10 frågor och svar
När halten av växthusgaser ökar i atmosfären stannar mer värme kvar vid jordytan. Jordens naturliga växthuseffekt förstärks, temperaturen stiger och klimatet förändras med risk för allvarliga effekter runt om i världen. Den främsta orsaken till växthuseffektens förstärkning är utsläpp av växthusgasen koldioxid.
What´s happening to the climate? 10 FAQs on climate change The greenhouse effect and global warming When the level of greenhouse gases in the atmosphere increases, more heat is trapped at the earth’s surface, reinforcing the natural greenhouse effect. As a result, temperatures rise and the climate changes, with potentially devastating effects around the world. The overwhelming evidence tells us that the main reason for global warming is the increase in emissions of carbon dioxide. Put simply, the more carbon dioxide there is in the atmosphere, the warmer it becomes. 1. Is mankind really to blame for climate change? It is a sobering fact that the level of carbon dioxide in the atmosphere has increased by over 35 per cent since the middle of the nineteenth century and the earth’s average temperature has risen by 0.7 degrees since the beginning of the twentieth century. These trends have coincided with a steady increase in our use of coal, oil, natural gas, diesel and petrol. In the mid-nineteenth century we started burning coal on a large scale to heat our homes and supply industry with energy. Next came cars powered by petrol, and then oil-fired boilers to heat our homes, workplaces and public buildings. Since then the sheer quantity of cars, heating and products made using fossil fuels has increased at a staggering rate Although the climate has always alternated naturally between warm and cold periods, it is hard to deny that the current rapid increase in temperature is being exacerbated by human activity. Research points strongly to the fact that our emissions are contributing significantly to rising temperatures. Humans have the greatest impact! Photograph: Magnus Wahman/IMS For short errands, use your bicycle or walk. Not only does it help the environment and save on costs, but it also benefits your health. 2. So, how much will emissions need to decrease? To prevent serious consequences, the world’s nations need to start reducing their emissions of carbon dioxide and other greenhouse gases as soon as possible. If we are to meet the EU’s climate target of a maximum rise in temperature of two degrees, present-day emissions will have to decrease by at least 60 per cent between now and 2050. Emissions will have to start to decrease within the next few years. This represents a great challenge for the global community. The United Nations Intergovernmental Panel on Climate Change (IPCC) notes with concern that global emissions of carbon dioxide today rather than decreasing are in fact continuing to increase. Carbon dioxide emissions have risen by 80 per cent since 1970. And no reversal of the trend is yet in sight. The situation is serious, but scientists also point out that there are ways in which emissions can be sufficiently reduced with the help of present-day technology and renewable fuels. But if this is to happen, both individuals and businesses will need to show both willingness and resolve. Emissions need to decrease sharply! Photograph: Janis Christie/Matton Avoid using drying cupboards and tumble dryers. Clothes can be hung up to dry in the laundry, using air dehumidifiers if necessary, or if you have a suitable space you can dry your washing outdoors. 3. But does it really matter if it becomes a few degrees warmer? If the average temperature of the earth rises by 2-4 degrees by the end of this century, which the IPCC, the UN’s panel on climate change, considers likely, sea levels may rise by half a metre. If global warming leads to land ice in Greenland and Antarctica starting to melt, sea levels may rise much further still. Millions of people are at risk from poorer health as insects and diseases spread. Access to drinking water may become more difficult, and many plants and animals will be threatened with extinction as their habitats change so rapidly that they do not have time to adapt. It is also feared that a warmer climate may lead to more extreme weather events such as long periods of drought and heavy rainfall. The effects are expected to be particularly serious in parts of the world that are already at risk. Further drought in areas already short of water may, for example, force millions of people to flee from water shortages and famine. Risk of extreme weather and new diseases! 4. How will we be affected here in Sweden? It is estimated that mean temperatures in Sweden will rise more than the average for the earth. This will mean milder winters and more frequent, heavier rainstorms. A warmer climate may also have some positive effects. Conditions for crop cultivation may improve, which is good for agriculture and forestry. Milder winters may, however, spread harmful insects and diseases that pose a threat both to crop yields and to the forests. Increased precipitation and more intensive downpours will increase the risk of flooding along rivers, streams and lakes. Higher sea levels will contribute to increased coastal erosion in Skåne, and combined with storms may increase the risk of flooding in coastal towns. Plants and animals will be affected. The flora and fauna of the Swedish mountains and the Baltic Sea are regarded as particularly vulnerable. A generally wetter and milder climate will also favour ticks, notorious for spreading certain diseases. Warming may also adversely affect the availability and quality of drinking water. Warmer and wetter in Sweden! 5. Can we put a stop to climate change? Yes we can, if we radically reduce our use of coal, oil, natural gas, petrol and diesel. But we have to anticipate certain effects. The climate will react to our emissions for a long time to come, even if global emissions decrease immediately. Swedish climate strategy aims to halve Swedish greenhouse gas emissions by 2050. Great changes are required if this is to be achieved. Like other countries, Sweden will have to make a greater commitment to investing in new, energy-efficient technology and renewable energy. We will also have to become more economical in our use of energy. This is true for buildings, transport and industry. ‘Clean’ cars, energy-smart houses and energy-efficient businesses are the way forward. Every country, every sector of society, every business and every member of society will therefore have to contribute to reducing emissions. Photograph: Magnus Fond/Johnér bildbyrå We all need to reduce our emissions! Buy food that’s in season and if possible produced locally. 6. How can we adapt? Exactly how climate change will affect us will differ from region to region and country to country. Even though we are not completely sure what the effects will be, adaptation to a warmer climate needs to start now. In Sweden we need to seriously consider the risk of flooding and higher sea levels when we build new homes and infrastructure. Likewise, more cooling systems and ventilation in buildings will be needed so that the elderly and children are not affected by prolonged heat waves, for example. In agriculture and forestry, crops appropriate to the new weather conditions will have to be chosen. A warmer climate may also necessitate costly investments. In southern Sweden there is discussion, for instance, about how to divert the water from increased precipitation around Lake Vänern to the sea without increasing the risk of landslides in the valley of the Göta Älv river. A new canal or tunnel to the coast is being considered. It’s important that we start now! 7. Whose job is it? Political decisions at all levels, locally, nationally and internationally, are important in reducing emissions. International cooperation under the UN Framework Convention on Climate Change is particularly significant. Trading in emission allowances is taking place in the EU, for instance, to reduce emissions from industry and energy companies. The Swedish Parliament has decided on a number of measures, such as increased energy taxes, lower tax on renewable fuels, fuel-efficient cars and other types of grants for energy efficiency improvements. Decisions that affect emissions and consequently the climate are taken every day in local authorities and businesses. The increase in mean global temperature can be limited if we all make use of the opportunities that actually exist. Reducing emissions demands both political decisions and personal commitment. We all need to do our bit! 8. Does it really matter what I do myself? Believe it or not, here in Sweden, households account for almost half of emissions that affect the climate. What you buy and where you buy it, what you eat, how you travel, what temperature you keep your home at and how much you use lights, computers and domestic appliances: all these choices matter a lot. If you save electricity, no energy needs to be imported from coal and oil-fired power stations. It will be cheaper too. Replacing an oil-fired boiler with one that burns pellets will pay for itself in a few years. Changing to a fuel-efficient or clean car will reduce emissions. If you also leave the car at home and walk, cycle or take public transport instead, carbon dioxide emissions can be reduced still further. What’s more you will save money and you’ll be healthier. Photograph: Per Magnus Persson/Johnér bildbyrå Everything you do matters! Replace ordinary light bulbs with low-energy lamps. It will pay for itself. They are five times more efficient and last ten times longer. 9. Developing countries are worst affected – what can we do? It’s a cruel irony that the industrialised world causes most human climate impact, however it’s developing countries that suffer most. So it’s up to us to make the biggest effort. We in the rich world need to face up to the harm we are inflicting on people in developing countries and indeed island nations prone to flooding. Many developing countries need our help now in adapting to climate change. At the same time we can also help them to introduce energy-efficient technology so that emissions do not increase as these countries’ economies grow. And of course we must continue to work to reduce emissions in Sweden and in other industrialised countries. Only then will we really be able to limit the effects of climate change. Photograph: Johan Ödman/Johnér bildbyrå We need to take responsibility! We must all do our bit to create a good environment for both ourselves and future generations to live in by reducing our greenhouse gas emissions now. 10. When and how will we know that we have succeeded? Global greenhouse gas emissions are constantly on the rise. The UN’s Intergovernmental Panel on Climate Change (IPCC) is convinced that emissions will need to start to decrease soon if there is not to be a risk of serious changes to the earth’s climate. The next 20 years are considered crucial in deciding how great the change in the climate will be. Sweden and the EU have set a target of mean global temperature not rising by more than two degrees. On the way to meeting Swedish climate targets, there are a number of “checkpoints” at which development is assessed and decisions can be taken on more and stronger measures. Greenhouse gas emissions in Sweden have fallen since 1990. But many new measures are still required if emissions are to decrease to a sufficient extent. The IPCC regularly assesses our impact on the climate and offers advice to governments around the world. The most recent assessment was made in 2007. The conclusions drawn in these reports indicate that the world has started moving in the right direction. The next 20 years are important! Further reading You can find plenty of reading material on climate change. Visit the following websites: Swedish Environmental Protection Agency: www.naturvardsverket.se/klimat Swedish National Road Administration: www.vv.se Swedish Energy Agency: www.energimyndigheten.se Swedish Consumer Agency: www.konsumentverket.se Swedish Meteorological and Hydrological Institute (SMHI): www.smhi.se Further brochures can be ordered free of charge at www.naturvardsverket.se/klimat >Bokhandel och bibliotek or at firstname.lastname@example.org ISBN 978-91-620-8303-8 106 48 Stockholm Tel +46-8-698 10 00 Engström med flera www.mfl.se Photograph on cover: Lena Paterson/Tiofoto.