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

A look at Mauna Loa, which produces the gold standard of global CO2 measurements.

Mauna Loa Observatory is a station that measures the elements in the atmosphere that contribute to climate change. It is located on the side of the Mauna Loa volcano in Hawaii. 

Climate data is monitored globally using tools from satellites to backyard gauges

Scientists use satellites, balloons, ocean buoys, and land-based instruments to track climate variables like temperature, precipitation, and wind. These tools gather data from deep ocean waters to the upper atmosphere.

Greenhouse gas concentrations can be measured using spectroscopy

Each type of greenhouse gas absorbs a distinct set of wavelengths of light, which serve as a unique spectral signature. By shining light through an atmospheric sample and measuring the light on the other side, the amount of each gas can be calculated from the amount of missing light.

Carbon dioxide is the most produced greenhouse gas from human activities

In 2022, about 79.7% of US greenhouse gas emissions were carbon dioxide, produced through chemical reactions in processes such as cement production and the burning of fossil fuels, solid waste, trees, and other biological materials. Methane (11.1%), nitrous oxide (6.1%), fluorinated gases (3.1%), and trace amounts of solid and liquid aerosol were also created.

The impact of greenhouse gases is assessed as a measure of Global Warming Potential

Since 1990, the Intergovernmental Panel on Climate Change has used GWP to measure how much energy 1 metric ton of a gas emits over a given period—usually 100 years—relative to 1 metric ton of carbon dioxide. By definition, carbon dioxide has a GWP of 1.

The ocean's ability to store carbon long-term is being hindered by marine heatwaves

More than 4,000 robotic floats with biogeochemical data sensors, including oxygen, pH, nitrate, suspended particles, chlorophyll, temperature, and conductivity, have been deployed as part of the Global Ocean Biogeochemical Array. They have identified changes to ecosystem structure affecting the ocean's ability to transport carbon from surface waters into the deep.

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.

Watch a time-lapse from space of photosynthesis across Earth

Using NASA satellite imagery, carbon absorption can be tracked and serves as a proxy for photosynthetic activity on land and in the oceans. Over the course of a year, seasonal changes can be observed as plants become dormant in the fall and active again in the spring.

Carbon dioxide acts as a 'control knob' for Earth's climate

Although Earth's ice ages were primarily triggered by slow changes in the planet's orbit—known as Milankovitch cycles—these changes do not explain the extreme temperature swings during glacial periods. Carbon dioxide acts as a feedback mechanism, intensifying both cooling during ice ages and warming during their ends by reinforcing the initial changes sparked by orbital shifts.

Why the ratios of helium isotopes are analyzed to investigate ocean circulation

Volcanic activity on the seafloor produces high ratios of helium-3 to helium-4, which can be tracked in ocean samples more easily than other elements because helium is nonreactive. Water from deep ocean currents can also be distinguished from air-exposed surface water sources by comparing these ratios, since atmospheric helium ratios are much lower.

Oceans absorb 90% of warming from greenhouse gases

Oceans are providing increasingly more energy to power hurricane intensity. Current projections show rapid intensification is becoming more common, increasing the likelihood of Category 4 and 5 storms.

B2 models the interactions of air, water, soil, plants and microbes at the LEO

The Landscape Evolution Observatory at Biosphere 2 examines how factors such as climate change, water flow, weathering and community development impact landscape structures comprising 500 metric tons of crushed rock. Research is also conducted at biomes representing savannas, mangroves, coastal fog deserts, oceans and rainforests.

NOAA's interactive sea level rise viewer

How will rising seas affect you? Launch NOAA's sea level rise viewer and zoom in on impacts to different parts of the United States, or type in your city or address to learn more.

How scientists study Earth's geocorona, the farthest portion of the planet's exosphere

Seen via ultraviolet radiation scattered by neutral hydrogen in the region, observations by the ESA/NASA Solar and Heliospheric Observatory indicate that the geocorona extends roughly 50 times Earth's diameter above its surface. At this distance, the geocorona extends beyond the Moon's orbit.

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 ozone layer is on track to recover to pre-1980 levels by mid-century

Thanks to the Montreal Protocol, the ozone layer is steadily recovering and, according to a 2022 assessment, is expected to return to 1980 levels by 2040 globally, 2045 over the Arctic, and 2066 over Antarctica.

Explore next-generation geothermal projects worldwide

This tool from the Clean Air Task Force allows users to see the location of geothermal power systems to depths of 12.5 kilometers (7.8 miles), where temperatures reach about 450 degrees Celsius (842 degrees Fahrenheit), including proposed, abandoned, and in-development projects.

The world's largest garbage patch, explained

The Great Pacific Garbage Patch is the largest accumulation of ocean plastic in the world and is located between Hawaii and California. Scientists of The Ocean Cleanup Foundation have conducted the most extensive analysis ever of this area.

Hawaii is the only US state with no incorporated municipalities

Unlike every other state, Hawaii has no cities or towns. Its four county governments manage all local services—the functions that municipalities provide elsewhere in the US—across the entire state.

A breakdown of Earth's atmospheric layers, including why it can get colder or hotter with altitude

Gases in the troposphere—the atmosphere's lowest layer—cool with increasing height as they get farther from the thermal energy emitted by Earth's warm surface. In the next layer—the stratosphere—ozone is increasingly heated by the sun's ultraviolet radiation with height. Because cooler air sinks and hotter air rises, the cooler troposphere and hotter stratosphere form a natural boundary keeping Earth's weather in the lowest layer.

The NOAA has a specialized team of researchers that fly directly into hurricanes

The reconnaissance missions gather data for computer models to forecast hurricanes and improve disaster preparedness. Each flight can last eight to ten hours and uses a specialized Air Force fleet.

Mapping the Tongan eruption impact

A team of scientists—with the help of an uncrewed boat remotely controlled from the UK—join forces to produce one of the clearest pictures to date of what took place underneath the water as an enormous volcano erupted near the Tongan mainland.

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.

Governments around the world are struggling to measure loneliness

Funding for policy resources often hinges on measuring the scale of a problem and then being able to measure the effectiveness of interventions, requiring data. Yet defining and measuring loneliness at a country-scale remains challenging. Typically, the University of California Los Angeles Loneliness Scale is sometimes used worldwide or adapted to measure loneliness.

Brief article explaining why the Amazon rainforest might now produce more carbon dioxide than it absorbs

Climate change and deforestation may have transformed the Amazon rainforest into a net source of planet-warming gases instead of a carbon sink, according to Smithsonian magazine.

As of 2026, the majority of US states have unsafe radon exposure levels

Alaska, South Dakota, Pennsylvania, Ohio, and Washington top the list of states with exposure levels above 4 picocuries per liter for this naturally occurring radioactive gas. While these state-level averages vary from one county, municipality, and home to another, the EPA encourages those in the highest-risk states to test their homes.

An investigation suggests a Scottish island became awash in forever chemicals via seafoam and seaspray—raising questions about what that means for the safety of other coastal areas.

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.

Track the location of the Voyager probes, currently between 13 and 15 billion miles away from Earth.

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 boiling temperature of water decreases with increasing elevation because the molecules need less energy to overcome the lower atmospheric pressure associated with thinner air.

While El Niño moves warm Pacific Ocean waters east along the equator, La Niña moves them west, shifting where rainfall will become more common for months.

This real-time tracking of the hantavirus cruise ship outbreak in May 2026 offers a unique glimpse into the global reach of the outbreak and whether the virus sickened passengers and their communities around the world.

Explore the history, structure, and species of Australia's Great Barrier Reef with this interactive journey narrated by Sir David Attenborough.

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

Massive blooms of microscopic plankton called dinoflagellates produce the neon blue light seen in glowing tides.

Volcanoes 'die' when their supply of magma runs out, if they are shifted away from their underlying magma reservoir, or if they get clogged by collapsing or their magma cooling back into rock.

See the 25 of the best photos of auroras from around the world.

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.

Explore an interactive map built from more than 100,000 survey responses on where people find joy in their lives

The USPS spent $3.97B in 2024, accounting for .058% of the federal budget.

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.

See photos of Meteora, a mountainous site in central Greece, home to 14th-century monasteries perched atop soaring outcroppings.

Double world record holder Hunter Ewen helped conquer his fear of balloons, called globophobia, by training to win Guinness World Record titles for balloon inflation.

While the sun's gravity keeps the planets in orbit, their gravity also pulls on the sun, causing it and everything else in the solar system to orbit around a mutual balance point called the barycenter—the true center of the solar system.

Telehealth demand for GLP-1s for weight loss is booming as consumers seek easier access.

'Grand Canyon of the Yellowstone,' a work by American painter Thomas Moran, inspired Congress to establish Yellowstone National Park.

The US Constitution is widely regarded as the longest-standing written national constitution still in force—see how it has influenced rights worldwide.

Legendary architect Frank Lloyd Wright designed the SC Johnson headquarters in Wisconsin, aiming to make a cathedral-like workplace

One disco producer saw 'Star Wars' four times on its opening weekend and was so inspired that he recorded the album 'Star Wars and Other Intergalactic Funk,' which produced a chart-topping single.