Key Stage 4 Maths Resources

Resources for 14-16 Year Old Students

Investigate How big is a raindrop collect data and analyse mode, mean and median, range, interquartile range and standard deviation etc. – with thanks to Stephen Lyon at the National STEM centre. Background information in an article in Weather: A low-cost experiment for determining raindrop size distribution.

A Met Office resource using maths/ stats skills to evaluate the weather of holiday destinations: Information For Teachers, Instructions For Students, Student Spreadsheet v1, Student Spreadsheet v2 and Teacher Spreadsheet

A maths/ geography resource from the Met Office for analysing weather data.

Another resource from the Met Office looking at the correlations between behaviour and the weather: instructions and worksheet.

Other recommended resources:

A wide range of animations from the Met Office suitable for geography and science topics.

Have a look at the Barometer – a regular podcast featuring weather and climate issues from the University of Manchester.

Further useful links.

AS/ A level Resources

Key Stage 3 Resources

Key Stage 4 Science Resources

Resources for 14-16 Year Old Students

Planetary radiation budget images for the EarthVenusMars with a dust storm and Mars without a dust storm

Establishing the radiation or energy budget of the Earth has been crucial to understanding climate change, but what do the radiation budgets of other planets in our solar system look like? Read about it here:

Climate Change

Watching the Earth – artificial satellites

Catalyst article on Cloud Seeding

Science or weather clubs.

Resources to 3D print the Central England Temperature record and use the models in subsequent STEM or geography clubs or lessons.

Met Office Design and Technology resources to build your own weather station (for the Resistant Materials GCSE topic): Anemometer Project – Student version, Rain Gauge Project – Student version, Thermometer Project – Student version and Thermometer Project – Teacher Example

Other recommended resources:

A wide range of animations from the Met Office suitable for geography and science topics.

Resources looking at change of state, latent heat, data handling and the Electromagnetic Spectrum from the NCAS/ DIAMET project.

Have a look at the Barometer – a regular podcast featuring weather and climate issues from the University of Manchester.

Further useful links.

AS/ A level Resources

Key Stage 3 Resources

Classroom Behaviour and the Weather

Behaviour and the weather

Overview

This project aims to extend students’ ideas and knowledge on correlation using the Weather Observations Website (WOW) website. It focuses on looking at the possible link between the weather and behaviour in schools

The project is more suited for KS4 pupils but a high ability KS3 class could probably cope with its content. It involves pupils drawing scatter graphs or using spreadsheets if they have access to computers.

The ideas here can be taught in a few lessons using these resources or they can be made into a mini project lasting longer.

Teachers can adapt the ideas to suit their needs and tasks can be extended.

For example pupils could design a survey to collect information on behaviour in their own school and gather local weather data using the WOW website. It has possible cross curricula links with maths.

Objectives

To develop knowledge and understanding on correlation between two variables.

To investigate if there is a link between behaviour in schools and the weather.

To use the WOW website to gather data on past weather observations.

To design a survey to collect information on behaviour in your school.

To gain experience in recording data in tables and spreadsheets.

To build on pupils’ ability to draw and interpret graphs.

Introduction

In this task you are going to analyse the weather data for a certain town and establish if there is a correlation between weather and behaviour. For instance, do pupils behave better or worse if it is windy?

The behaviour of the pupils was judged by their teachers over four weeks in the month of March and their behaviour was given a score by their teachers on a 1 to 8 scale.

Behaviour scale

The behaviour scale is determined by the teacher with 1 being excellent behaviour from the class and 8 being behaviour that is seen to be unacceptable from that class for that teacher.

 Behaviour no. Behaviour shown
 1 No interruptions from the class
 2 Very few interruptions to the lesson
 3 When they are completing their own work some pupils get distracted
 4 A few pupils start to distract each other and lose focus for longer periods
 5 Level of noise starts to increase and more off task behaviour is seen
 6 Pupils are distracted from their work and find it difficult to work
 7 Lots of interruptions to the lesson from a range of pupils both in their own work and when listening to the teacher
 8 Constant interruptions to the lesson, unable to work in the lesson

Worksheet exercise

Ask the students to use the worksheet to draw a graph. If time and resources permit they can gather their own data from WOW. Alternatively they can use the data from the completed worksheet.

Worksheet 1

Answers for Teachers

Extracting the weather data from WOW 

[the WOW website has changed a little since these instructions were written but it should be clear how to access the data]
 

1. Go to the WOW website address and search for station 3034 or St-Athan.

2. Click on the St-Athan weather station on the map.

3. Click on ‘View Full Observation’.

4. Click on the Graph tab.

5. Click on the ‘Show Filters’ tab and then the ‘Filter Options’ drop down box. Select ‘Air Temperature’ and ‘Wind Speed’, set the date range to the first week of observations, then click Update Graph.

5. To obtain the wind speed readings – go to the correct day and estimate the wind speed reading at 12:00. Fill this in the table of results.

The reading on 27/07/2020 at 12:00 is 9 mph. So write 9 mph for the wind speed.

6. Repeat this for each day of the week and then reset the date range for the next week. Do this by clicking the ‘Show Filters’ tab and then the ‘Filter Options’ drop down box, then ‘Update graph’.

Web page reproduced with permission from the Met Office.

Particulate Matter, ice, albedo and melting – Teacher’s Notes

In this experiment the students will look at the effect of Particulate matter or other substances that have landed on ice and test how this can speed up the melting of ice by affecting its albedo. Particulate Matter and aerosols are made up of a variety of pollutants, some of them enhancing and some counteracting the greenhouse effect when they are in the atmosphere. But once they land on snow or ice, they will promote the melting of these surfaces.

Chemistry Curriculum Links AQA GCSE

9.2.3. Properties and effects of atmospheric pollutants

Particulate Matter is a pollutant that absorbs at many different wavelengths, some act as greenhouse gases and others actually reflect more light than they absorb, leading to a reduction in the temperature of the atmosphere. When they (or Black Carbon in particular) deposit on snow and glaciers, they change the albedo (the reflectivity) of the snow surface. This controls the heat balance at the surface of snow and ice surfaces as the darker colour of the ice will lead to it melting faster.

 

Particulate Matter is solid particles that are so small that they float in the atmosphere and can be measured as a concentration in the atmosphere. They are formed from incomplete combustion of wood and fossil fuels. PM smaller than 2.5 microns (2.5 x 10-9 m), PM2.5 , is much smaller than the width of a human hair and can enter into our lungs and be carried into the blood system and cause damage to the brain and the cardiovascular system.

Uncertainties to do with the quantities of the different particles in the atmosphere (and the fact that particles enhance cloud formation) are part of the biggest current uncertainty in climate models.

Class Practical 

This experiment can be carried out in pairs or larger groups and takes about 20 minutes.

Follow the notes in the student worksheet, allowing more time to discuss what particulate matter is, what is albedo and how sunlight is absorbed differently by different coloured substances.

Discussion Questions

  1. Which ice cubes melted faster? Was it what they expected?
  2. Did all groups get similar results? Can we compare the melting rates as a % of original mass and see if they are similar between groups? What is the error in the melting rate of the 3 types of ice cubes?
  3. Does covering them with brown or black melt them faster?
  4. What are the possible errors in the experiment?

Application to the World’s Glaciers:

Glaciers around the world are more exposed to particulate matter now than they ever were before the industrial revolution and the increase in industry and cars over the last century. Covering snow and ice with a dark layer changes the albedo and they absorb more heat and melt quicker than the pure ice.

Particulates are tiny solid or liquid particles that are present in the atmosphere. They are sometimes termed aerosols when they float in the air. Examples are dust, spores and pollen, salt from sea spray, volcanic ash and smoke. Black carbon (elemental carbon (soot) or organic carbon) from incomplete combustion in the atmosphere can actually absorb incoming solar radiation and cool the Earth. However, when these particles land on ice, the absorption of radiation will enhance the ice´s melting.

References

Iain Stewart BBC black ice experiment

UN Environment programme, 2019: Glaciers are melting and air pollution is the cause

See bar chart of radiative forcing of various gases or particulates in Fig 14.4 Ramaswami et al., 2019

Ocean Acidification – Worksheet

Increased CO2 levels in the atmosphere are buffered by the oceans, as they absorb roughly 30 % of this CO2. The negative consequences of this are that the oceans become more acidic. The CO2 reacts with water and carbonate to form carbonic acid, reducing the available carbonate that shellfish, crabs and corals combine with calcium to make hard shells and skeletons.

Materials

Chemicals

Apparatus

Bicarbonate of soda (1/2 teaspoon)

2 x 500 ml Beakers

White vinegar (1 teaspoon)

Small plastic or paper cup (100 ml)

Indicator: Bromothymol blue

(Diluted with water: 8 ml bromothymol blue (0.04% aqueous) to 1 litre of water)

Masking tape

 

2 x Petri dishes or lid for large beakers

 

Safety glasses and lab coat

 

Teaspoon or 5 ml measuring cylinder

 

Two sheets of white paper

Method

  1. Pour 50 ml of the indicator solution into both beakers. 
  2. Add 1/2 teaspoon (2 grams) of bicarbonate of soda to the plastic cup.
  3. Tape one paper cup inside one beaker containing the indicator solution so that the top is about 1 cm below the top of the beaker. Make sure the bottom of the paper cup doesn´t touch the surface of the liquid in the plastic cup. The other beaker will be your control.
  4. Place both clear plastic cups onto a sheet of white paper and arrange another piece of white paper behind the cups as a backdrop (so you can see any colour change).
  5. Carefully add 1 teaspoon (5 ml) of white vinegar to the plastic cup containing the bicarbonate of soda. Be very careful not to spill any vinegar into the indicator solution. Immediately place a Petri dish over the top of each beaker.
  6. Position yourself so you are at eye level with the surface of the indicator solution, ready to see a colour change occurring.

Results

  1. What colour does the solution that contains the plastic cup change to?
  2. Vinegar (acetic acid) and bicarbonate of soda (Sodium bicarbonate) react to produce CO2 that is now present in the atmosphere of the large beaker, in contact with the indicator solution (the ocean). Some of the CO2 starts to absorb into the ocean, changing its pH.
  3.  A colour change from blue to yellow represents a reduction in pH. Is the solution (the ocean) becoming more acidic or more basic?

Application to the World’s Oceans

Corals and shellfish can be affected by ocean acidification, making it harder to create their shells, which will affect other fish up through the food web.

Corals and fish can be affected by slight changes in the temperature of the water and the next experiment also shows the effect of temperature increase on CO2 absorption, creating a positive feedback, a knock-on effect. 

Ocean CO2 Absorption – Worksheet

Does warm or cold water absorb CO2  better?

If the oceans are absorbing large quantities of water, and if we know the oceans are warming due to global warming, what is the effect of warmer oceans on CO2 absorption? Let´s check with this experiment that shows how much CO2 will dissolve in the water and how much will be in its gaseous form above the water.

Materials

Chemicals

Apparatus

Water

2 x 500 ml measuring cylinders

Effervescent fizz tablets (e.g. Alka Seltzer)

2 x Petri dishes that fit over the cylinders

Ice (optional)

Bowl or container of at least 5 litres

 

Stand and clamp to hold cylinders

 

Water heater

 

Funnel (optional)

Method

  1. Fill the basin half-full with cold  (or iced) water. Place the stand beside the basin.
  2. Fill the graduated cylinder to the brim with cold water and cover the top of the cylinder with the petri dish. Turn it upside down in the basin, making sure that no water spills out of the cylinder (so no air bubble forms). Remove the Petri dish when the cylinder is already underwater.
  3. Secure the graduated cylinder with the clamp to the stand and place the funnel in the mouth of the cylinder.
  4. Place an effervescent tablet carefully under the funnel. (Be sure your hands are dry so as to not set off the reaction prematurely).
  5. Observe the air space that develops at the top of the upside-down cylinder. Record the volume of the air space formed.
  6. Repeat the same procedure with warm water and record your results in the table. What happens to the air space when warm water is used? Is more or less air released than with cold water?
  7. Repeat the same experiment two or three times more with both cold and warm water.

Results table

 

Experiment number

WARM water (volume of air/ml)

Experiment number

COLD water (volume of air/ml)

1

 

1

 

2

 

2

 

3

 

3

 

4

 

4

 

AVERAGE volume

 

AVERAGE volume

 

 

Question: Does more CO2 escape from warm or cold water?

 

If more has escaped from the liquid, the water cannot absorb as much CO2.

Extension Question: With global warming and warmer oceans, will the oceans be able to absorb more or less CO2 than before?

What is the perfect pH of the oceans? Is it different depending on which ocean and whether it is in the deep ocean or the shallower coastal areas?

Ocean Acidification and CO2 Absorption – Teacher’s Notes

Increased CO2 levels in the atmosphere are buffered by the oceans, as they absorb roughly 30 % of this CO2. The negative consequences of this are that the oceans become more acidic. The CO2 reacts with water and carbonate to form carbonic acid, reducing the available carbonate that shellfish, crabs and corals combine with calcium to make hard shells and skeletons.

Curriculum Links: Core chemistry AQA GCSE

4.2.4 The pH scale

9.1.2 The Earth´s early atmosphere

9.2.3. Global climate change

Chemistry in the activity

Na2CO3 + 2 CH3COOH → 2 CH3COONa + CO2 + H2O (Bicarbonate of soda reacts with vinegar to form carbon dioxide)

In this experiment the students will initiate a reaction that produces CO2 in an enclosed water-air environment. The CO2 formed will be absorbed into the water, making it more acidic and changing the colour of the indicator. The experiment can be carried out in pairs and takes about 15 minutes. An additional experiment to test the solubility of CO2 in warm and cold water can be carried out afterwards, explaining how global warming can affect marine CO2 absorption.

Materials

  • Bicarbonate of soda (baking soda)
  • White vinegar
  • Bromothymol blue Indicator (diluted with water: 8 ml bromothymol blue (0.04% aqueous) to 1 litre of water)
  • 2 x 500 ml Beakers
  • Small plastic or paper cup (100 ml)
  • Masking tape
  • 2 x Petri dishes or lid for large beakers
  • Teaspoon or 5 ml measuring cylinder
  • Two sheets of white paper
  • Safety glasses and lab coat

See the student worksheets for the detailed preparation: Ocean acidification and CO2 Absorption

Application to the  World’s Oceans

The beaker is like an enclosed ocean-atmosphere and the CO2 from the reaction will equilibrate between the water and the air. Our oceans absorb more CO2 when the concentration in the atmosphere increases. But how much CO2 can they keep absorbing? Will they reach a saturation point?

Corals and shellfish are affected by ocean acidification, making it harder to create their shells, which will affect other fish up through the food web. Global warming caused by the increased CO2 effects the corals and fish as only slight changes in the temperature of the water can have effects throughout the ocean´s food chain. So there is a knock-on effect or a positive-feedback from the ocean heating and the ocean acidification.

If you want to illustrate more about the feedbacks and this double impact, the next experiment demonstrates the effect of a temperature increase on CO2 absorption, thus limiting the water´s capacity to absorb as much CO2.

CO2 Absorption in Water class practical

This experiment allows  students to determine how much CO2 dissolves in warm or cold water.

See the student worksheet for the detailed preparation.

Materials

  • Water
  • Effervescent fizz tablets
  • Ice (optional)
  • 2 x 500 ml measuring cylinders
  • 2 x Petri dishes that fit over the cylinders
  • Bowl or container (at least 5 litres)
  • Stand and clamp to hold cylinders
  • Water heater
  • Funnel

Application to the World’s Oceans:

More CO2 has escaped from the warm water, showing that it cannot absorb as much CO2. Warmer oceans will not be as effective buffers at removing CO2 from the atmosphere. However, this phenomenon does prevent these warmer oceans from being as acidic.

References

Particulate Matter, ice, albedo and melting – Worksheet

Have a look at these two glaciers, one has fresh snow over the glacier and the other is a dry glacier in summer with accumulated deposits of dust and Black Carbon from air pollution. Which one do you think is more vulnerable to melting? Does a bright white surface reflect more or less light than a darkened surface?

Silvretta Glacier with Fresh snow

Fresh clean snow on the Silvretta glacier,    Switzerland (Zoë Fleming)

Fox Glacier with dirty ice

Dirty ice on the Fox Glacier, New Zealand (Sylvia Knight)

Particulate Matter is solid particles that are so small that they float in the atmosphere. They are formed from incomplete combustion of wood and fossil fuels. When they are smaller than 2.5 microns (2.5 x 10-9 m, an eight the width of a human hair), this PM2.5 can enter into our lungs and be carried into the blood system and cause damage to the brain and the cardiovascular system.

When Particulate Matter (or Black Carbon, which is more or less soot or pure Carbon) settles on glaciers and snow it darkens the colour of the snow and hence changes the how much of the Sun’s light the snow reflects. In this experiment we will check to see whether dirty or clean ice melts faster.

Materials

 

Chemicals

Apparatus

3 ice cubes per group

3 bowls for placing ice cubes

Soot or Activated Carbon or burn a splint and gather the blackened combusted material

Spotlight

Soil or sand (as light coloured as possible)

Measuring scale

 

Spoon or forceps to move the ice cube between the bowl and the measuring scale

Method

  1. Take 3 ice cubes out of the freezer and place one in each bowl.
  2. Scatter soot over the ice cube in one bowl, covering it completely. Scatter the next ice cube with the soil. The last bowl will contain the control ice cube.
  3. Weigh each ice cube (using a spoon or forceps to place it on the scale).
  4. Shine the light bulb over the 3 bowls, trying to equally light/heat them all.
  5. After 5 minutes, remove each ice cube one at a time to weigh them.
  6. After 10 minutes, remove each ice cube one at a time to weigh them.
  7. If you have time to wait for the first ice cube to completely melt, note the time and note down how much was left of the other ice cubes (weigh them).

Results and Questions

  1. Which ice cubes melted faster?
  2. Does covering them with brown or black melt them faster?
  3. Thinking about a sunny day on snow, how do your eyes react to the sunlight? Does it seem like there is more light around or less than on a sunny day walking on bare soil? What about a sunny day on a boat? Do you think there is more or less light reflected back to your eyes than on land? The proportion of the Sun’s light which is reflected by a surface is called its albedo – a high albedo means a large proportion of the light is reflected and, therefore, only a small proportion is absorbed. 
  4. What about the difference between wearing white or black clothes on a sunny day- which one absorbs the sun rays and makes you feel warmer? Is that a small or large albedo?

Application for the world’s glaciers:

Glaciers around the world are more exposed to particulate matter now than they ever were before the industrial revolution. Covering them with a dark material changes the albedo. The darker the surface, the more of the Sun’s light is absorbed by the glacier, warming it and melting it. 

Particulates are tiny solid or liquid particles that are present in the atmosphere. They are sometimes termed aerosols as they float in the air. Black carbon (soot) is a particulate released from incomplete combustion. It absorbs the Sun’s light, which actually helps to cool the Earth. However, when it lands on ice, the absorption of radiation speeds up the ice´s melting as the light is absorbed by the dark colour and heats up the ice.

 

Social and political perspectives:

Knowing that air pollution that reaches glaciers is increasing their melting faster than what would happen from air temperature changes alone, what do you think we can do in terms of laws or behaviour change?

How can we reduce soot and Black Carbon reaching glaciers? Emission control of cars? Banning domestic wood-burning? Have you heard of smokeless coal that can be used in stoves in smoke-free zones? And pellet stoves, are there fewer emissions from these?

Note: You could carry out your own experiment if you are lucky enough to get snow. Prepare two neat snow blocks or two snow-balls of similar size and cover one with gravel or sand and leave the other clean. Watch which one melts first.

Orographic (relief) rainfall and the Foehn Effect

This case study or ‘mystery’ is taken from the afternoon of the 2nd September 2013. It focusses on Scotland and N. England. It can be used for two different purposes – either to identify orographic/ relief rain (use images 2-6 below), or to go on to identify a case study of the Foehn Effect (use all images).

We recommend that teachers present students in groups with a series of images, sequentially, to allow them to work out what the weather is doing and why. 

Expected Knowledge

Students should be

  • Familiar with a map of the UK
  • Know which way winds blow around a pressure system, and be able to identify fronts and pressure systems on a synoptic weather map
  • Know about the 3 main ways in which rain can form (frontal, convective or relief/ orographic rain)

Suggested Lesson Opener

Make a cloud in a bottle or watch the video.

Notes for Teachers 

Students can be helped, where appropriate to identify some of these points

Image 1

Image 1 – temperatures in degrees Centigrade at 15Z (1500GMT) (copyright Met Office)

The temperatures show that it is considerably warmer on the East side of Scotland than on the West. Temperatures are up to 9°C warmer on the East.

Why?

Image 2

Image 2 – a synoptic chart at 12Z (1200GMT) (copyright Met Office)

  • There are no weather fronts over the UK, although the whole country is in the warm sector of a low pressure system over Iceland.
  • There is a High Pressure system to the SW of the UK
  • Winds blow clockwise around a High pressure system, and along the isobars
  • The wind is therefore coming from the west (westerly winds) over Scotland
  • Alternatively, you could consider the winds blowing anticlockwise around the Low pressure system to the North – this also indicates that the wind direction over Scotland is from the west.
  • [We would normally associate this with Polar maritime/ returning Polar maritime air, but, in this case, if you follow the isoline back, the air has come from further south, so is Tropical maritime in nature.]
  • We would generally expect clear skies over most of the UK in this situation.

Image 3

Image 3 – wind speed in knots at 15Z (1500GMT) (copyright Met Office)

Image 4

Image 4 – satellite image at 15Z (1500GMT) : (c) EUMETSAT / Met Office

This is a satellite image from 1500Z (1500GMT) showing visible radiation ie light. The white areas are where the Sun’s light is being reflected from clouds.

There is cloud over the west coast of Scotland and N. England

You can also see the cloud associated with the warm front to the East of the UK, and the cold front to the west.

  • There is no front over Scotland, so the rain is not frontal rain.

Image 5

Image 5: Rainfall on 2nd September 2013 (copyright Met Office)

It is raining over the west coast of Scotland. Why?

  • There is no front there, so it is not frontal rain
  • Is it orographic rain or convective rain?

Image 6

A relief map of Scotland clearly shows the high ground on the East coast.

Synopsis

As the easterly winds blow in from the west, the air is forced to rise. As it rises, it cools until the rate of condensation is faster than the rate of evaporation. Cloud droplets form, which eventually become large enough to fall as rain.

Therefore, this rain is orographic or relief rain.

As the air descends again downwind of the mountains, the air warms and the cloud droplets evaporate.

As the cloud droplets form, they emit latent energy (heat) into the air around. This heat is remains in the air if the rain reaches the ground. This means that, downwind of the mountains when the air sinks, warms, and any remaining cloud droplets evaporate, there is more heat in the air than there was upwind of the mountains.

This is why temperatures were so much warmer on the east coast than on the west on this day!

Image 1

Image 2

Image 3

Image 4

Image 5

Orographic Rainfall in Scotland

Image 6

Scottish Orography

Global Atmospheric Circulation and Precipitation

  1. Visit https://svs.gsfc.nasa.gov/4285 and play the animation showing most currently available global precipitation data.
  2. Look at the map below. Circle any patterns of rainfall that you see.
Global precipitation map

3. What is the type of land is below these rainfall patterns? (Green is forest, brown is desert).                                                                                                                                                                                                                                    

4. In what latitude bands are these rainfall patterns?                                                                                                                                                            

Use these terms to fill in the blanks below for Questions 5-8: Hadley, cloud, humid, Sun, cloud, rainfall, low, ground, Ferrel, fronts, Equator, Hadley, poles, rainfall.

5. Rainfall occurs when ______ air cools down. Air cools when it rises, or when it moves away from the _______.

6. The Atmospheric Circulation is driven by the _____. In the Tropics, the Sun warms the _____ which in turn warms the air above. hot air rises, leading to _____ and _______. This drives the ________ cells.

7. Colder air sinks at the poleward edge of the _______ cells and over the __________. Sinking air has no _______ or __________.

8. In the _______ Cells, rainfall is mainly associated with ____ pressure systems (depressions). Rainfall is mainly on the ________.

9. Complete the following table (Look at the map for help):

 

Tropics

Sub Tropics

Poles

Skies

Clear/ Cloudy

Clear/ Cloudy

Clear/ Cloudy

Rain (or snow)-fall

Dry/ Wet

Dry/ Wet

Dry/ Wet

Pressure

High/ Low

High/ Low

High/ Low

10. Sketch what you think the Hadley Cell looks like in December and June by the images of the Earth below. Hint: the Equator and Tropics of Cancer and Capricorn are shown on the map.

Earth
Earth

Visit https://earth.nullschool.net/#current/wind/surface/level/overlay=precip_3hr/orthographic to see today’s rainfall patterns. Click on ‘Earth’ and then choose in the Overlay settings ‘3HPA’ to see the rainfall patterns together with surface wind speeds. Change in the settings the ‘Control’ to change the date and see rainfall patterns over time. Compare January and July rainfall patterns.

11. In the Tropics, how does the latitude of highest rainfall change between January and July?                                                                                                                                                                                                          ___________________________________                         

12. How does this relate to the sketches you drew above? ___________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Extension question: Why do you think you are asked to look at rainfall in January and July, rather than December and June? ___________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________