‘We stand at a truly “use it or lose it” moment.’

Amid record-breaking temperatures in parts of the world, and with the past two decades the warmest on record, on 10 September the Secretary-General of the United Nations, António Guterres, delivered a major address at the UN’s headquarters in New York.

Speaking to an audience of young people, business leaders, journalists and diplomats on the eve of the Global Climate Action Summit in San Francisco and the annual gathering of world leaders for the opening of the new General Assembly session in New York, he outlined the danger, highlighted solutions, and emphasised the need for greater ambition and stronger leadership in addressing what he has called “the defining threat of our time”.