Are humans responsible for climate change?

Yes — the overwhelming scientific evidence and consensus show that human activities are the main driver of climate change since the mid-20th century.

Scientific consensus
The Intergovernmental Panel on Climate Change (IPCC), based on thousands of peer-reviewed studies, states this plainly: human activities causing this warming include fossil fuel combustion, cement production, and land use changes such as deforestation, with a significant supporting role from other greenhouse gases such as methane and nitrous oxide, and this human role in climate change is considered "unequivocal" and "incontrovertible."

Multiple large-scale reviews of the scientific literature back this up:

Institutional agreement
This isn't just about individual papers — it's the position of virtually every major scientific body in the world. The evidence for global warming due to human influence has been recognized by the national science academies of all the major industrialized countries. More specifically, 200 global scientific organizations, 11 international science academies, and 18 American science associations have released statements in alignment with this consensus.

NASA summarizes the finding this way: multiple studies published in peer-reviewed scientific journals show that climate-warming trends over the past century are extremely likely due to human activities.

A note on public perception vs. scientific reality
Despite this consensus, there's often a gap in public understanding — and it matters. People who underestimate the scientific consensus on climate change are less likely to believe in (human-caused) climate change, to worry about climate change and to support public action on climate change compared to those who perceive the scientific consensus more accurately.

A caveat on the "97%" figure specifically
It's worth noting that the commonly cited "97% consensus" figure has been contested by some critics as an oversimplification — one analysis argued that the majority of papers take no position on attribution, and that when the sample isn't limited to climate specialists, support estimates vary more (in the 80–90% range for broader science samples). However, this critique concerns the precision of a specific statistic, not the underlying finding — even skeptical reviewers still find strong majority agreement among climate experts, and the more recent, larger-scale study (analyzing 88,000+ papers) found agreement approaching total consensus among papers that took a position on causation.

Bottom line: The evidence is robust and consistent across independent lines of research (temperature records, ice cores, atmospheric CO₂ measurements, climate modeling) — human emissions of greenhouse gases are the dominant driver of the rapid warming observed since the mid-20th century.