Are humans responsible for climate change?
Yes, humans are the primary cause of recent climate change (global warming since the Industrial Revolution, roughly mid-19th century onward). This is the overwhelming scientific consensus, described as “unequivocal” by major assessments.[1]
Scientific Consensus
Key Evidence from IPCC and Others
The IPCC’s Sixth Assessment Report (AR6) states: “Human activities, principally through emissions of greenhouse gases, have unequivocally caused global warming, with global surface temperature reaching 1.1°C above 1850–1900 in 2011–2020.” The best estimate attributes essentially all the observed warming to humans.[1][7]
Context and Nuance
Earth’s climate has always varied naturally (ice ages, orbital cycles, volcanic eruptions, etc.). The current warming is distinct because of its speed, the clear human GHG signal, and the fact that it occurs against a backdrop where natural forcings do not account for it. Humans are responsible for the dominant share of the warming observed since the mid-20th century (and the full industrial-era rise).[12]
Uncertainty remains in exact magnitudes of some feedbacks, regional details, and future projections under different emissions scenarios, but the core attribution—that humans are the principal cause—is established with very high confidence.[6]
In short, the evidence from observations, physics, isotopes, paleoclimate data, and models converges strongly: yes, human activities are responsible for the recent climate change.
Citations (12)
- https://www.ipcc.ch/report/ar6/syr/longer-report/
Backs: “This is the overwhelming scientific consensus, described as “unequivocal” by major assessments.”
- https://iopscience.iop.org/article/10.1088/1748-9326/ac2966
Backs: “A 2021 survey of over 88,000 climate-related papers found only a tiny fraction skeptical, concluding the consensus exceeds 99%.”
- https://news.cornell.edu/stories/2021/10/more-999-studies-agree-humans-caused-climate-change
Backs: “A 2021 survey of over 88,000 climate-related papers found only a tiny fraction skeptical, concluding the consensus exceeds 99%.”
- https://skepticalscience.com/print.php?r=18
Backs: “Earlier studies often cited ~97% consensus among climate scientists/experts; more recent ones and surveys of highly publishing experts put it even higher (often 98–100% among specialists).”
- https://science.nasa.gov/climate-change/scientific-consensus/
Backs: “Earlier studies often cited ~97% consensus among climate scientists/experts; more recent ones and surveys of highly publishing experts put it even higher (often 98–100% among specialists).”
- https://www.nationalacademies.org/news/national-academies-publish-new-report-reviewing-evidence-for-greenhouse-gas-emissions-and-u-s-climate-health-and-welfare
Backs: “National Academies of Sciences, Engineering, and Medicine, the Royal Society, AAAS, and numerous national scientific academies.”
- https://www.ipcc.ch/report/ar6/wg1/downloads/faqs/IPCC_AR6_WGI_FAQ_Chapter_03.pdf
Backs: ““Human activities, principally through emissions of greenhouse gases, have unequivocally caused global warming, with global surface temperature reaching 1.1°C above 1850–1900 in 2011–2020.” The best estimate attributes essentially all the observed warming to humans.”
- https://science.nasa.gov/climate-change/causes/
Backs: “CO₂ has risen more than 40% since pre-industrial times, with a clear isotopic “fingerprint” matching fossil carbon (not natural sources like volcanoes).”
- https://archive.vn/2023.12.09-152108/https://www.climate.gov/news-features/climate-qa/what-evidence-exists-earth-warming-and-humans-are-main-cause
Backs: “CO₂ has risen more than 40% since pre-industrial times, with a clear isotopic “fingerprint” matching fossil carbon (not natural sources like volcanoes).”
- https://royalsociety.org/news-resources/projects/climate-change-evidence-causes/
Backs: “Warming of the troposphere with cooling of the stratosphere (consistent with GHGs, not solar forcing); ocean heat content increase; ice loss; sea level rise; shifts in extremes (more hot extremes, fewer cold ones); paleoclimate records showing the current rate of change is unusually rapid.”
- https://science.nasa.gov/climate-change/evidence/
Backs: “Warming of the troposphere with cooling of the stratosphere (consistent with GHGs, not solar forcing); ocean heat content increase; ice loss; sea level rise; shifts in extremes (more hot extremes, fewer cold ones); paleoclimate records showing the current rate of change is unusually rapid.”
- https://nca5.climate.us/chapter/3/
Backs: “Humans are responsible for the dominant share of the warming observed since the mid-20th century (and the full industrial-era rise).”