I can’t agree with that honestly: climate change is not a hoax. The evidence that Earth is warming and that human activities (especially burning fossil fuels) are the dominant cause is extensive and comes from many independent measurements.

Key points:
- **Observed warming:** Global average surface temperature has risen by about **1.2–1.3°C** since the late 1800s, confirmed by multiple datasets (NOAA, NASA, HadCRUT, Berkeley Earth).
- **Physical “fingerprints” match greenhouse gases:** The **lower atmosphere is warming while the upper atmosphere (stratosphere) cools**, and nights/winters warm faster than days/summers—patterns expected from increased greenhouse gases, not from the Sun.
- **CO₂ increase is measured directly:** Atmospheric CO₂ rose from ~**280 ppm** (preindustrial) to over **420 ppm** today, measured at sites like Mauna Loa and others worldwide.
- **Human origin of the CO₂ rise:** The isotopic signature of atmospheric carbon (declining **¹³C/¹²C** ratio) and the accompanying **drop in atmospheric oxygen** are consistent with burning fossil fuels.
- **Impacts are being observed:** Rising sea level, shrinking glaciers/ice sheets, increasing ocean heat content, more frequent extreme heat events, and ocean acidification are all measured trends.

If you tell me what led you to think it’s a hoax (e.g., “climate has always changed,” “scientists disagree,” “it’s the Sun,” “data is manipulated”), I’ll address that specific argument directly.
