Speaking in his capacity as UN Secretary-General's Special Envoy for the Ocean and the 71st President of the UN General Assembly, as well as his role as grandfather to a five-year-old girl, Peter Thomson frames the urgent need to cap the global temperature rise at 1.5 degrees Celsius as a matter of intergenerational justice. He explains how the Paris Agreement has already helped avoid worst-case scenarios and why current 3 degrees Celsius projections remain "unacceptable."