Is climate change real? I'll pull the latest scientific evidence to answer.
Yes, climate change is real, according to overwhelming scientific evidence and consensus.
Scientific Consensus
•There is overwhelming scientific evidence that the Earth is warming and that human activities, especially the emission of greenhouse gases, are the primary cause. Multiple large-scale assessments, including those by the Intergovernmental Panel on Climate Change (IPCC), have established a strong consensus among climate scientists that global warming is real and largely human-induced.
•NASA states: There is unequivocal evidence that Earth is warming at an unprecedented rate. Human activity is the principal cause.
•According to the 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."
Quantitative studies of the consensus show:
•The vast majority of actively publishing climate scientists – 97 percent – agree that humans are causing global warming and climate change
•NASA also states “the vast majority of actively publishing climate scientists – 97 percent – agree that humans are causing global warming and climate change.”
•A 2019 review found the consensus to be at 100%, and a 2021 study concluded that over 99% of scientific papers agree on the human cause of climate change
How scientists know it is real and human-caused
Earth's climate has changed throughout history, with eight cycles of ice ages and warmer periods in the last 800,000 years, but:
•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.
•It is undeniable that human activities have produced the atmospheric gases that have trapped more of the Sun’s energy in the Earth system.
•Ancient evidence from ice cores, tree rings and other paleoclimate sources reveals that 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.
•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.
Evidence for Rapid Climate Change
NASA lists the evidence as compelling, including:
•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
•The Ocean Is Getting Warmer: Earth stores 90% of the extra energy in the ocean
•The Ice Sheets Are Shrinking: Data show Greenland lost an average of 279 billion tons of ice per year between 1993 and 2019, while Antarctica lost about 148 billion tons of ice per year
•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
•Other signs: Both the extent and thickness of Arctic sea ice has declined rapidly over the last several decades, and the acidity of surface ocean waters has increased by about 30% since the beginning of the Industrial Revolution.
In short, natural climate variability exists, but the rapid warming observed since the mid-20th century is unprecedented over millennia and is attributed by the global scientific community to human-caused greenhouse gas emissions.