snowpiercer.fandom.com/wiki/Snowpiercer_Wiki

In 2031, 17 years after an attempt to stop climate change via stratospheric aerosol injection with the fictional compound CW-7 catastrophically backfired, creating a new ice age that destroyed life on Earth, the remnants of humanity shelter in a state-of-the-art self-sustaining circumnavigational train, the Snowpiercer, run by reclusive transportation magnate Wilford. The passengers on the train are segregated, with the elite in the extravagant front cars and the poor crammed into squalid tail compartments overseen by armed guards.