9. Water in the Atmosphere

Weather and Climate: a Teachers’ Guide

Pathway: Basic weather 

Climate ZonesAir MassesPressure and Wind – Water in the Atmosphere

Lesson overview: In this lesson, we focus on cloud formation due to convection, orography (relief) and frontal uplift.

The atmosphere is one of the smallest reservoirs of water in the hydrosphere.  Clouds form when air is cooled. Air can cool due to convection, when air is heated from below and rises, or when air is forced to rise at a front between two air masses. When air is forced to rise over hills and mountains, cloud formation is enhanced. Climate change will intensify the water cycle, increasing the amount of water vapour in the atmosphere.  As water vapour is a greenhouse gas this creates a positive feedback loop, amplifying climate change.

Learning objectives:

  • To understand why clouds form in the atmosphere.

  • To be able to explain two ways in which clouds form

Key Teaching Resources

Water in the Atmosphere PowerPoint
Water in the Atmosphere PowerPoint (easier)
Water in the Atmosphere Worksheet
Water in the Atmosphere Worksheet (easier)
Back-to-back image

Teacher CPD/ Extended Reading

Water in the Atmosphere – More for Teachers

Alternative or Extension Resources


Weather and Climate: a Teachers’ Guide

Weather Charts Teachers’ Notes

Understanding weather charts

Teachers’ notes to accompany Understanding Weather Charts

Resources required

Computers with Internet access would be desirable. Alternatively if Internet access is not available, printed copies of student sheets and worksheets should be made.

Prior knowledge required

A basic background of weather and climate.

Teaching activities

Students can visit the following pages to gain a basic background into the topics covered:

The information on the student sheets can be delivered by the teacher and activities completed individually. Alternatively students can work through the whole lesson themselves.

Part A – Isobars, pressure and wind

Part B – Identifying pressure systems and fronts

Part C – Plotted weather charts


Three worksheets with exercises are provided to consolidate learning.

A series of additional exercises are provided for more able students, or those who have already studied pressure systems and fronts in more detail prior to this lesson.

Suggestions for homework

Any of the worksheet activities can be completed. Alternatively students can collect weather charts from the Internet or a newspaper and repeat the exercises using these.

Web page reproduced with the kind permission of the Met Office


By the end of the lesson, you will be able to:

  • Identify and explain what a flood plain is
  • Use the internet to search for specific information on a local area
  • Apply maths to calculate changing meteorological conditions
  • Compare numerical geographical data and apply findings

See Also

flood symbolsTeachers’ notes

Extension exercise

Flooding Lesson Plan

Flooding – where and how?

After completing this small project about flooding, you will be able to:

  • search the Environment Agency web site to find information about flooding in your local area and another area of Britain 
  • explain what a flood plain is and the risk of flooding there
  • explain why flooding is a serious issue
  • compare average rainfall to the actual conditions in October 2000

Task 1

  • Click on the following web address www.environment-agency.gov.uk to open up a new window
  • In the home and leisure section you will find a box called ‘What’s in your backyard?’.
  • Select flood maps and type in your school’s postcode and press ENTER. (Remember postcodes must be capital letters and have a space between the two sets, e.g. GU16 7FR.)
  • There should be a map of your area on the screen. Look to the right of the map at the Key 

Task 2

Open a new document in Word and give it the title: Flooding — where and how? Add the date and your name(s).

Keyboard Shortcut — To move between the internet window and Word window, press the Alt and Tab keystogether.

Using the map, write down:

  • Whether your school is in a flood plain;
  • If it is, explain what type of flood plain it is? (Hint: look at the colour on the key.)
  • If your school is not in the flood plain, use the enlarge and reduce buttons to zoom out.
  • What is the nearest place to the school that is in the flood plain?

Now SAVE your work.

Task 3

Look again at the page about indicative flood plain maps.

Read the ‘Understanding the flood map’ and then scroll down and read ‘Flood map – your questions answered’ .

Now go back into Word.Type flood plain in bold and, in your own words (do not cut and paste text), explain what a flood plain is.

Also: Explain what percentage chance there is of flooding each year in both types of flood plain. (Remember to use the percentage sign to show this.)

Now SAVE your work.

Good. You should now know what a flood plain is and if your local area is in the flood plain. Now we will investigate why flooding happens.

Before we move to another web site, copy and paste the sentence below into Word and use what you have just learned to fill in the blanks.

Flooding is serious because __________ properties are in the flood plain. Flooding is caused by different extreme weather conditions such as _______________.

You should now fully understand what a flood plain is and where to find information about local flood plains.

Now SAVE your work.

Task 4

Click on the web address below and select Averages maps, October and rainfall. You should see a map of Great Britain with rainfall in millimetres marked on it. This map shows the average rainfall in October over 30 years (1981-2010). The contour lines on the map show these amounts.


Now click on the next web address (below). This map shows the actual rainfall for October in 2000 when there were a number of severe floods.


Using these two maps you will be able to complete the following table.

LocationOctober 2000
average (mm)
Difference from
average (mm)
Anomaly (%)

Reproduce the above table in your Word document. In the blank row, under location, enter your school name.

Now SAVE your work

Task 5

Now we will look at the big differences in the rainfall amounts that caused the serious flooding in 2000. To do this we will compare the actual amount of rainfall in October 2000 with the average rainfall between 1961 and 1990. Then we will use some maths to work out the difference in rainfall as a percentage.

  1. For your area, calculate the difference between the actual rainfall in October 2000 and the average in millimetres. To do this, use the equation below.difference = actual rainfall in October 2000 (mm) — 30-year average for October (mm)Add this to your results table
  2. We can also work out the difference as a percentage. This is called an anomaly (the percentage difference between the actual rainfall and the rainfall average). To do this, use the equation below.




Task 6

Add this to your results table

In October and November 2000 there were record-breaking floods. These were spread across the country, but three places that were especially badly effected were York (Yorkshire), Shrewsbury (in Shropshire) and Lewes (Sussex).

Use all the knowledge you have gained so far to explain why Britain had such bad flooding in Autumn 2000.

  • You have evidence about which areas are in the flood plain
  • You have evidence about the rain conditions
  • You have evidence about how the conditions were different to those on average

In your own words, write a speech to the people of York, Shrewsbury or Lewes and explain the causes of the flooding. You may need to use a map of England to find out where these places are.

Complete your table to help your answer

In your speech include:

  • A copy of the flood plain map for each area
  • The average rainfall for each area
  • A calculation to show the difference between actual rainfall and the average
  • A calculation to show the anomaly for each location

Now SAVE your work.

Flooding extension exercise

This exercise gives you the chance to find out what the Flood Warning Codes mean and how many flood warnings have been issued over the past months.

Click on the link below:



Step 1:
Type in a town name in the Search box and find out when a Flood Warning was last issued. What type of flood warning was issued most recently?

Step 2: Follow the links through to ‘know your codes’ and ‘flood warming codes‘. This will open a page that describes what each of the warnings mean.

Copy the flood warning icons from the above web page into your Word document by following the instructions below:

  • Right-click on the icon and select ‘copy’ or ‘Copy Image’
  • Go into your Word document and position the cursor where you want to insert the icon
  • Right-click and select ‘paste’
  • Repeat these steps for the other three icons

In your own words, write a description of what each Flood Warning Code means.

Search the flood pages. Write a list of six actions that you should take when a Flood Warning is issued.

Now SAVE your work

You might find the following links useful.


Flooding Teachers Notes

Teaching objectives/Learning outcomes

At the end of this ICT lesson, students should be able to:

  • Identify and explain what a flood plain is
  • Use the internet to search for specific information on a local area
  • Apply maths to calculate changing meteorological conditions
  • Compare numerical geographical data and apply findings

The key aim of this lesson is for students to be able to define what a flood plain is and discover, using the internet, whether their local area is in a flood plain. Students will also look at the Flood Warning Codes and how these are delivered via the internet. Using information on average rainfall, students will look at the conditions that led to the flooding in October 2000. Estimated time for this task is either one or two lessons in the IT lab and can be divided broadly into two tasks: data gathering and data interpretation and representation using IT packages.

Web page reproduced with the kind permission of the Met Office

Extreme Weather (UK)

A series of downloadable lesson plans and teacher’s notes prepared on extreme weather for A level geography.

Produced by Rob Pugh

Work scheme on extreme weather