ENVIRONMENT: The Anthropocene's Carbon Budget Since industrialization, atmospheric CO2 has risen from 280ppm to 420ppm—a 50% increase in 150 years, faster than any natural climate shift in the past 800,000 years. Current emissions trajectories consume our 1.5°C warming budget (remaining ~400 gigatons CO2) in roughly 9-10 years at present rates. This matters because each tenth of a degree compounds climate impacts: 1.5°C triggers Amazon dieback risks and coral collapse; 2°C makes entire agricultural regions economically unviable and displaces hundreds of millions. The difference between staying under these thresholds and exceeding them determines whether climate change becomes a manageable crisis or an existential restructuring of civilization.