irishman.
Atmospheric Pressure
• Atmospheric pressure is
measured using a
Barometer.
• It is measured in millibars.
• Lines on a weather map
showing areas of equal
pressure are called
Isobars.
A Barograph can also be used to measure atmospheric pressure
Humidity
• Humidity is measured
using a Hygrometer.
• A common type of
hygrometer is a wet and
dry bulb thermometer.
• It is expressed as a %.
100% is the maximum.
The Greenhouse Effect
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The Greenhouse Effect occurs
naturally.
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When the sun shines it heats
up the earth.
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Some of the heat gets
trapped in gases in the
atmosphere.
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It is a positive thing because
without the Greenhouse
effect the earth would be too
cold for us to live on.
Global Warming
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Carbon dioxide and methane
are Greenhouse gases in the
atmosphere.
•
The amount of these gases
has increased a lot in recent
years.
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Therefore, more of the sun’s
heat is being trapped in the
atmosphere.
•
This is making the earth
warmer. This is called Global
Warming.
The Greenhouse Effect and Global Warming
Causes of Global Warming
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There are a number of reasons why Global Warming is taking place.
1.
There is a big increase in the amount of Carbon dioxide in the atmosphere.
2.
People are burning more fossil fuels, oil, coal, gas.
3.
Tropical rainforests are being cut down. Trees absorb C02 and so less trees means
more C02 in the atmosphere.
4.
There are more CFC’s in the atmosphere. These are bad gases which trap lots of the
sun’s heat.
The Effects of Global Warming
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Global warming will create many problems for people in the near
future. These include;
1.
2.
3.
The Polar ice caps will melt causing sea level to rise.
Low lying countries or regions may be flooded.
Some parts of the world will become drier. It will be more difficult for
farmers to grow crops.
This may lead to drought and desertification.
4.
However, it may also bring some positive things. Some countries that
are now cold may become warmer, allowing more crops to be grown.
Solutions to Global Warming
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If we want to stop the problem of global warming there are a number of
things we need to do. These include;
1.
2.
Stop using fossil fuels such as coal and oil.
Use more renewable energy sources such as wind, wave and solar
power.
Reduce Deforestation - Plant more forests and stop cutting down the
forests we have.
Encourage energy conservation - Save energy at home by using less
electric items and walk / cycle instead of using cars or buses.
3.
4.
Revision Questions
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Name 3 gases in the atmosphere.
Why does all of the energy from the sun not reach planet earth?
What does Latitude mean?
How does Latitude influence the temperature of a place?
What is wind and why does it occur?
What is the Coriolis Effect?
Name two Cold Ocean Currents and two Warm Ocean Currents.
List 4 air masses that effect Ireland’s weather?
What effect do each of these air masses have on Ireland’s weather?
Explain with diagrams the difference between a Cold and a Warm Front.
What is a Depression and what type of weather does it bring?
What is an Anticyclone and what type of weather does it bring?
Draw and label a diagram of The Water Cycle.
Revision Questions
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List 3 types of clouds.
List 3 types of rainfall and use diagrams to show how they are different.
List 7 things you can measure about the weather and draw the instrument used to
measure each thing.
What is the Greenhouse Effect and why is it happening?
What is Global Warming and why is it happening?
What effects is Global Warming having on our planet?
What can we do to solve the problem of Global Warming?