Global climate
change risks are high to very high with global mean temperature increase of 4 °C or more above preindustrial levels
in all reasons for concern (Assessment Box SPM.1), and include severe and widespread impacts on unique and threatened systems,
substantial species extinction, large risks to global and regional food security, and the combination of high temperature and
humidity compromising normal human activities, including growing food or working outdoors
in some areas for parts of the year (high confidence).