Carbon dioxide is the most produced greenhouse gas from human activities

Nitrous oxide is the third most significant greenhouse gas made by human activities

Emissions of this molecule increased 40% from 1980 to 2020, with atmospheric concentrations reaching levels higher than at any other time in the last 800,000 years, based on ice core records. Its warming potential is 273 times that of carbon dioxide over 100 years and remains in the atmosphere for more than a century, on average.

Yearly greenhouse gas emissions have been steadily increasing since 1850

Although greenhouse gases include methane, nitrous oxide, and most fluorinated compounds, their warming potential is often measured relative to carbon dioxide. In these units, greenhouse gas emissions have gone from 4.29 billion metric tons of carbon dioxide equivalent in 1850 to 54.43 billion metric tons in 2024.

Greenhouse gas emissions from human activity accelerate recent global warming

These gases exacerbate the greenhouse effect—warming that results when the atmosphere traps heat radiating from Earth toward space. The most abundant atmospheric greenhouse gas is carbon dioxide, which is released from the burning of fossil fuels.

Excluding water vapor, greenhouse gases make up less than 1% of Earth's atmosphere

Although carbon dioxide, methane, nitrous oxide, ozone, and most fluorinated gases account for only a minority of the planet's greenhouse effect due to their lower concentrations, they are more effective at trapping thermal radiation. While water vapor condenses within two weeks, other greenhouse gases linger in the atmosphere for years on average.

Explore which sectors produce the most greenhouse gas emissions by country

As of 2023, the energy sector, including electricity and heating, accounts for the largest share of greenhouse gas emissions. The 10 largest greenhouse gas-emitting nations account for two-thirds of global emissions, with the world's top three—China, the US, and India—contributing 15 times more than the bottom 100.

Methane: the other greenhouse gas

While most of the focus with respect to greenhouse gases lands on carbon dioxide, methane is the second most potent contributor. The gas, a carbon atom with four hydrogen atoms, is 25 times more potent than CO2 in terms of trapping heat over a 100...

Greenhouse gases from farming are driven by meat

The food we eat contributes to one-third of global greenhouse gas emissions caused by human activities, according to two studies published in 2021. These emissions come from various sources along the food production chain, including transportation,...

Carbon sinks absorb more greenhouse gases than they produce

The largest on Earth are oceans, which capture 25% of all carbon emissions and 90% of excess atmospheric thermal radiation while generating half of the world's oxygen. Wildfires and deforestation have reduced forests' net sink capacity, though fungi are believed to capture and store over a third of global carbon emissions.

Human activities release 100 times the carbon dioxide of all volcanic eruptions

While gases released by volcanoes contribute to climate change, humans produce the carbon dioxide equivalent of a Mount St. Helens-sized eruption every 2.5 hours, or more than one Yellowstone eruption yearly, even though such supervolcanoes only erupt about every 100,000 to 200,000 years or more.

Watch a visualization of New York City's greenhouse gas emissions

About 1.72 tons of carbon dioxide-equivalent gases are released into the atmosphere every second in the Big Apple, enough to fill a balloon 33 feet across at standard pressure and 59 degrees Fahrenheit. After a day, the spheres would pile up into a pyramid whose base spans from the bottom of Manhattan to the south of Central Park.

Global CO2 levels as measured at Hawaii’s Mauna Loa Observatory, managed by the US government’s NOAA.

The Global Monitoring Laboratory conducts research on greenhouse gas and carbon cycle feedbacks, changes in clouds, aerosols, and surface radiation, and recovery of stratospheric ozone.

Methane leaks during natural gas processing reduce the gas's overall cleanliness

Natural gas is advertised as a cleaner fossil fuel because it emits 50% less carbon dioxide than oil and coal when burned. Supporting analysis only considers end-use combustion and excludes total emissions generated by extraction, shipping, and processing.

The US produces far more waste and recycles far less of it than other developed countries

The US represents just 4% of the world’s population, but it produces 12% of global municipal solid waste. In comparison, China and India make up more than 36% of the world’s population and generate 27% of that waste.

The Montreal Protocol helped prevent significant quantities of greenhouse gas emissions

By phasing out ozone-depleting chemicals between 1990 and 2010, the Montreal Protocol prevented emissions equal to 135 gigatons of CO₂—avoiding an estimated 0.5 to 1 degrees Celsius of additional global warming by 2100.

Coca-Cola made up roughly 19.2% of US carbonated soft drink market share as of 2023

Separately, Diet Coke made up about 7.8% of US market share that year. Pepsi was responsible for 8.3% of market share, as was Dr. Pepper.

Space tourism rockets emit up to 100 times more CO₂ per passenger than airplanes

Rocket launches release significant amounts of water vapor, nitrous oxide, and rocket propellants, which generate greenhouse gases and air pollutants. High-altitude emissions can persist for years, affecting the ozone layer.

Nuclear power supplies almost half of US carbon-free energy

As of 2023, nearly 20% of US electricity comes from nuclear power, but most reactors were built from 1971 to 1990. Expansion slowed due to safety concerns, high costs, and competition from natural gas.

As of 2025, the US and Qatar dominate global helium production

The US's 42.6% share includes helium imported from Canada and refined within the states. Geopolitical conflicts can cause supply disruptions that impact several advanced technologies, including semiconductor manufacturing, aerospace systems, and medical imaging.

Where radon comes from and why it may be the most dangerous source of radioactivity

Released from underground bedrock before passing through soil, this radioactive gas is produced from the decay of uranium, thorium, and radium and accounts for about half of all human exposure to radiation. It is the leading cause of lung cancer among nonsmokers and can build up in enclosed spaces such as buildings without proper ventilation to dilute the gas.

Artificial photosynthesis turns CO₂ into sustainable fuel

Carbon conversion focuses on a central perplexing question: if carbon dioxide is a leading driver of climate change, and fossil fuels are made of carbon-based molecules, can we devise a way to convert CO₂ into useful alternatives efficiently? This video breaks down a potential pathway using artificial photosynthesis, which uses sunlight to convert CO₂ into fuel.

The five most common chemicals found in modern food

Most modern processed foods rely on a number of preservatives to stay fresh from production to our plates. The most common include citric acid (preservative and flavor), sodium benzoate (preservative), xanthan gum (thickening and stabilizing), carrageenan (thickening), and red dyes 3 and 4 (for color).

Synthetic textiles and tires are the top sources of secondary ocean microplastics

These sources contribute more than 60% of the primary microplastics polluting the oceans, followed by city dust and road markings. City dust is made of pieces of building coatings, synthetic footwear, and other human-made objects that have broken off due to weathering and abrasion.

Cremations are America's top choice for postmortem body treatment

Though this process is the most popular one, more Americans are becoming interested in "green" burials that don't involve slowly degrading coffin materials, toxic embalming fluids or emissions from crematoria.

As of 2022, scientists estimate that 117 billion people have been born on Earth

Although no demographic data exist for more than 99% of the time humans have existed, this value can be estimated by tracking approximate population sizes over different periods and the birth rates within those periods. In 2022, about 6.8% of humans that have ever been born were alive.

The Office of Air and Radiation oversees America's clean air and climate programs

The office develops and enforces national standards for air quality, vehicle emissions, and radiation protection. In 2025, the EPA announced the closure of two key divisions under the office responsible for regulating climate and air pollution: the Office of Atmospheric Protection and the Office of Air Quality Planning and Standards.

Scientists can determine Earth's past climate conditions by analyzing air trapped in microscopic bubbles within ice cores—columns of compressed snow layers that build up over hundreds of thousands of years.

The US dollar is the most widely circulated currency in the world, and is involved in nearly 90% of global transactions

The price of gas is a composite made up of several different factors, with the federal gas tax making up less than 20% of what drivers pay at the pump.

Scientists testing how climate change affects plants found, in a years-long simulation study, that poison ivy grew 70% faster with the resulting extra carbon dioxide.

Louisiana's 'Cancer Alley' is infamous for having some of the highest industrial pollution, toxic air emissions, and cancer risks in the US.

US housing costs have risen by roughly 175% between 1991 and 2026—but a growing number of Gen Zers are becoming homeowners anyway. In 2025, 4% of homebuyers were Gen Z, up from 3% the year before.

11 people died from firework injuries in the US in 2024.

The American Society of Civil Engineers' infrastructure report card gave the US a C in 2025, its highest grade since the project launched in 1998.

As of 2025, the most cited papers in science include a review of graphene, methods to improve image recognition, streamlining electron density calculations, and optimizing protein studies.

The deadliest aspect of volcanic eruptions is often not lava, but pyroclastic flows—avalanches of ash, gas, and rock that can move more than half the speed of sound.

See how fireworks are made and learn how metals like magnesium and copper are responsible for different colors.

Artificial coral reefs have been 3D printed from nontoxic, biodegradable terracotta clay, which coral polyps have used as a foundation for rebuilding marine ecosystems.

Discover the catastrophic consequences of a failure of the US electrical grid—something that is more likely than many Americans think.

How fusion—which releases energy when two lighter atoms combine to form a heavier atom—differs from fission

Shooting stars, or meteors, are fragments of asteroids and comets that burn up as they enter Earth's atmosphere, creating streaks in the sky called meteor showers.

The Nasdaq's 'Magnificent 7' companies are responsible for roughly 40% of the Nasdaq 100 index's gains, while the remaining 93 companies account for the other 60%.

Animal phobias are likely the most common type of phobias, followed by an extreme fear of heights.

Most of the observable universe's volume consists of voids and supervoids—enormous regions of space with little to no galaxies, stars, or light.

The US first hosted the World Cup in 1994, a tournament that lives in soccer infamy for its poor planning and the murder of Colombian player Andres Escobar, who'd accidentally scored on his own net.

44% of Americans say they pray at least once a day—discover how your state's religiosity stacks up against the rest of the country.

Jimmy Carter signed a 1978 bill that legalized home brewing, a move credited with kick-starting the craft beer industry.

Apollo astronauts left items in the moon's 'toss zone,' including golf balls, family photos, and bags of human waste, to make room for lunar rocks.

In 2009, the nation was gripped by the story of a missing young boy who was believed to be floating over Colorado in a homemade balloon, until it was revealed that he was at home the whole time.

The most expensive ad of all time was for Chanel No. 5 perfume and cost roughly $33M to produce in 2004—about $57M in today's dollars.

At the beginning of the 20th century, a group of young men ate standard American food—replete with food additives like borax and formaldehyde—as part of government research to better understand food safety.