Most scientists think we have. CO2 and CH4 levels are far outside the normal levels that have existed over the past 500,000 years. We re in for a hotter climate in most areas, with benefits and drawbacks for everyone. At the very least, expect change. At worst, Kentucky may have beachfront property soon.
Earth is a closed system.
Understanding rates of change and feedback in systems is critical to solving environmental problems. Also called steady state . Positive feedback mechanisms exaggerate the process. Negative feedback mechanisms dampen the process. Temperature falls back toward normal.