Since the 1990s, scientists and policymakers have proposed limiting Earth’s average global surface temperature to 2 degrees C above pre-industrial levels, thereby averting the most serious effects of global warming, such as severe droughts and coastal flooding. But until recently, they lacked a comprehensive estimate of the likely social and economic benefits — from lives saved to economies preserved — that would result from greenhouse gas emissions reduction policies designed to achieve the 2 C goal.Now, a team of researchers from the MIT Joint Program on the Science and Policy of Global Change has published a study in Climatic Change that provides scenarios that climate scientists can use to estimate such benefits. The study projects greenhouse gas emissions levels and changes in precipitation, ocean acidity, sea level rise and other climate impacts throughout the 21st century resulting from different global greenhouse gas (GHG) mitigation scenarios. The scenarios include a business-as-usual future and one aimed at achieving significant GHG emission reductions limiting global warming since pre-industrial times to 2 C. Research groups convened by the U.S. Environmental Protection Agency have already begun using the MIT projections to evaluate the benefits of a 2 C emissions reduction scenario for agriculture, water, health, and other global concerns.