Are we driving today's climate change? I'll pull the latest scientific evidence to answer.
Yes - according to the overwhelming scientific evidence, humans are responsible for the current climate change.
1. Scientific consensus
> There is unequivocal evidence that Earth is warming at an unprecedented rate. Human activity is the principal cause.
NASA and other agencies summarize the position as:
•Scientists attribute the global warming trend observed since the mid-20th century to the human expansion of the "greenhouse effect"
•In its Sixth Assessment Report, the Intergovernmental Panel on Climate Change, composed of scientific experts from countries all over the world, concluded that 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.
The strength of agreement is extremely high:
•Scientific consensus identifying humans as primarily responsible for climate change is not new and was already forming in the 1980s. Today, 97% to 99.9% of climate scientists agree that climate change is happening and that human activity is the primary cause.
•Multiple independent analyses of the peer-reviewed literature and surveys of climate experts put agreement that humans are causing recent warming at roughly 97% or higher, with some large-scale literature reviews reporting consensus estimates above 99%
2. What the IPCC says
The Intergovernmental Panel on Climate Change (IPCC) has increased its certainty over time:
•AR5 found that it was extremely likely that "human influence has been the dominant cause of the observed warming since the mid-20th century". According to the IPCC's calibrated language, this means that scientists were between 95% and 100% sure that humans were warming the planet. For AR6, the authors conclude that it is "unequivocal that human influence has warmed the atmosphere, ocean and land".
•More generally: The IPCC AR6 concludes that it is unequivocal that humans have caused the earth's climate to warm, with a likely human contribution of 0.8 to 1.3 degrees Celsius to global mean temperature since the late 1800s.
•It is "unequivocal" that human activity is driving climate change, and it's affecting Earth's oceans, atmosphere, ice and biosphere in ways that are "widespread and rapid," according to the report.
•The Sixth Assessment Report was described as : "It is a statement of fact, we cannot be any more certain; it is unequivocal and indisputable that humans are warming the planet"
An evolution of IPCC language shows growing certainty:
•2001: "Most of the observed warming over the last 50 years is likely to have been due to the increase in greenhouse gas concentrations."
•2013: "It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century."
•2021: "It is unequivocal that human influence has warmed the atmosphere, ocean and land."
3. How humans cause it
The mechanism is the enhanced greenhouse effect:
•The greenhouse effect is essential to life on Earth, but human-made emissions in the atmosphere are trapping and slowing heat loss to space.
•Five key greenhouse gases are carbon dioxide, nitrous oxide, methane, chlorofluorocarbons, and water vapor.
Human activities have greatly increased their concentration:
•The industrial activities that our modern civilization depends upon have raised atmospheric carbon dioxide levels by nearly 50% since 1750
•This increase is due to human activities, because scientists can see a distinctive isotopic fingerprint in the atmosphere.
Direct observations confirm the theory:
•Climate modelling predicts that human activities are causing the release of greenhouse gases and aerosols that are affecting Earth's energy budget. Now, a NASA study has confirmed these predictions with direct observations for the first time: radiative forcings are increasing due to human actions, affecting the planet's energy balance and ultimately causing climate change.
•"It's direct evidence that human activities are causing changes to Earth's energy budget."
4. Is it natural variability?
Natural climate variability is real, and climate has changed in the past due to orbital changes, solar activity and volcanism. However:
•Natural processes driving Earth's long-term climate variability do not explain the rapid climate change observed in recent decades.
•The only explanation that is consistent with all available evidence is that human impacts are playing an increasing role in climate change.
•Finally, no other known climate influences have changed enough to account for the observed warming trend.
•Taken together, these and other lines of evidence point squarely to human activities as the cause of recent global warming.
Specifically for the sun:
•While the Sun has played a role in past climate changes, the evidence shows the current warming cannot be explained by the Sun.
•Since 1750, the average amount of energy from the Sun either remained constant or decreased slightly
Other NOAA summary:
> Yes, by increasing the abundance of greenhouse gases in the atmosphere, human activities are amplifying Earth's natural greenhouse effect. Virtually all climate scientists agree that this increase in heat-trapping gases is the main reason for the 1.8°F (1.0°C) rise in global average temperature since the late nineteenth century.
In short: climate has always changed naturally, but the rapid warming since the mid-20th century - about 1.1°C since pre-industrial times - is unequivocally dominated by human emissions of greenhouse gases from burning fossil fuels, deforestation, agriculture and industry.