Is climate change real?

Is climate change real? I'll pull the evidence on what's driving the warming we see today.

Yes — climate change is real, and the scientific evidence is unequivocal that it is happening now and is primarily caused by human activity.

What the science says

> There is unequivocal evidence that Earth is warming at an unprecedented rate. Human activity is the principal cause.

NASA's Earth Science Division reaches this conclusion from decades of data from more than 20 satellites, surface stations, ocean measurements and other technologies that:

> collecting many different types of information about our planet and its climate all over the world. These data, collected over many years, reveal the signs and patterns of a changing climate.

The Intergovernmental Panel on Climate Change (IPCC), the UN body that assesses climate science with 195 member countries, used its strongest language in its Sixth Assessment Report:

> "It is unequivocal that human influence has warmed the atmosphere, ocean and land."

The same report concluded:

> warming of the climate system is unequivocal; human influence on the climate system has been the dominant cause

Overwhelming scientific consensus

> The question of whether climate change is real is no longer a matter of scientific debate. The overwhelming consensus among climate scientists, affirmed by leading scientific organizations worldwide, is that the Earth is warming, and human activity is the dominant cause.

Major summaries of the literature find:

> the vast majority of actively publishing climate scientists – 97 percent – agree that humans are causing global warming and climate change.

Other reviews have found consensus exceeding 99% to 100% among peer-reviewed papers on human-caused climate change.

Evidence for rapid climate change

The evidence comes from multiple independent lines, not a single measurement:

•Paleoclimate context: This ancient, or paleoclimate, evidence reveals that current warming is occurring roughly 10 times faster than the average rate of ice-age-recovery warming. Carbon dioxide from human activity is increasing more than 250 times faster than it did from natural sources after the last ice age

•Observable changes include:

•Global temperature rise

•Warming ocean

•Effects already seen and predicted to worsen:

> We already see effects scientists predicted, such as the loss of sea ice, melting glaciers and ice sheets, sea level rise, and more intense heat waves.

Specific measurements often cited:

•NASA's global temperature analysis identifies 2024 as the warmest individual year in its modern instrumental record, at about 1.47°C above the 1850–1900 average.

•Global mean sea level has risen about 8–9 inches (21–24 cm) since 1880. The main causes are thermal expansion of warming seawater and meltwater from glaciers and ice sheets.

•Human-made emissions in the atmosphere are trapping and slowing heat loss to space, while studies show the current warming cannot be explained by the Sun

In short, Earth's climate has always varied naturally, but the scale, speed, and cause of warming since the mid-20th century is different — it is driven principally by human greenhouse gas emissions from burning fossil fuels and land-use change, according to NASA, NOAA, the IPCC, and every major national academy of science worldwide.

Citations (1)

1nasa.govGovernment
Climate Change - NASA Science
Backs: “What the science says. There is unequivocal evidence that Earth is warming at an unprecedented rate.”