More answers like this
GPT-5Sep 16, 2026openai/gpt-5-2025-08-07
Are humans responsible for climate change?
Yes
Yes. The observed warming of Earth since the mid‑20th century is overwhelmingly caused by human activities—mainly burning fossil fuels, deforestation, and some industrial/agricultural processes.
Why scientists are confident:
•Physics: Greenhouse gases (CO2, methane, nitrous oxide) trap heat; we’ve raised CO2 by about 50% above preindustrial levels.
•Fingerprints: The pattern matches greenhouse warming—troposphere warms while the stratosphere cools; nights and winters warm faster than days and summers; oceans store most of the added heat.
•Attribution studies: When models include human emissions, they reproduce the warming trend; using only natural factors (solar, volcanoes) they do not.
•Isotopes and measurements: The chemical/isotopic signature of the extra CO2 points to fossil fuels and land-use change.
Bottom line: Virtually all of the long‑term global warming since about 1950 is human‑caused. Natural variability still affects year‑to‑year swings and regional patterns, but it doesn’t explain the sustained upward trend.