Is climate change real?

Is climate change real? I'll gather the latest scientific evidence to answer you.

Yes, climate change is real — this is supported by unequivocal scientific evidence and overwhelming scientific consensus.

What scientists say

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

NASA also states:

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

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

The United Nations Intergovernmental Panel on Climate Change (IPCC), established in 1988 to advance scientific knowledge about climate change caused by human activities, stated in its 2023 report that "Human activities, principally through emissions of greenhouse gases, have unequivocally caused global warming.

According to NASA / IPCC:

> 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.

Why scientists are confident

Earth's climate has naturally changed throughout history. For example:

> Just in the last 800,000 years, there have been eight cycles of ice ages and warmer periods

However:

> 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.

Evidence from natural sources such as ice cores, rocks, and tree rings and from modern equipment like satellites all show signs of a changing climate.

Paleoclimate evidence shows:

> current warming is occurring roughly 10 times faster than the average rate of warming after an ice age. Carbon dioxide from human activities is increasing about 250 times faster than it did from natural sources after the last Ice Age.

The compelling evidence for rapid climate change includes:

•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, with the seven most recent years being the warmest.

•The Ocean Is Getting Warmer: The ocean has absorbed much of this increased heat, with the top 100 meters of ocean showing warming. 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. Data from NASA's Gravity Recovery and Climate Experiment show Greenland lost an average of 279 billion tons of ice per year between 1993 and 2019

•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 and accelerating slightly every year.

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

•Other signs: Snow cover decreasing, extreme events increasing in frequency, and ocean acidification increasing by about 30% since the beginning of the Industrial Revolution.

In short, while natural climate variability exists, direct measurements of rising surface and ocean temperatures, rising sea level, shrinking ice, and rising greenhouse gases collected over many years reveal the signs and patterns of a changing climate, all pointing to current human-caused warming that is unprecedented in at least the past 10,000 years.

Citations (1)

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