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With anthropogenic global warming, heat-related extreme events are projected to increase in severity and frequency. Already vulnerable regions like Africa will be hard-hit. Therefore, such regions could benefit from low global warming levels. Using the Community Earth System Model low warming simulations, we investigate changes in temperature extremes across Africa as a function of global mean temperature in the context of the implications of the Paris Agreement's targets. A significant warming across Africa is projected at the 1.5 degrees C warming world and is amplified at the 2 degrees C world, exceeding the mean global warming rate. Specifically, North Africa and East Africa regions are projected to have the highest and lowest temperature changes of 0.63 degrees C (0.60-0.67 degrees C) and 0.50 degrees C (0.47-0.54 degrees C), respectively, between the 1.5 and 2 degrees C warmer worlds. Consequently, hot events are also estimated to increase with global warming. We showed that limiting warming to 1.5 degrees C instead of 2 degrees C may lead to 29% (27-31%) to 35% (33-37%) reduction in severity of hot events and to 31% (30-33%) to 42% (39-48%) reduction in the frequency of the threshold-based high-temperature events across Africa. The highest reductions are projected over North Africa. Furthermore, restricting warming to 0.5 degrees C lower than 2 degrees C might also result in 28% (34-40%) to 37% (25-34%) reduction in severity of once-in-10/20-year heat events across Africa with North Africa having the highest benefits than tropical regions. Thus, restricting warming to low levels may indeed translate to substantial benefits of reduced intensity and frequency of extreme heat events across Africa.

Plain Language Summary As global warming continue to increase extreme daily temperatures, efforts to limit this warming to low levels could be of much benefit to Africa, an already vulnerable populous region. Therefore, the agreed 1.5 and 2 degrees C global warming targets under the Paris Agreement might have substantial paybacks. Here, we used a suite of unique climate simulations to investigate differences in high-temperature extremes under the 1.5 and 2 degrees C warming worlds across Africa. We found that limiting warming to 0.5 degrees C lower than 2 degrees C may lead to benefits of between 29% and 42% reductions in intensity and frequency of heat events across Africa, with the largest benefit estimated over North Africa. Currently, relatively rare once-in-20-year heat events across Africa may become approximately twice as common under 2 degrees C world as compared to under 1.5 degrees C world. Therefore, limiting global warming to 1.5 degrees C instead of the previously suggested 2 degrees C could translate into substantial benefits across Africa.