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Iwant to begin by sharing with you some key conclusions on response strategies to climate change we were able to identify at the end of our last assessment three years ago. First, in most countries, governments are addressing climate change in the context of other national priorities, such as energy security and poverty alleviation. Improvements to climate policy programmes need to engage these broader national priorities. Second, in most countries it is not only national governments that are relevant to controlling emissions. Many diverse actors participate in climate policy. And this diversity will facilitate deep cuts in emissions, which require transformation in institutions, technologies, consumption patterns and human behaviour. Third, there are profound uncertainties around the socioeconomic factors related to technology development and deployment, economic growth and governance. These would multiply uncertainties found in climate science and impacts identified by the IPCC. Fourth, risk management techniques have not spread into wide use in actual mitigation strategies. We need to improve the scientific understanding of how people perceive risk and respond to different kinds of risk. Building on these conclusions and related scientific findings, the IPCC will assess the state of knowledge relevant to policymakers for the implementation of the Paris Agreement. Let me first elaborate on the special report on Global Warming of 1.5ºC that the IPCC will release next year. The UNFCCC’s Structured Expert Dialogue completed in 2015 concluded – based on IPCC AR5 science – that while the science on the 1.5ºC warming limit is less robust, parties may wish to take a precautionary route by limiting global warming as far below 2ºC as possible. The Paris Agreement subsequently invited the IPCC to provide a special report on global warming of 1.5ºC. This was a particular concern of small island states that are threatened by inundation from sea-level rise. This also poses a threat to billions of people who live on or close to coasts, raising the possibility of large-scale displacement. Understanding the risks of warming of this magnitude and the options for holding it at this level are critical, and the special report will address many of the sustainable development goals. The scientific literature on warming of 1.5ºC has since been increasing and will make possible an assessment of differences in impacts between 1.5ºC and 2.0ºC and the mitigation pathways corresponding to this temperature difference. Let me highlight a few examples. Regarding the probability of extreme temperature events, the global occurrence probability of a 1-in-a-1000 day extreme temperature event is projected to be about double as the warming increases from 1.5ºC to 2.0ºC. The probability would be five times higher than today. Mitigation pathways with a four in five chance of staying below 2ºC will be compatible with a one in two chance of 1.5º warming according to recent studies. Early DR HOESUNG LEE, CHAIR, INTERGOVERNMENTAL PANEL ON CLIMATE CHANGE (IPCC) THE SDGs AND CLIMATE CHANGE“SCIENCE CAN OFFER POLICYMAKERS VALUABLE INSIGHTS AND UNDERSTANDING ”052 CLIMATE SCIENCE