How are people changing the climate? Read more Unit2: What will the future be like? In the Basics-section you will find links to the Read more-section. Follow those links if you want to explore an issue in more depth (rather than reading this Read more-section from beginning to end). In this unit you can read about: - The Intergovernmental Panel on Climate Change (IPCC) - Future emissions and climate change - Changes in different parts of the world - Vulnerability and adaptation This unit also has a worksheet. Part 1: Parts of the World Changes in different parts of the world What are the impacts of climate change over the next hundred years expected to look like in different parts of the world? Read here what the IPCC has to say. Click the map to read about possible consequences of climate changes in different parts of the world. Africa A weak economy makes adaptation to climate change difficult. Vulnerability is high, mainly because people depend so heavily on agriculture and don't have the benefit of irrigation. ESPERE Climate Encyclopaedia www.espere.net - People changing the Climate More - page 1
1. Even drier: Global warming could make deserts spread in parts of Africa. Photo: NOAA photo library. More frequent drought, flooding and other extreme weather events will have a negative effect on peoples access to food, water and health care and will slow down development in Africa. Sea-level rise will result in more frequent flooding and more coastal erosion. Several countries in Africa are especially vulnerable to this. Grain yield is expected to drop leading to food shortages, especially in countries which import little food. The rivers in the northern and southern countries in Africa will have reduced flows of water. Insects that carry diseases will expand their habitats. This will lead to an increase in diseases transmitted in this fashion (malaria, for example). Desertification (land turning into desert) will occur more quickly because of reduced rainfall, especially in Southern, North, and West Africa. Many plant and animal species will become extinct, which in turn will have a negative effect on agriculture and tourism. Asia There is a large gap between Asian countries when it comes to vulnerability to climate change. Poor countries are very vulnerable and will have a difficult time adapting, whilst the rich countries will adapt much more easily. 2. Tropical Cyclone Dina northeast of Mauritius and Reunion Islands in the Indian Ocean. This image was captured on January 20, 2002. Photo: NASA. Extreme events such as flood, drought, forest fires and tropical cyclones may increase in the warmest parts of Asia. Sea-level rise and the increased intensity of tropical cyclones may make the homelands of tens of millions of people living in the coastal areas in temperate and tropical Asia uninhabitable. Sealevel rise will also threaten coastal eco-systems, especially mangrove trees and coral reefs. Production in agriculture and fishing in tropical areas will be reduced, while agriculture in northern areas will be increased. There will be less access to water in several places in the south, while there will be improved access in many places in the north. There will be a greater spread of disease because of the increase in disease-carrying insects and more extreme heat. Energy demand will increase. Some regions will experience a great loss in tourism. Faster extinction of animal and plant species will become more likely. ESPERE Climate Encyclopaedia www.espere.net - People changing the Climate More - page 2
Australia and New Zealand In general, Australia and New Zealand have a high adaptive capacity and are thus not very vulnerable. The exception is the Aboriginal population. More frequent drought will make access to water a more important issue and increase the likelihood of forest fires. Some species that are specially adapted to particular climates will become threatened and face extinction. This includes the coral reefs. The initial impacts of climate change are expected to have positive effects on agriculture but if the trend continues, the negative effects will eventually outweigh the positive effects for certain types of agriculture and in certain areas. Increased frequency and intensity of tropical cyclones will result in increased risk of damage to human life, property, and ecosystems through more flooding, storm surges and wind. 3. Forest fires could become more frequent in areas that get hotter and drier. Photo: Corel Gallery. Europe Europe generally has a relatively high capacity to adapt. Southern Europe and areas around the Arctic region are somewhat more vulnerable than other parts of Europe. There will be more precipitation in the north, and less in the south. Southern regions will therefore become more vulnerable to drought. Biological zones tree lines, for example will move northward and upward. Some species will lose their niches and could thus face extinction. The danger of rivers flooding will increase in over large areas of Europe. Coastal regions will be more vulnerable to flood and erosion and this will damage coastal settlements and agriculture. Glaciers in alpine landscapes will be significantly reduced. Permafrost (ground that is frozen year-round) will disappear in many places. With respect to agriculture, there will mainly be positive impacts in the north, while production in Southern and Eastern Europe will decrease somewhat. Traditional tourist areas will be affected by temperature increases both summer destinations (more heat waves) and winter destinations (lack of snow). ESPERE Climate Encyclopaedia www.espere.net - People changing the Climate More - page 3
Latin America Latin America is vulnerable to climate change. It has a low adaptive capacity, especially when it comes to extreme events. Glaciers will shrink or disappear and this will have a very negative impact on the access to freshwater in areas where they provide an important source of freshwater. Both flood and drought will occur more frequently. The floods will reduce water quality in certain areas. The intensity of tropical storms is expected to increase and will result in an increased risk of loss of life, damage to property and disturbances in ecosystems. Agriculture is expected to have a lower yield and this will threaten the economy of some regions. The geographical spread of disease-carrying insects will expand towards the poles and up into the mountains. More people will be exposed to diseases like malaria, dengue fever and cholera. North America North America has a relatively high adaptive capacity and, generally, little vulnerability. The exception to this are the native people. Biodiversity loss will be increased. Sea-level rise will result in increased coastal erosion, loss of wetland areas, and more frequent storm surges, especially in Florida and along the Atlantic coast of the United States. Weather damage is expected to increase, which will result in higher insurance premiums for such conditions. Residential areas, business and industry, infrastructure, and ecosystems (especially those associated with mangrove trees) located in coastal areas will be negatively affected by sea-level rise. Agriculture will largely benefit, but the consequences will vary between regions and type of agriculture. Some unique ecosystems, including 4. Ecosystems in mangrove swamps prairies, wetlands, alpine tundra, and are vulnerable to sea-level rise. Photo: The NOAA Photo Library. cold water systems will be challenged. Diseases that can be transmitted by insects (including malaria, dengue fever and elephantiasis) will expand their scope in North America. Illness and death associated with air quality and heat spells are expected to increase. ESPERE Climate Encyclopaedia www.espere.net - People changing the Climate More - page 4
The Polar Regions The natural environment in the polar regions is highly vulnerable to climate change. Also certain native peoples are vulnerable and have little capacity and few possibilities to adapt to the changes. 5. Melting Arctic: Early spring melt - a stream is seen flowing on the ice. Photo: The NOAA Photo Library. Island states Climate change in the polar regions is amongst the most dramatic in the world and will occur the fastest. Changes have already been registered including reduced ice thickness in the Arctic, thawing of permafrost (ground that is frozen year round), coastal erosion, change in the ice cover and change in the distribution and existence of plant and animal species. The ice in the Arctic will melt faster than other ice because it lies in water. The Arctic ice can disappear entirely in a very short time, and it is not unlikely that the North Pole will be free of ice during the summer as early as the end of this century. This will have a very negative impact on biodiversity. One benefit is that the sea route from Europe to Japan will be shorter. Island states are very vulnerable and have little adaptive capacity. 6. Flooding of low-lying areas by extreme high tides. If sea level continues its rise, such events will become increasingly common. Photo: The NOAA Photo Library. Sea-level rise will cause severe damage including increased coastal erosion with loss of land and property, increased storm surges and salinisation (infiltration of salt water) of the freshwater. Adapting to such changes will require substantial resources. Weakening of coastal ecosystems will threaten the fishing industry and have a negative impact on food security and economy. Agriculture will suffer from a reduction in arable land area and the salinisation of the soil. Tourism, which is an important industry for many island states, is also expected to be sharply reduced after climate changes become evident. ESPERE Climate Encyclopaedia www.espere.net - People changing the Climate More - page 5
Part 2: IPCC The Intergovernmental Panel on Climate Change (IPCC) The Intergovernmental Panel on Climate Change (IPCC) is an international scientific organization made up of both scientists and government representatives. Its task is to assess and summarize the most recent developments in our knowledge about climate change. Firstly scientists assess our state of knowledge about climate change. Government representatives from countries all over the world then work with the scientists to simplify and condense the material so that it is useful to policymakers. This means that all countries in the world should have a shared understanding of the climate system based on our most up to date scientific understanding. The IPCC s reports form the basis for negotiations on international agreements such as the UNFCCC (the United Nations Framework Convention on Climate Change) and the Kyoto Protocol (see the next unit). Roughly every five years the IPCC releases an assessment report with contributions from several different working groups. To date, the most recent is the Third Assessment Report (TAR), which was published in 2001. TAR puts a great deal of emphasis on explaining how certain each of its conclusions is, and whether scientists agree or disagree with them. The IPCC concludes that global average surface temperatures have increased by 0.6 o C over the last hundred years and that it is likely that people have caused most of the warming over the last 50 years by emitting greenhouse gases. They conclude that we are now more certain than ever that human activity contributes significantly to global warming. Part 3: Future emissions Future emissions and climate change Our future climate will be determined partly by the amounts of greenhouse gases we emit. Levels of greenhouse gases emitted are determined by future developments in our economy, technological development and population growth. Population size, wealth, fossil fuel consumption and energy efficiency all have tremendous influences on how large our greenhouse gas emissions will be. Driving forces 1. Population size. Each person has a pattern of consumption the food we eat, the cars we drive, etc. and this results in emissions of greenhouse gases. The more people who live on the Earth, the greater the emissions. The emissions increase the most if the population growth is in the rich areas of the world. 2. Wealth. The wealthier we are, the more we consume and the bigger our emissions are. 3. Consumption of fossil fuels. Fossil fuels emit greenhouse gases when they are burnt, while renewable sources of energy, such as wind energy or solar power, do not give off such emissions. The kind of fossil fuels we burn also matters. Coal gives off more CO 2 than natural gas. ESPERE Climate Encyclopaedia www.espere.net - People changing the Climate More - page 6
4. Energy efficiency. New technologies allow us to use energy more effectively. In the future we are likely to need less energy to produce goods or services. Today a car uses between about a half to one liter of petrol to drive 10 kilometers. In the past cars needed more fuel that that. In the future we expect engines to become even more fuel efficient. Scenarios We cannot know for sure how these driving forces for climate change will look in the future but we can guess. Scientists at IPCC have constructed four very different pictures of the future, or scenarios as they are also called, to represent changes in population size, wealth, use of energy sources and energy technology up to the year 2100. All four scenarios describe a possible future world: A1B a rich world A world with very rapid economic growth, low population growth and the rapid introduction and application of new and more effective technology. A2 a heterogeneous world A world with a large gap between the rich and the poor, high rates of population growth, slow economic development, slow distribution of new technology with energy needs being met largely through fossil fuel resources. B1 a sustainable world A world of rapid changes where concern for the environment will stimulate development of new technologies to avoid using fossil fuel resources. Where new technology is spread quickly and efforts are made to close the gap between rich and poor and create a more environmentally sound economy. B2 a technologically imbalanced world A world with emphasis on local solutions for economic, social, and environmental sustainability where technology develops rapidly in some areas while other areas are forced to make do with outdated technology. 1. How CO 2 emissions might develop over the coming century, according to four different scenarios. Adapted from IPCC. ESPERE Climate Encyclopaedia www.espere.net - People changing the Climate More - page 7
For each of these very different future scenarios, scientists have estimated what the emissions of greenhouse gases would be. These emissions figures are then entered into climate models to calculate how the concentrations of greenhouse gases, temperature, sea level, and climate will be changed in each of the scenarios. These scenarios are what the IPCC have used to come up with the figure of a temperature increase between 1.4 and 5.8 C by the year 2100. To ensure that all reasonable future developments have been taken into account, they have used about 40 variations of the four scenarios where they made smaller changes in the demographics, economic growth or energy consumption estimates and used different economic models. The reason for the large difference between the highest and lowest temperature estimates is partly that there is some uncertainty about how exactly the climate system works, and partly that we cannot know precisely what the future holds in terms of social developments and emissions patterns. The IPCC says that for every emissions scenario there is a 40% chance that the temperature change will be greater than indicated, but only a 5% likelihood that it will be less. These scenarios do not take into account the possibility of countries implementing new, comprehensive measures for reducing emissions of greenhouse gases. If that happens, then both the emissions and warming can be reduced. Part 4: Vulnerability and adaptation How much a country is affected depends, of course, on how much it is exposed to climate change. For example, a country without a coastline will not experience sea level rise and it is unlikely that Northern Europe will suffer greatly from droughts. But how hard a country is hit depends not only on what particular changes it is exposed to, but how well it is able to cope with, or adapt to, these changes. In other words, the overall impact of climate change on a country depends both on its vulnerability and on its adaptive capacity. Vulnerability refers to how easily a country can be damaged by climate change. Adaptive capacity, on the other hand, refers to how able a society is to make the necessary changes to be better prepared to handle climate change. A vulnerable society with little adaptive capacity will suffer more from climate change than a society that is less vulnerable or has a greater adaptive capacity. It is often the case that the poorest countries are the worst off when it comes to both vulnerability and adaptive capacity. Example: Vulnerability to sea-level rise Today, 46 million people live in flood-endangered areas. A sea-level rise of half a meter will put 92 million people at risk, while a rise of one meter increases the number to 118 million (this is without taking future population growth into consideration). Loss of land area can be significant for coastal and island states and flat lowlands such as the Netherlands, Denmark, the Maldives, and Bangladesh. ESPERE Climate Encyclopaedia www.espere.net - People changing the Climate More - page 8
Although Denmark and the Netherlands are both rich European countries, there are differences in their vulnerability. Compared to Denmark, the Netherlands has a shorter coastline to secure plus it already has a well-developed dyke network and extensive experience in building dykes. In this sense, Denmark is more vulnerable than the Netherlands but because both are rich countries, they are both capable of building sea defences and taking action to limit the economic damage and loss of life brought about by sea-level rise. 1. Several flat coastal lands and islands may be exposed to rising sea level. Photo: NOAA Central Library In contrast, agriculture is Bangladesh s main industry and it is one of the world s poorest and most densely populated countries. It often experiences flooding and loss of human life as a result. A rise in sea-level could put large populated areas under water and put even larger areas at risk of flood. Because the country s economy and the people s access to food depends on agriculture, Bangladesh is very vulnerable to flooding and flood-related catastrophes. Moreover, a poor country like Bangladesh has little adaptive capacity because it cannot afford extensive sea defences to prepare for a rise in sea level. Bangladesh is likely, therefore, to be be seriously affected by climate change and both suffer great material and human losses. ESPERE Climate Encyclopaedia www.espere.net - People changing the Climate More - page 9