Broad range of 2050 warming from an observationally constrained large climate model ensemble

The global-mean temperature evolution over the course of the twenty-first century is uncertain. Simulations with an ensemble of thousands of climate models that reproduce observed warming over the past 50 years suggest that a mid-range greenhouse-gas emissions scenario without mitigation could lead to a warming of between 1.4 and 3 K by 2050, relative to 1961–1990.