Climate Change and Its Impacts in Japan, October 2009

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Climate Change and Its Impacts in Japan, October 2009 Synthesis Report on Observations, Projections, and Impact Assessments of Climate Change Climate Change and Its Impacts in Japan October 2009 Ministry of Education, Culture, Sports, Science and Technology (MEXT) Japan Meteorological Agency (JMA) Ministry of the Environment (MOE) . Contents 1. Introduction ........................................................................................................................................1 2. Mechanisms of Climate Change and Contributions of Anthropogenic Factors — What are the Causes of Global Warming? ......................................................................................................2 2.1 Factors affecting climate change ...................................................................................................2 2.2 The main cause of global warming since the mid-20th century is anthropogenic forcing ...............3 2.3 Confidence in observation data and simulation results by models ................................................5 2.4 Changes on longer time scales and particularity of recent change................................................5 [Column 1] Definitions of Terms Related to Climate Change .....................................................8 [Column 2] Aerosols and Climate Change..................................................................................10 3. Past, Present, and Future of the Climate — What is the Current State and Future of Global Warming?.........................................................................................................................................11 3.1 Observed climate change — Is global warming really happening?...........................................11 (1) Changes in temperature .......................................................................................................12 [Column 3] Urban Heat Island Effect and Global Warming ....................................................17 (2) Changes in precipitation........................................................................................................18 [Column 4] Frequency of Short-term Heavy Precipitation and Global Warming ....................21 (3) Tropical cyclones....................................................................................................................22 (4) Changes in the sea level........................................................................................................23 (5) Ocean Acidification................................................................................................................24 3.2 Projected climate change in the future – How serious will the global warming be? .....................26 (1) Greenhouse gas emission scenario .......................................................................................26 [Column 5] Climate change projection models...........................................................................27 (2) Projection of temperature .....................................................................................................29 [Column 6] Trend of the recent global average temperature ....................................................35 (3) Projection of precipitation.....................................................................................................36 (4) Projection of Tropical Cyclones.............................................................................................40 (5) Projection of sea level............................................................................................................41 (6) Greenhouse gas stabilization scenario and global temperature increase...........................41 [Column 7] Climate change projection models and the Earth Simulator .................................44 4. Impacts of, and adaptation to, climate change..............................................................................45 4.1 Impacts of climate change on different sectors – What kind of impacts will occur in different sectors? ...........................................................45 (1) Change in annual average temperature and sector-specific impacts .................................46 [Column 8] Large and abrupt changes in earth system ............................................................48 (2) Water Environment and Water Resources...........................................................................52 (3) Water-related Disasters and Coastal Areas.........................................................................53 (4) Natural Ecosystems ..............................................................................................................54 (5) Food .................................................................................................................................56 [Column 9] Impacts of climate change on ecosystems ...............................................................57 (6) Health .................................................................................................................................59 (7) Human Well-being and Urban Life ......................................................................................60 4.2 Adaptation to future climate change – What adaption measures are required? ..........................61 (1) Needs for adaptation .............................................................................................................61 (2) Foundations for adaptation...................................................................................................62 (3) Approaches and specific measures for adaptation...............................................................62 5. Approaches to the observations and projection of climate change and impact assessment, as well as future visions – What information and knowledge is made available in the near future?.................................64 (1) Initiatives for observation.....................................................................................................64 (2) Initiatives for projection........................................................................................................65 (3) Initiative for impact assessment ..........................................................................................66 6. Conclusions......................................................................................................................................68 Acknowledgements..............................................................................................................................68 Glossary................................................................................................................................................69 References ............................................................................................................................................72 List of members of the Expert Committee on “Synthesis Report on Observations, Projections, and Impact Assessments of Climate Change”........................................................74 *Figures, graphs, and photographs in this report may not be used without permission. Please contact the Ministry of the Environment in Japan (http://www.env.go.jp/en/) before using them. Materials in this report must be accompanied by a clear indication of their sources when used in other materials. 1. Introduction long time. If its emissions exceed sequestration by land ecosystems and oceans, the GHG concentration The United Nations Framework Convention on in the atmosphere will increase. Increases in GHG Climate Change (UNFCCC), adopted in 1992, set out concentration lead to the warming of the Earth, its ultimate objective as the “stabilization of triggering a range of phenomena including sea-level greenhouse gas concentrations in the atmosphere at a rise and exerting detrimental effects on ecosystems level that would prevent dangerous anthropogenic and human society. To cope with this climate change interference with the climate system.” It state that problem, it is necessary to implement both mitigation “such a level should be achieved within a time-frame measures to control GHG emissions and adaptation sufficient to allow ecosystems to adapt naturally to measures to alleviate climate change impacts by climate change, to ensure that food production is not modifying human, social, and economic systems, threatened and to enable economic development to based on the adequate understanding of the climate proceed in a sustainable manner.” To achieve this system and the present state of climate change. In the ultimate objective, various efforts to reduce long-term, it will be necessary to stabilize GHG greenhouse gas (GHG) emissions are ongoing, based concentrations at a level not imposing dangerous on the Kyoto Protocol which was adopted in 1997 at anthropogenic interference on the climate system as the Third Conference of the Parties (COP3) of set out in the ultimate objective of the UNFCCC. Low carbon society UNFCCC. International negotiations are also under GHG concentration way aiming at reaching an agreement at COP15 to be stabilization held in December 2009 on the framework beyond 2012 following the Kyoto Protocol’s first commitment period (2008–2012). In 2007, the Intergovernmental Panel on Climate (1) Society (2) Carbon cycle Economic activities Atmospheric Change (IPCC) published the fourth assessment report GHG emissions concentrations (AR4) as an exhaustive compilation of research
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