BackgroundTurn Down the Heat: Climate Extremes, Regional Impacts, and the Case for Resilience builds on a World Bank report released late last year, which warned the world would warm by 4 degrees Celsius 4°C or 7.2 degrees Fahrenheit above pre-industrial levels by the end of this century if we did not take concerted action now, with dire consequences. This new report looks at the likely impacts of present day, 2°C and 4°C warming on agricultural production, water resources, coastal ecosystems and cities across Sub-Saharan Africa, South Asia and South East Asia:Under current levels of warming, significant climate and development impacts are already being felt. With temperatures at 0.8°C 1.4 ºF above pre-industrial levels, the last decade has seen extreme weather events resulting in widespread human suffering and increasing economic damage across all regions. Sea levels have been rising more rapidly than previously projected. A rise of as much as 50 cm by the 2050s may already be unavoidable as a result of past emissions. Impacts could be felt much earlier. A rise of 15 cm, coupled with more intense cyclones, threatens to inundate much of Bangkok by the 2030s.A warming of 2°C 3.6 °F above pre-industrial levels, may be reached in 20 to 30 years. In Sub-Saharan Africa, food shortages will become more common. In South Asia, shifting rain patterns will leave some areas under water and others without enough water for power generation, irrigation or drinking. In South East Asia, the degradation and loss of reefs would diminish tourism, reduce fish stocks, and leave coastal communities and cities more vulnerable to increasingly violent storms and landslides.As warming goes from 2ºC 3.6ºF to 4°C 7.2 ºF, multiple threats of more extreme heat waves, rising sea–levels, more severe storms, droughts and floods will have severe implications for the poorest and most vulnerable. In Sub-Saharan Africa, by the 2030s droughts and heat will leave 40% of the land now growing maize unable to support the crop. Rising temperatures could cause major loss of savanna grasslands threatening pastoral livelihoods. In South Asia, a potential change in the regularity and impact of the monsoon could precipitate a major crisis in the region. Events like the devastating Pakistan floods of 2010, which affected more than 20 million people, could become common place. Across South East Asia, rural livelihoods are faced with mounting pressures as sea levels rise, tropical cyclones increase in intensity and important marine ecosystem services are lost as warming approaches 4°C. Across all regions, the growing movement of impacted communities into cities could lead to higher numbers of people in slums and other informal settlements being exposed to heat waves, flooding, mudslides and diseases.