Sweden facing climate change – threats and opportunities Final report from the Swedish Commission on Climate and Vulnerability Stockholm 2007 Swedish Government Official Reports SOU 2007:60 This report is on sale in Stockholm at Fritzes Bookshop. Address: Fritzes, Customer Service, SE-106 47 STOCKHOLM Sweden Fax: 08 690 91 91 (national) +46 8 690 91 91 (international) Tel: 08 690 91 90 (national) +46 8 690 91 91 E-mail: [email protected] Internet: www.fritzes.se Printed by Edita Sverige AB Stockholm 2007 ISBN 978-91-38-22850-0 ISSN 0375-250X Preface The Commission on Climate and Vulnerability was appointed by the Swedish Government in June 2005 to assess regional and local impacts of global climate change on the Swedish society including costs. Bengt Holgersson Governor of the County Administrative Board in the region of Skåne was appointed head of the Com- mission. This report will be subject to a public review and will serve as one of the inputs to a forthcoming climate bill in 2008. The author have the sole responsibility for the content of the report and as such it can not be taken as the view of the Swedish Government. This report was originally produced in Swedish. It has been translated into English and the English version corresponds with the Swedish one. However, one chapter with specific proposals for changes in Swedish legislation was not translated, nor were the appendices translated. Hence, these are only available in the Swedish original version. Contents 1 Summary................................................................... 11 2 The assignment and background.................................. 35 2.1 The assignment, scope and approach...................................... 35 2.1.1 Background ................................................................... 35 2.1.2 The commission’s terms of reference ......................... 36 2.1.3 Scope.............................................................................. 37 2.1.4 Approach and methodology ........................................ 38 2.2 International work ................................................................... 43 2.2.1 Global climate collaboration........................................ 43 2.2.2 The EU’s work.............................................................. 46 2.2.3 Adaptation work in other countries............................ 53 2.3 Earlier examinations of the issues........................................... 67 Bibliography ...................................................................................... 73 3 The climate – past, present and future ......................... 75 3.1 The regional development of the climate to the present day............................................................................................. 75 3.1.1 Typical features of the Swedish climate ...................... 75 3.1.2 The climate since the Ice Age ...................................... 76 3.1.3 The climate during the 20th century ........................... 79 3.1.4 The climate over the past few decades ........................ 81 3.1.5 The climate for the different seasons over the reference period 1961-1990.......................................... 83 3.2 Extreme weather events in recent years ................................. 92 3.2.1 Storms ........................................................................... 92 3.2.2 Floods and high flows .................................................. 97 5 Contents SOU 2007:60 3.2.3 Landslides, erosion......................................................100 3.2.4 Extreme temperatures.................................................102 3.2.5 Ice formation...............................................................102 3.2.6 Heavy snowstorms......................................................103 3.3 Global changes in climate ......................................................103 3.3.1 Increased certainty about the causes of global warming observed to date...........................................103 3.3.2 Increasing concentrations of greenhouse gases lead to continued warming .........................................106 3.3.3 Feedback mechanisms, climate in the longer term and the risk of sudden climate change.......................108 3.4 Choice of scenarios and models ............................................117 3.4.1 Characteristics of emissions scenarios.......................117 3.4.2 Our choice of scenarios and models..........................119 3.5 How will the climate change in Sweden and our immediate vicinity? ................................................................124 3.5.1 Considerably warmer in the future............................127 3.5.2 Wetter winters, drier summers in the south, higher flows .................................................................135 3.5.3 Windier or not?...........................................................145 3.5.4 Changes in the Baltic Sea............................................147 3.5.5 Specific climate indices for analysing vulnerability.................................................................152 Bibliography.....................................................................................155 4 The Consequences of Climate Change and Extreme Weather Events ........................................................161 4.1 Communications....................................................................161 4.1.1 Roads ...........................................................................161 4.1.2 Railways .......................................................................174 4.1.3 Shipping .......................................................................184 4.1.4 Aviation .......................................................................189 4.1.5 Telecommunication ....................................................195 4.1.6 Radio and TV distribution..........................................200 4.2 Technical support systems.....................................................204 4.2.1 Electricity supply systems and power potential........204 4.2.2 Dams............................................................................226 6 SOU 2007:60 Contents 4.2.3 Heating and cooling needs......................................... 239 4.2.4 District heating ........................................................... 245 4.2.5 Drinking water supply................................................ 249 4.3 Developments and buildings................................................. 261 4.3.1 Flooding of waterfront developments ...................... 261 4.3.2 Landslide and erosion................................................. 275 4.3.3 Coastal erosion ........................................................... 288 4.3.4 Storm water systems and waste water overflow ....... 298 4.3.5 Building structures ..................................................... 309 4.3.6 Pollutant dispersion in flooding and landslide ......... 315 4.4 Rural businesses and tourism................................................ 325 4.4.1 Forestry....................................................................... 325 4.4.2 Agriculture .................................................................. 343 4.4.3 The fishing industry ................................................... 361 4.4.4 Reindeer herding......................................................... 375 4.4.5 Tourism and outdoor activities.................................. 384 4.5 The natural environment and environmental goals ............. 396 4.5.1 Terrestrial ecosystems, biodiversity and other environmental goals.................................................... 396 4.5.2 The freshwater environment...................................... 409 4.5.3 The Baltic Sea and the marine environment.............. 416 4.6 Human health......................................................................... 424 4.6.1 Extreme temperatures ................................................ 426 4.6.2 Altered air quality....................................................... 432 4.6.3 Health effects of floods, storms and landslides........ 439 4.6.4 Spread of infection...................................................... 440 4.7 Changes in the world around us and their impact on Sweden.................................................................................... 448 4.8 Combined effects on society................................................. 459 4.8.1 Socioeconomic development in Sweden ................... 459 4.8.2 Combined cost assessments....................................... 466 4.8.3 Damage cost scenarios ............................................... 487 4.8.4 Other consequences ................................................... 502 4.8.5 Global and regional studies of climate consequences............................................................... 510 References........................................................................................ 516 7 Contents SOU 2007:60 5 Support and instruments for reduced vulnerability .......529 5.1 Mapping of floods, landslides and erosion ...........................529 5.1.1 Existing flood and stability mapping and inventory of shore erosion .........................................529 5.1.2 Use of mapping in the municipal planning process .........................................................................535 5.1.3 Mapping in a changed climate, considerations and proposals......................................................................538 5.2 Databases and knowledge