Green Living Association Cool our Planet, Category 3 Guidebook (Grades 6 to 8)

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2 About the Guidebook It's hard to think of many things powerful enough to disrupt life across our entire planet. We may take into consideration natural disasters like earthquakes, erupting volcanoes, terrorist attacks or catastrophic nuclear explosions, like the one that happened at the Chernoby (Ukraine in 1986), but even they do not affect the whole Earth. Global warming, which is a gradual rising of Earth's temperature, is different from all these, representing a scale of threat greater than anything humans have faced in recent history. Unless we tackle the problem soon, it could transform the planet we live on, making the climate (Earth's weather patterns) much more erratic, forcing many species into extinction, and making life much harder especially for people in developing countries. Due to the importance of the subject climate change is no longer only studied by scientists. Increasingly policy makers and citizens, including teachers, students and families are discussing and grappling with serious climate change issues facing the nations and the planet. Students are ready to learn and explore this complex topic and its importance in their world. They are energy consumers today as well as tomorrow s policy makers. They have the ability to continue on the same track or to help slow climate change. This guidebook is part of Cool our planet the last activity of our five yearly campaign Green Ways, with an aim to help students and their families develop the knowledge and skills needed to become informed participants in society s climate change discussions and to take action. The contents of each Guidebook are carefully developed in accordance with the capacities of the students in their respective grades and association of the teachers and supporters which could make those more meaningful and practical for the Green Angels. In addition to teaching facts, the suggestions and guidelines in the guidebooks are intended to provide students valuable life tools, like critical thinking, and encourage students to be active and responsible Pakistani citizens. Establishing a comprehensive project Cool our Planet for the students and their families had been a real challenge with its capacity to facilitate all Green Angels in their different educational grades, having diverse subjects and studying in varied educational institutes. There were many aspects to making this happen, but technical team has successfully accomplished the task. And implementation of this project was never possible without active participation by the dedicated administration of our Green Partner Schools and their Campuses. We thank you and believe our valuable association with the partner schools will bring a real positive change in the society. 2

3 Greenhouse Effect & Global Warming The Earth is wrapped in a blanket of air called the 'atmosphere', which is made up of several layers of gases. The sun is much hotter than the Earth and it gives off rays of heat (radiation) that travel through the atmosphere and reach the Earth. The rays of the sun warm the Earth, and heat from the Earth then travels back into the atmosphere. The gases in the atmosphere stop some of the heat from escaping into space. These gases are called greenhouse gases and the natural process between the sun, the atmosphere and the Earth is called the 'Greenhouse Effect', because it works the same way as a greenhouse. The windows of a greenhouse play the same role as the gases in the atmosphere, keeping some of the heat inside the greenhouse. THE NATURAL GREENHOUSE EFFECT The atmosphere has a number of gases, often in tiny amounts, which trap the heat given out by the Earth. To make sure that the Earth's temperature remains constant, the balance of these gases in the atmosphere must not be upset. 3

4 The GREENHOUSE GASES are very important and are mainly: water vapour occurs naturally in the atmosphere. carbon dioxide produced naturally when people and animals breathe. Plants and trees absorb carbon dioxide to live. Volcanoes also produce this gas. Carbon dioxide is not the same as carbon monoxide methane comes from cattle as they digest their food. The gas also comes from fields where rice is grown in paddy fields. nitrous oxide when plants die and rot, nitrous oxide is produced. ozone occurs naturally in the atmosphere. THE ENHANCED GREENHOUSE EFFECT Some of the activities of man also produce greenhouse gases. These gases keep increasing the atmospheric temperature. The balance of the greenhouse gases changes and this has effects on the whole of the planet. Burning fossil fuels - coal, oil and natural gas - releases carbon dioxide into the atmosphere. Cutting down and burning trees also produces a lot of carbon dioxide. A group of greenhouse gases called the chlorofluorocarbons, - which are usually called CFCs, because the other word is much too long! - have been used in aerosols, such as hairspray cans, fridges and in making foam plastics. They are found in small amounts in the atmosphere. They are 4

5 dangerous greenhouse gases because small amounts can trap large amounts of heat. Because there are more and more greenhouse gases in the atmosphere, more heat is trapped which makes the Earth warmer. This is known as GLOBAL WARMING. A lot of scientists agree that man's activities are making the natural greenhouse effect stronger. If we carry on polluting the atmosphere with greenhouse gases, it will have very dangerous effects on the Earth. THE EFFECTS With more heat trapped on Earth, the planet will become warmer, which means the weather all over Earth will change. For example, summers will get hotter, and winters too. This will have dangerous effects on the living things, because the conditions we are living in are perfect for life, and a large rise in temperature could be terrible for us and for any other living thing on Earth. At the moment, it is difficult for scientists to say how big the changes will be and where the worse effects will occur. The Weather In the countries like Pakistan, winter and summer temperatures will increase and the weather will be warmer. In winter it may also rain more but in summer it may become drier. In other parts of the world, the effects will be different, some places will become drier and others will be wetter. Although most areas will be warmer, some areas will become cooler. There may be many storms, floods and drought, but we do not know which areas of the world will be more affected. 5

6 All over the world, these weather changes will affect the kind of crop that can be grown. Plants, animals and even people may find it difficult to survive in different conditions. Sea Levels Higher temperatures will make the water of the seas and oceans expand. Ice melting in the glaciers (Pakistan s northern tops, Antarctic and Greenland) will flow into the sea. All over the world, sea levels may rise, perhaps by as much as 20 to 40 cm, by the beginning of the next century. Higher sea levels will threaten the low-lying coastal areas of the world, such as the Netherlands, Japan and Bangladesh. Throughout the world, millions of people and areas of land will be at danger from flooding. Many people will have to leave their homes and large areas of farmland will be ruined because of floods. Farming The changes in the weather will affect the types of crops grown in different parts of the world. Some crops, such as wheat and rice grow better in higher temperatures, but other plants, such as maize and sugarcane do not. Changes in the amount of rainfall will also affect how many plants grow. The effect of a change in the weather on plant growth may lead to some countries not having enough food. Brazil, parts of Africa, south-east Asia and China will be affected the most and many people could suffer from hunger. Water Everywhere in the world, there is a big demand for water and in many regions, such as the Sahara in Africa, there is not enough water for the people. Changes in the weather will bring more rain in 6

7 some countries, but others will have less rain. IN DANGER! Plants & Animals It has taken million of years for life to become used to the conditions on Earth. As weather and temperature changes, the homes of plants and animals will be affected all over the world. For example, polar bears and seals, will have to find new land for hunting and living, if the ice in the Arctic melts. Many animals and plants may not be able to cope with these changes and could die. This could cause the loss of some animal and plant species in certain areas of the world or everywhere on Earth. People Acid Rain The changes in climate will affect everyone, but some populations will be at greater risk. For example, countries whose coastal regions have a large population, such as Egypt and China, may see whole populations move inland to avoid flood risk areas. The effect on people will depend on how well we can adapt to the changes and how much we can do to reduce climate change in the world. Rain is very important for life. All living things need water to live, even people. Rain brings us the water we need. But in many places in the world even where you live, rain has become a menace. Because of pollution in the air, acid gases from factories, cars and homes, the rain is becoming dangerous for the life of every living creature. This rain is known as 'acid rain'. 7

8 WHAT IS ACID RAIN? Acid gases are produced when fossil fuels like coal and oil are burned in power stations, factories and in our own homes. Most of these acid gases are blown into the sky, and when they mix with the clouds it can cause rain - or snow, sleet, fog, mist or hail - to become more acidic. The opposites of acid are alkalis; for example, toothpaste and baking powder are both alkalis. Strong alkalis can also be dangerous, such as ammonia and bleach. Lemon juice, vinegar and cola are all acidic. Rain is naturally acidic, but acid gases make it even more acidic, sometimes as acid as lemon! Nature can also produce acid gases, such as volcanoes. When they erupt, the smoke that comes out of the crater is also full of acid gases. HOW DO WE MEASURE ACIDITY? There is a special scale called the ph scale that measures the strength of acids and alkalis. A low ph number means something is acid. A high number means something is alkali. And something in the middle is called neutral. Acidity can be tested using litmus paper. Usually rain is a little acidic, and has ph of about 5.5, if the ph of rainfall is less than 5.5, then the rain is probably polluted by acid gases. Acids turn litmus paper red, and alkalis turn it blue. With a special paper called universal indicator, you can test levels of acidity. 8

9 WHAT ARE THE MAIN GASES THAT CAUSE ACID RAIN? When we burn fuels, chemicals called 'sulphur' and 'nitrogen' are released into the air. Once in the air, they mix with water in the air - rain, snow, etc - and are transformed into different chemicals called 'sulphur dioxide' and 'nitrogen oxides', which can be very dangerous for plants, animals and people. Most of the 'sulphur' comes from power stations, which make electricity, and also from volcanoes. Most of the 'nitrogen oxides' come from car and truck exhausts. We call 'air pollution' the bad gases that we produce and release in the air. 'Sulphur dioxide' and 'nitrogen oxides' are the most important causes of acid rain. A PROBLEM ALL OVER THE WORLD Air pollution (say: po-loo-shun) can be carried over long distances. When acid gases are released, they go high up in the sky, and then they are pushed by strong winds towards other countries. The acid rain in Sweden is caused by air pollution in Britain and other countries of Europe. The pollution produced in Japan ends up mostly in the countries of Southeast Asia such as Indonesia and Thailand and so on. HOW BAD IS ACID RAIN? When rain is acidic, it affects what it falls on: trees, lakes, buildings and farmland. Sometimes rain is not very acidic and does not cause a lot of problems, but when it is acidic, it can be very harmful to the environment. 9

10 TREES AND PLANTS Acid rain can have terrible effects on a forest. The acid takes away important minerals from the leaves and the soil. Minerals are like vitamins for trees and plants. Without them, trees and plants cannot grow properly. They lose their leaves and become very weak. They are no longer strong enough to fight against illnesses and frost. They become very ill and can even die. Some soils are alkaline, when acid rain falls on them the acid becomes neutral. Plants and trees living on these soils are not in any big danger. LAKES AND WATER LIFE Acid rain has a terrible effect on water life. Even if the acid rain does not fall straight into the lake, for example, it may enter from rivers and streams. Some of the life in the lake such as fish and plants may end up dying, because they cannot survive in acidic lakes. Thousands of lakes in Europe and Asia have no more life in them. They have received so much acid rain for so many years, because of the winds pushing the acid gases, that nothing can survive. You can recognise a lake dead from acid rain by its clean and crystal clear water. But they look clean because there is very little living in them anymore. Tiny plants and animals are mostly unable to survive. OUR HEALTH Particulates - very small particles of debris found in some of the air pollution - are one of the main causes of health problems. In towns and cities, these are released mainly by diesel engines from cars and trucks. 10

11 When we breathe in polluted air, these very fine particulates can easily enter our body, where they can cause breathing problems, and over time even cause cancer. Water we drink from taps can be contaminated by acid rain, which can damage our health. BUILDINGS Acid rain can also ruin buildings because the acid eats into metal and stone. It also damages stained glass and plastics. Some types of building materials are softer than others, and it is the softer ones which are most affected by acid rain. Sandstone and limestone are examples of stone which are fairly soft and are damaged easily. Granite is an example of a harder stone that can resist the effects of acid rain. In many places in the world, ancient and famous buildings and monuments are affected by acid rain. For example, one of the world s historical treasures, Taj Mahal in Agra (India), needs restoration because of acid rain damage. Buildings are naturally eroded by rain, wind, frost and the sun, but when acidic gases are present, it speeds up the erosion. Air Quality You need to breathe to stay alive. But how clean is the air you breathe? If you breathe dirty air, you are more likely to develop health problems and become ill. Plants and animals need clean air too. A lot of the things that make our lives more comfortable such as cars, electricity and heating, create bad gases which make the air dirty. The problem of air pollution started with the burning of coal in homes and factories. Dirty air is called 'polluted air'. 11

12 'Air pollution' is what we say to describe all bad gases and particles in the air that we breathe and that are dangerous for us. But do not worry! Not all gases are bad! WHY IS BREATHING SO IMPORTANT? Take a few deep breaths. Can you feel your rib cage moving in and out? This opens up your lungs so that air is sucked in. In the lungs, a gas called oxygen passes from the air into your blood. The oxygen is carried in the blood all round your body. You need oxygen so that you can use the energy in the food you eat. It is the oxygen in the air that helps keep you alive. BACK TO THE PAST 500 years ago in the most developing countries the burning of coal was increasing. Coal was used in factories and also used to heat homes. Coal, when burnt makes a lot of smoke, which makes the air very dirty. About 200 years ago, the Industrial Revolution began in Europe and America. Factories were built, and even more coal was burnt. Air pollution was becoming a really big problem, especially when the weather was foggy. With foggy conditions and light winds the smoke or air pollution covered the whole cities, and would not move. Smoke and fog together create smog. 12

13 Smog was a big problem in the winter. Because of the cold weather, more coal was burnt to warm houses and this made more smoke. When smog was stuck over a city, it became really hard to breathe and see clearly. In 1952, the Great London Smog occurred and more than 4000 people died because of the smog! Then new laws were passed in the developed countries so that such kind of incident would not happen again. These laws are called the 'Clean Air Acts'. These laws were made so that air would become cleaner. The laws encouraged people to use less coal or use cleaner coal in their homes and switch to other fuels such as gas. Factories started using tall chimneys so that the smoke would go high up in the sky and no longer cover cities. The new factories were built outside cities in the countryside. Gradually smog occurred less often and the air became cleaner. WHAT IS TODAY'S AIR POLLUTION LIKE? Have you ever noticed that the air in a city smells different from air in the village? One of the reasons is that exhausts from vehicles give off fumes, or gases, which can poison you. Today, when we think of air pollution, we should think of transport, especially cars. Today there are millions of vehicles on the roads in Pakistan, and most of them are cars! The fuel they use - petrol and diesel - releases a lot of pollution in the air. The car exhausts eject a lot of bad gases, which create air pollution. These gases can be very dangerous for children. Although the fuels are becoming cleaner, it will not be making that much difference because each year there are more and more cars on the roads. 13

14 There is less pollution from coal, but our changing lifestyles create greater air pollution. Today, air pollution has not really fallen, because new bad gases are released in the air, and there are a lot of them. Transport is not the only reason why we have air pollution. Factories also release bad gases in the air, even with the increasing awareness, it still causes a lot of air pollution. This air pollution that they make is the main cause of rising health issues in the society. WHAT ARE THESE BAD GASES? Gases from vehicles: Carbon monoxide Carbon monoxide is a gas that pollutes the air, and is mainly released by cars and other vehicles. It has no colour or smell. Nitrogen oxides Nitrogen oxides are emitted from vehicles, like cars and trucks. During rush hour periods, a lot more is released in the air. Nitrogen oxides are also emitted from power stations. These gases also make acid rain. Hydrocarbons Hydrocarbons are produced when petrol is not fully burnt. They are one of the causes of modern-day smog. Particulates Particulates are very small particles, like soot, dust and fumes that are released in the air. They are caused by vehicles, factories and smoke from homes burning coal for heating. Gases from factories: Nitrogen Oxides (see above) Sulphur dioxide Sulphur dioxide has no colour. Most of it is released by power stations. It causes acid rain when mixing with water in the air. 14

15 AIR POLLUTION INSIDE HOMES We spend a large part of our lives at home and it does not often cross our mind that the air we are breathing may be polluted. Pollution inside homes is called 'indoor air pollution'. Indoor air pollution is usually very low. But a lot of things can increase it. Fresh paint is a cause of indoor air pollution and so is the burning of fuels such as coal and gas, in heaters, stoves and ovens. But one of the main causes of indoor air pollution is smoking. Smoking cigarettes and tobacco can be very dangerous for health. The poison in the smoke can cause heart problems, lung cancer and other lung diseases. Smoking has really bad effects on all vital organs in our body which function to maintain our life. Cigarette smoke is dangerous for people smoking but also for those who do not! Breathing in air, which contains other people's smoke, can cause you the same health problems, for example lung cancer. To reduce 'indoor air pollution', make sure the room is well ventilated while painting. Try ventilating your home often, you can open windows or use a fan. And if your parents or relatives smoke, ask them to smoke outside. And best of all NEVER START SMOKING!!! 15

16 Ozone Hole The Earth is wrapped in a blanket of air called the 'atmosphere', which is made up of several layers. About kilometres above the Earth is a layer of gas called ozone, which is a form of oxygen. Ozone is produced naturally in the atmosphere. WHY DO WE HAVE AN OZONE LAYER? The ozone layer is very important because it stops too many of the sun's 'ultra-violet rays' (UV rays) getting through to the Earth - these are the rays that cause our skin to tan. Too much UV can cause skin cancer and will also harm all plants and animals. Life on Earth could not exist without the protective shield of the ozone layer. WHAT IS THE OZONE HOLE? Every spring, a hole as big as China develops in the ozone layer over Antarctica, in the South Pole. A smaller hole develops each year over the Arctic, at the North Pole. And there are signs that the ozone layer is getting thinner all over the planet. Scientists have discovered that the ozone hole over Antarctica started in 1979, and that the ozone layer generally started to get thin in the early 1980s. The loss of the ozone layer occurs when more ozone is being destroyed than nature is creating. WHAT CAUSES THE OZONE HOLE? One group of gases is particularly likely to damage the ozone layer. These gases are called CFCs, Chloro-Fluoro-Carbons. CFCs are used in some spray cans to force the contents out of the can. 16

17 They are also used in refrigerators, air conditioning systems and some fire extinguishers. They are used because they are not poisonous and do not catch fire. Most countries have now stopped using new CFCs that can be released into the atmosphere, but many scientists believe we must stop using old ones as well. THE OZONE HOLE AND OUR HEALTH The ozone layer is like a sunscreen, and a thinning of it would mean that more ultra-violet rays would be reaching us. Too many UV rays would cause more sunburn, and because sunburn causes skin cancer, this too would increase deaths. These UV rays are also dangerous for our eyes and could cause an increase in people becoming blind. That is why sun cream and sunglasses are very important. THE OZONE HOLE ON ANIMALS AND PLANTS UV rays can go through water and end up killing small water animals or plants, called 'plankton' which form the base of the food chain in oceans and seas. Whales and other fishes have plankton as their main food, and if plankton die because of these UV rays, whales will start dying too, because they will not have anything to eat. Large amounts of UV rays could damage all green plants. If the ozone layer keeps getting thinner, there could be fewer and fewer plants on Earth, then there would be less food in the whole world. THE TWO-FACED OZONE GAS Ozone found between 19 and 30 kilometres high in the atmosphere is one of the reasons why we are alive on Earth. 17

18 But when the gas ozone is found lower down where we can breathe it in, it becomes very dangerous for our health. This ozone is caused by a reaction between air pollution and sunlight and can cause modern-day smog. This is different to the smog that formed in the early 20th century from smoke and fog. Your role in making things better There are many things we can do to help reduce air pollution and global warming. Use buses and trains instead of cars, as they can carry a lot more people in one journey. This cuts down the amount of pollution produced. Walking or cycling whenever you can, will be even better, as it does not create any pollution. It will also be good for your body, as regular exercise will keep you fit and healthy. If your parents must use the car, ask them to avoid using it for very short journeys if possible, as this creates unnecessary pollution. Try to encourage them to share their journeys with other people, for example when they go to work or go shopping. Also encourage them to drive more slowly as this produces less pollution and less carbon dioxide. Energy is produced to generate electricity and to keep us cool and warm. Most energy is produced by the burning of fossil fuels, like coal, oil and gas, which release carbon dioxide, a greenhouse gas. Fuel burnt in our cars also releases carbon dioxide. As an individual, you do not have a lot of control on how your energy is produced. However, you can control the way in which you use that energy. Using less energy means less of it needs to be produced. 18

19 So less carbon dioxide is released into the atmosphere. We can also help prevent pollution from our own homes which may contribute to acid rain and poor air quality, and increases emissions of carbon dioxide in the atmosphere. Turning off lights when they are not needed and not wasting electricity will reduce the demand for energy. Less electricity will need to be produced and so less coal, oil and gas will have to be burnt in power stations, which means less air pollution and less carbon dioxide! Pollution formed indoors can be reduced by ensuring that all gas appliances are working correctly. Good ventilation will improve indoor air quality by dispersing biological pollutants like dust mite, and other pollutants such as cigarette smoke. Most of the rubbish we throw away can be recycled, such as glass bottles and jars, steel and aluminium cans, plastic bottles and waste paper. Recycling used materials uses less energy than making new ones. Composting fruit and vegetable waste reduces the amount of rubbish buried at rubbish dumps. About half of the greenhouse effect is caused by our use of energy, especially from fossil fuels. Other sources of energy could be used which do not emit carbon dioxide, e.g. wind power, solar (sun power) and wave power. In the home and at school, we must learn to use energy efficiently and not waste it. What you can do more 1. Conserve energy in your everyday life. Making simple choices to save energy may help avoid the serious consequences of global warming. For example: Turn off the lights. Close doors immediately so cooling or heat does not escape. Take short showers. Walk or bike if you can (instead of having your parents drive you). Turn off your computer when not in use (don't leave it on just to keep it active). 19

20 2. Convince the people around you to save energy. Now, you have to be careful here because people don't like to be told what to do, so persuasion is the important part. Your parents would be perfect subjects for persuasion, but do it with love and humour. Here are some suggestions that you can provide for your family and friends. Replace incandescent with fluorescent lights. (This saves a lot of money!) Ask your parents not to leave the car running needlessly, for example, when waiting to pick you up at school. Recycle (this saves energy in manufacturing). Run the dishwasher and other appliances on energy saver mode. Keep your room at 26 C or more. And make sure cooling goes off at night and when everyone is away. Start a conservation club at school to raise awareness. Get your fellow students and teachers on board to have the school reduce energy consumption. In fact, not knowing is one of the problems. Global warming is a significant risk to society. On the one hand, we do not know exactly what will happen. On the other, we realise that what could happen could be serious. And these consequences could affect different parts of the world in different ways. 3. Keep learning. These ideas all involve conservation. While that's important, what's more important is finding and implementing sources of energy that do not pollute the environment. Who is going to do that? It can be you! So the third and most important thing you can do is get the best education you can get, so that you can be a responsible citizen and continue making good decisions. Maybe you will help find scientific, technological, economic, or political solutions to the present situation in making our beautiful planet cooler and our beloved homeland Pakistan greener and cleaner. 20

21 Copy rights Information in this guidebook can be shared/reproduced only with clearly stated attribution to Green Living Association (GLA) All Rights Reserved 21