One of the most fundamental questions in climate research asks the following: What will the world look like when we reach a certain point of warming? How will it change after 2 degrees? 4 degrees? Even warmer? More than a decade ago, scientists designed a set of hypothetical scenarios to help them model the climate. Their goal was to answer these very questions. Each scenario assumes a different level of future greenhouse gas emissions and global carbon dioxide concentrations, translating to different levels of warming. The mildest scenario assumes a bold effort globally to reduce emissions over the coming decades where global temperatures would rise only about 2 degrees Celsius above their preindustrial levels through the end of the century. Several intermediate scenarios assume slightly higher levels of warming. And the […]