More answers like this
GPT-5Oct 22, 2026openai/gpt-5-2025-08-07
Are humans responsible for climate change?
Yes. The warming observed over the past century is overwhelmingly caused by human activities, especially burning fossil fuels and deforestation.
Why we know:
•Greenhouse gases have risen by about 50% since the 1800s; carbon isotopes and the measured decline in atmospheric oxygen point specifically to fossil-fuel combustion.
•Physics and measurements align: increased CO2 traps heat; satellites see less heat escaping to space at CO2/CH4 wavelengths and more downward infrared at the surface.
•Characteristic “fingerprints”: troposphere warming while the stratosphere cools, faster warming at night and in winter, amplified warming in the Arctic, rising ocean heat content and sea level.
•Models only reproduce the observed long‑term warming when human emissions are included; natural factors alone (solar variability, volcanoes, internal cycles) cannot explain the trend.
Bottom line: Humans are responsible for essentially all of the net global warming since the mid‑20th century. If you’d like, I can share accessible sources (e.g., IPCC assessments and national science academies) or dive deeper into any point.