Is climate change real?

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

Yes, climate change is real according to the overwhelming scientific evidence and consensus.

Scientific Consensus

There is a strong scientific consensus that Earth is warming and that human activities are the primary 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.

•"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."

•Multiple peer-reviewed studies show climate-warming trends are extremely likely due to human activities, with major scientific organizations endorsing this position.

•"Based on well-established evidence, about 97% of climate scientists have concluded that human-caused climate change is happening."

•Other assessments put the consensus higher in the peer-reviewed literature, including surveys finding greater than 99% agreement. The exact percentage varies by study, from about 97% to 99%+ depending on methodology.

•"Based on extensive scientific evidence, it is extremely likely that human activities, especially emissions of greenhouse gases, are the dominant cause of the observed warming since the mid-20th century."

•A joint statement of 11 international science academies stated: "Climate change is real. There will always be uncertainty in understanding a system as complex as the world's climate. However there is now strong evidence that significant global warming is occurring."

The Intergovernmental Panel on Climate Change (IPCC), the UN body that assesses climate science, has concluded:

•Comparing observations with model runs that include and exclude human influence led the IPCC to state that it is unequivocal that human influence has warmed the atmosphere, ocean and land.

•"it is unequivocal that human influence has warmed the atmosphere, oceans and land".

•"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."

Evidence That Climate Is Changing

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.

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.

Key points:

1. It is distinct from natural variability: 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.

2. Greenhouse gases are rising unprecedentedly fast: Ice cores and other paleoclimate evidence reveal 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.

3. 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.

NASA and NOAA instrumental records show the most recent decade has been the warmest on record, with continuing long-term warming trends.

4. Other physical changes consistent with warming:

•The ocean has absorbed much of this increased heat, with the top 100 meters (about 328 feet) 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 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, while Antarctica lost about 148 billion tons of ice per year.

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

•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.

•Other observed changes include decreasing spring snow cover in the Northern Hemisphere, declining Arctic sea ice extent and thickness, increasing frequency of extreme heat and intense rainfall events, and increasing ocean acidification as the ocean absorbs 20-30% of anthropogenic CO2 emissions.

In summary, multiple independent lines of evidence — temperature records, ocean heat content, ice sheet and glacier mass, sea level, and atmospheric CO2 — all point to the same conclusion: the climate is warming at an unprecedented rate, and that warming is unequivocally driven principally by human greenhouse gas emissions.

Citations (2)

1nasa.govGovernment
Scientific Consensus - NASA Science
Backs: “There is a strong scientific consensus that Earth is warming and that human activities are the primary 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…”
2nasa.govGovernment
Evidence - NASA Science
Backs: “"it is unequivocal that human influence has warmed the atmosphere, oceans and land". "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."”