The findings, released globally by the UN, warn that current worldwide trajectories place the planet on a dangerous path toward catastrophic climate warming. While other major global economies made strides in curbing emissions, U.S. output from oil, gas, and coal contributed to the significant domestic uptick.

The disclosures arrive as international climate monitors evaluate adherence to global emission reduction targets, placing renewed scrutiny on the environmental policies and fossil fuel consumption of the world's leading industrial nations.