Is climate change real?

Is climate change real? I'll pull the latest scientific evidence to give you a grounded answer.

Yes, climate change is real — this is the established position of the science.

What scientists agree on

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

Scientific evidence continues to show that human activities (primarily the human burning of fossil fuels) have warmed Earth's surface and its ocean basins, which in turn have continued to impact Earth's climate.

This is based on over a century of scientific evidence and is supported by:

•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 strong scientific consensus that climate change is real and primarily caused by human activities

•There is scientific consensus that the Earth has been consistently warming since the start of the Industrial Revolution, that the rate of recent warming is largely unprecedented

Major scientific organizations explicitly endorse this:

•Statement on Climate Change from 18 Scientific Associations: "Observations throughout the world make it clear that climate change is occurring, and rigorous scientific research demonstrates that the greenhouse gases emitted by human activities are the primary driver." (2009)

•American Association for the Advancement of Science: "Based on well-established evidence, about 97% of climate scientists have concluded that human-caused climate change is happening." (2014)

•The Intergovernmental Panel on Climate Change (IPCC) — the UN body that synthesizes climate science for policymakers — 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." and also "human influence is the principal driver of many changes observed across the atmosphere, ocean, cryosphere, and biosphere"

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

How do we know?

Scientific information taken from natural sources (such as ice cores, rocks, and tree rings) and from modern equipment (like satellites and instruments) all show the signs of a changing climate.

Earth-orbiting satellites and new technologies have helped scientists see the big picture, 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.

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

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.

Key lines of evidence listed by NASA include:

•Global Temperature Is Rising — The planet's average surface temperature has risen about 2 degrees Fahrenheit (1 degrees Celsius) since the late 19th century, a change driven largely by increased carbon dioxide emissions into the atmosphere and other human activities. Most of the warming occurred in the past 40 years.

•The Ocean Is Getting Warmer — The ocean has absorbed much of this increased heat, with the top 100 meters of ocean showing warming of 0.67 degrees Fahrenheit (0.33 degrees Celsius) since 1969. Earth stores 90% of the extra energy in the ocean.

•The Ice Sheets Are Shrinking — The Greenland and Antarctic ice sheets have decreased in mass

•Glaciers Are Retreating — Glaciers are retreating almost everywhere around the world — including in the Alps, Himalayas, Andes, Rockies, Alaska, and Africa

•Sea Level Is Rising — Global sea level rose about 8 inches (20 centimeters) in the last century. The rate in the last two decades, however, is nearly double that of the last century

•Arctic Sea Ice Is Declining — Both the extent and thickness of Arctic sea ice has declined rapidly over the last several decades

Other evidence includes decreased spring snow cover, increasing frequency of extreme events like record high temperatures and intense rainfall, and ocean acidification where the acidity of surface ocean waters has increased by about 30% since the beginning of the Industrial Revolution.

In short, climate change is not just a theory about the future — it is an observed, measured change happening now, and the scientific community overwhelmingly agrees it is primarily driven by human greenhouse gas emissions.

Citations (1)

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