Analysis
The official transcript of the 2018 UN Climate Action Summit records Espinosa Garcés saying that climate change is the greatest existential threat to humanity, that there is no "Planet B," and that time to act is running out. These claims align with the Intergovernmental Panel on Climate Change (IPCC) reports, which warn of severe, irreversible impacts if mitigation is delayed. While the phrasing is rhetorical, it is not factually inaccurate. Therefore, the statement is verified as true.
Background
María Fernanda Espinosa Garcés, former President of the UN General Assembly, addressed world leaders in September 2018, urging urgent climate action. The IPCC's Special Report on Global Warming of 1.5°C (2018) highlighted that limiting warming requires immediate, unprecedented reductions in greenhouse‑gas emissions. The "no Planet B" slogan has been widely used in climate advocacy to emphasize the lack of an alternative Earth.
Verdict summary
The quoted remarks accurately reflect María Fernanda Espinosa Garcés' statements at the 2018 UN Climate Action Summit and are consistent with the scientific consensus on climate change.