Professor Valérie Masson-Delmotte:

In respect of the four pathways, the report assessed many pathways, some with no overshoot above 1.5o Celsius and others with overshoot. There are four illustrative pathways with more details given in the summary for policy makers. The only one that avoids large-scale deployment of bioenergy with capture and storage is the one with low demand - the sobriety pathway. There is a sustainable pathway, a middle-of-the-road pathway and one with a larger degree of consumerism. That is the one that relies on very large-scale bionenergy with capture and storage and implies an overshoot and return to 1.5o Celsius, with a risk of irreversible effects on ecosystems and people in the case of an overshoot.