Are humans responsible for climate change?

Yes, humans are the primary cause of the current rapid climate change (global warming). This is the overwhelming scientific consensus, described as "unequivocal" by the Intergovernmental Panel on Climate Change (IPCC) and supported by multiple independent lines of evidence from observations, physics, chemistry, paleoclimate records, and climate models.[1]

Scientific Consensus

The IPCC’s Sixth Assessment Report (AR6, 2021–2023) states: “It is unequivocal that human influence has warmed the atmosphere, ocean and land.” Global surface temperature has risen about 1.1°C (roughly 2°F) above 1850–1900 levels (as of 2011–2020), with the best estimate that all of the observed warming from 1850–1900 to 2010–2019 is attributable to humans. Natural factors (solar variability, volcanoes, internal variability) contributed negligibly or slightly cooled in that period.[1]

Key Evidence

Multiple independent lines converge on the same conclusion:

Natural factors (solar cycles, orbital changes, volcanoes, internal variability like El Niño) influence climate on various timescales but cannot explain the observed post-industrial warming magnitude, pattern, or rate. Aerosols from human activity have provided some offsetting cooling, meaning the pure GHG warming effect is even larger.[1]

Notes on Nuance

Climate has always varied naturally, and humans are not the sole influence on every weather event. However, the long-term global warming trend since the Industrial Revolution—and its acceleration—is predominantly anthropogenic. Uncertainty remains in exact regional impacts, climate sensitivity details, and future projections under different emissions scenarios, but not in the primary cause of the observed change.

This conclusion rests on decades of data from satellites, weather stations, ocean buoys, ice cores, and rigorous peer-reviewed research, continuously reaffirmed and strengthened in successive assessments.