Climate Change Resource
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≥ Climate Change Resource Climate Change ‘We have a message here to tell these countries that you are causing aggression to us by causing global warming’ Yoweri Museveni, President of Uganda, 2007 Active Citizenship Department, Concern Worldwide Cover pic: Uganda Nr. Mukono A girl uses a leaf for shelter during a rain storm. Photo: Caroline Penn/ Panos Pictures Inside Cover pic: Two Gabbra woman llo Jarso and Gonche Salesa make their way through a dust-storm as they walk back into Kalacha. Photo: Gideon Mendel, Kenya. Written by: Fran Brady Edited by: Michael Doorly Contents Introduction 02 Objectives 02 Disturbing Facts 02 Section One Understanding Climate 03 Definitions of climate 03 What human activities have contributed to global warming and climate change? 06 Section Two Consequences of Climate Change 11 What are the consequences of Climate Change? 11 Realities of Climate Change in the Developing World 16 Section Three International Agreements. What can be done? 21 International Agreements on Climate Change 21 What can be done? 23 Web links - further information 27 ISBN 978-0-9524506-4-1 Introduction The impact of uncurbed global warming is already devastating the lives of millions of people across the globe, particularly in those countries that have the fewest resources to cope. The floods affecting 17 countries in Africa in September 2007 were said to have been the worst in decades, with over 250 people killed and 1.5 million people displaced from their homes and villages. For millions of poor people around the world the devastating effects of climate change are now a fact of life, and are already undermining the progress intended under the internationally agreed Millennium Development Goals. Those who are least responsible for creating global warming it seems, will be the very ones to suffer most from its effects. OBJECTIVES This resource has been written for Second Level Geography teachers and their students. • For the Leaving Certificate Curriculum, it aims to complement the Elective Unit: Trade and the Environment and Optional Units: Global Interdependence and The Atmosphere/Ocean Environment. • This resource is also relevant to the Human Habitat Section on the Junior Certificate Syllabus and to the Study: Acting Locally – Thinking Globally in Section B Environment of the CSPE Programme. • Case studies of the impacts of climate change in the developing world are included. DISTURBING FACTS Crop yields in Sub-Saharan In 2007 the worst flooding Ocean temperatures have Africa are projected to fall in 50 years in Hunan Province increased from the surface by 20% because of global in China caused a plague of as far down as 3000m. warming 2 billion mice. www.un.org www.irishtimes.com Vulnerable areas have seen a 65-fold increase in the In India the Gangotri glacier number of people affected by In 2005 there were 28 tropical is receding at an average rate disasters in the past 30 years. storms - the highest number of 23 meters per year. www.neweconomics.org since record keeping began nationalgeographic.com about 150 years ago - and 15 hurricanes including 7 major Of the 600,000 or so people hurricanes. The Ward Hunt Ice Shelf, who died in extreme weather www.pewclimate.org which had been in place for events during the 1990s 99% 3,000 years is now breaking were in poor countries. into pieces. www.who.int Rising temperatures in Alaska www.ndrc.org has spurred the spruce bark beetle to breed faster. From In Bangladesh 20 million people 1993 to 2003, the beetle Worldwide deforestation will become environmental chewed up 3.4 million acres accounts for up to 25% of refugees as a result of of Alaskan forest. global emissions of heat climate change www.ndrc.org trapping gases. www.timesonline.co.uk www.independent.co.uk Resource Pack ≥ 2/3 Climate Change ≥ Section One Understanding Climate In order to understand climate The atmosphere is comprised mainly of: change it is important to understand • Nitrogen (N2, 78.1% volume mixing ratio); the nature of climate. Climate can • Oxygen (O2, 20.9% volume mixing ratio); be defined as the meteorological • Argon (Ar, 0.93% volume mixing ratio). conditions that characteristically prevail in a particular region. Altitude (km) Weather, however, is the state of the atmosphere 100 over a short period of time such as a day, a week or a month. Climatic elements include precipitation, 90 temperature, humidity, sunshine, wind velocity, fog, frost, hailstorms and other measures of weather. 80 In short: 70 • Climate is the average weather, usually taken over a 30 year time period, for a particular region; 60 • Continual changes in climatic elements occur 50 within the lowest layer of the atmosphere (the troposphere); 40 • Climate determines the productivity of food and 30 fibre, fisheries and water resources; 20 • Earth’s global climate depends on the amount of energy received from the sun and the amount 10 of energy trapped at its surface by the greenhouse gases; 0 -100 60 20 0 20 • Earth’s regional climates are highly variable and Temperature (ºC) this ensures the diversity of ecosystems. Source: www.physicalgeography.net The atmosphere In the atmosphere, both oxygen and nitrogen exist in their most stable elemental states. Atmospheric An envelope of gases called the atmosphere oxygen exists as a molecule of two oxygen atoms surrounds the earth. These gases extend to a bonded together, O2, and atmospheric nitrogen height of 1,000 km. The Earth’s atmosphere has exists as a molecule of two nitrogen atoms bonded four main layers: the troposphere, the stratosphere, together, N2. These gases do not interact with the the mesosphere and the thermosphere. The layers infrared radiation emitted by the Earth. are distinguished by different temperatures and densities. Through the effects of gravity, 75% of the There are heat-trapping gases, known as greenhouse total mass of the atmosphere is in the troposphere. gases, which absorb infrared light and prevent it The depth of the troposphere varies from about 8 to being re-radiated into outer space. 16 kilometres. Without the atmosphere, there would be no life on earth. Greenhouse gases Greenhouse effect These greenhouse gasses include: The greenhouse effect is a necessary phenomenon that keeps all of earth's heat from escaping to the • carbon dioxide (CO2) which is exhaled by outer atmosphere. Without the natural greenhouse living organisms and utilised by plants during effect life on earth would be difficult to sustain. photosynthesis. The main human-related sources of carbon dioxide (CO2) include the burning Due to increased greenhouse gases however the of fossil fuels; deforestation; forest fires; the atmosphere is absorbing more infrared energy than destruction of peatlands; and the manufacture it re-radiates to space, resulting in a net warming of cement; of the earth-atmosphere system. It is this excess heating which is causing global warming and climate • methane (CH4), a carbon-based gas, which is change. During the last 150 years, the atmospheric released from ruminants such as cattle, sheep, concentration of carbon dioxide has increased by goats and buffalo. Methane is also released 31% and the level of atmospheric methane has from the breakdown of plant material under wet risen by 151%. conditions. Other sources of methane include rice cultivation, biomass burning, fossil fuel combustion and disposal of domestic refuse in landfill sites; • nitrous oxide (N2O). The main human-related sources of nitrous oxide (N2O) are fertiliser use; livestock management; biomass burning and Carbon dioxide, methane, and industrial activities. There is very little N2O in the atmosphere (about 0.000003%), but due mostly nitrous oxide have different to human activity, it is actually increasing by about global warming potential. 0.3 % every year. N2O is extremely efficient at warming up the atmosphere. In fact, one molecule GWP: an index used to translate the level of N2O has 200 to 300 times the greenhouse of emissions of various gases into a warming effect of CO2, the primary greenhouse gas; common measure in order to compare the • chlorofluorocarbons (CFCs) are halocarbons used relative impact on the environment. GWPs in air conditioners and many industrial processes. are calculated as the ratio to one tonne CFCs deplete the ozone as well as act as of CO2. Global warming potentials (GWPs) greenhouse gases. are based on the heat-absorbing ability of each gas relative to that of carbon dioxide (CO2). CO CH N O HFC-23 Greenhouse Gas 2 4 2 carbon dioxide methane nitrous oxide hydrofluoro-carbon-23 Global Warming Potential (GWP) 1 21 310 11,700 Resource Pack ≥ 4/5 Climate Change The Greenhouse effect 1. Solar radiation passes through the clear atmosphere. The Greenhouse Effect 2. The ground absorbs the heat, Some of the infrared radiation passes through the and reflects some of it back into the air. atmosphere but most is absorbed and re-emitted in all directions by greenhouse gas molecules and Solar radiation powers clouds. The effect of this is to warm the Earth’s the climate system. surface and the lower atmosphere. 3. Some of the infrared radiation passes through the atmosphere and is lost in space. 4. Some of it is absorbed and re-emitted Some solar radiation by the greenhouse gas molecules. In is reflected by the Earth and the atmosphere this way, the atmosphere acts like a Infrared radiation is emitted big blanket over the earth, holding in from the Earth’s surface. the warmth and reflecting it back to earth. About half of the solar radiation is 5. The effect is the warming of the earth's absorbed by the Earth’s surface and warms it. surface and the troposphere. began in 1766, resulting in floods that killed 6. The earth’s surface gains more heat The Intergovernmental Panel on Climate Change nine people.