Are humans responsible for climate change?

I'll gather the current science on humanity's role in climate change to answer your question.

Yes — according to the overwhelming scientific evidence, humans are the dominant cause of the current climate change.

Scientific consensus

•Scientific evidence continues to show that human activities (primarily the human burning of fossil fuels) have warmed Earth's surface and its ocean basins.

•Multiple studies published in peer-reviewed scientific journals show that climate-warming trends over the past century are extremely likely due to human activities.

•Multiple methods — surveys of experts and massive literature reviews — converge on an overwhelming consensus that humans are the main cause of contemporary climate change: classic estimates cluster around 97%.

•Nearly all actively publishing climate scientists say humans are causing climate change.

•While Earth's climate has changed throughout history, the current warming is happening at a rate not seen in the past 10,000 years.

What major scientific bodies say

•The Intergovernmental Panel on Climate Change (IPCC) — the UN body that synthesizes peer-reviewed climate science — states:

> "It is unequivocal that the increase of CO2, methane, and nitrous oxide in the atmosphere over the industrial era is the result of human activities and that human influence is the principal driver of many changes observed across the atmosphere, ocean, cryosphere, and biosphere."

•Its Sixth Assessment Report (AR6, 2021-2023) concluded that human influence has unequivocally warmed the atmosphere, ocean and land. The authors conclude that it is "unequivocal" that humans have warmed the planet, causing "widespread and rapid" changes to Earth's oceans, ice and land surface.

•The IPCC also states: "Since systematic scientific assessments began in the 1970s, the influence of human activity on the warming of the climate system has evolved from theory to established fact."

•Human activities, principally through emissions of greenhouse gases, have unequivocally caused global warming.

•The American Geophysical Union: "Based on extensive scientific evidence, it is extremely likely that human activities, especially emissions of greenhouse gases, are the dominant cause of the observed warming since the mid-20th century. There is no alterative explanation supported by convincing evidence."

•NASA summarizes: There is unequivocal evidence that Earth is warming at an unprecedented rate. Human activity is the principal cause.

How humans are causing it

•Most of historical climate changes are attributed to very small variations in Earth's orbit that change the amount of solar energy our planet receives — but the current warming trend is different because it is clearly the result of human activities since the mid-1800s, and is proceeding at a rate not seen over many recent millennia.

•It is undeniable that human activities have produced the atmospheric gases that have trapped more of the Sun's energy in the Earth system.

•Carbon dioxide (CO2) is the biggest driver of recent climate change. Burning fossil fuels (coal, oil, natural gas) has pushed atmospheric CO2 from about 280 ppm before the Industrial Revolution to over 420 ppm today.

Natural factors — such as solar variations, volcanic activity, and orbital cycles — still affect climate, but measurements, the physical understanding of the greenhouse effect, and climate models show they are too small or too slow to explain the rapid warming observed since the mid-20th century. The combined positive radiative forcing from anthropogenic greenhouse gases is identified as the dominant cause.

In short, while climate has always varied naturally, the rapid warming since ~1950 is unequivocally dominated by human emissions of greenhouse gases from burning fossil fuels, deforestation, livestock production and industrial processes.

Citations (2)

1nasa.govGovernment
Scientific Consensus - NASA Science
Backs: “Yes — according to the overwhelming scientific evidence, humans are the dominant cause of the current climate change. Scientific consensus. Scientific evidence continues to show that human activities (primarily the human burning of fossil fuels) have warmed Earth's surface and its ocean basins.”
2carbonbrief.orgNews and mediaquality 0.85
In-depth Q&A: The IPCC’s sixth assessment report on climate science
Backs: “Its Sixth Assessment Report (AR6, 2021-2023) concluded that human influence has unequivocally warmed the atmosphere, ocean and land. The authors conclude that it is "unequivocal" that humans have warmed the planet, causing "widespread and rapid" changes to Earth's oceans, ice and land surface.”