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

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.

Learn why the Montreal Protocol may help prevent millions of cancer deaths

By restoring the ozone layer and reducing ultraviolet exposure, full implementation of the Montreal Protocol is expected to prevent about 443 million cases of skin cancer, 2.3 million skin cancer deaths, and 63 million cases of cataracts among Americans born from 1890 to 2100.

The history of the Montreal Protocol, the only universally ratified treaty in UN history

Mario Molina and F. Sherwood Rowland discovered that chlorofluorocarbons released chlorine atoms that could break down molecules making up the protective ozone layer. Despite attempts to discredit scientists and economic concerns raised by politicians, the agreement to phase out ozone-depleting substances was signed in 1987.

Watch a 1986 television special about the discovery of the ozone hole

The groundbreaking discovery of the Antarctic ozone hole in the mid-1980s marked a critical turning point, galvanizing international action to address the ozone-depleting properties of chlorofluorocarbons, which had been identified about a decade earlier. This environmental crisis was brought vividly to public attention through media pieces like this one.

How a black market for banned refrigerants still threatens ozone recovery and climate progress

Despite the Montreal Protocol's success, illegal trade in chlorofluorocarbons, hydrochlorofluorocarbons, and hydrofluorocarbons persists. Driven by high profits and weak enforcement, smugglers supply banned refrigerants, causing significant ozone depletion and greenhouse gas emissions equivalent to billions of tons of carbon dioxide.

Why the ozone hole altered Southern Hemisphere jet streams and rainfall patterns

Ozone depletion over Antarctica shifted jet streams southward, drying Australia while increasing rainfall in Uruguay, Brazil, Paraguay, and Argentina. Around the turn of the millennium, these trends began to slow as the Montreal Protocol phased out ozone-depleting substances.

How a skin cancerous growth shifted an initially skeptical President Reagan on the ozone crisis

While a 1985 Nature study revealing the Antarctic ozone hole jolted public concern, Reagan's administration was more focused on the Cold War than on environmental policy. His health scare and the market potential for developing alternatives to chlorofluorocarbons helped turn the tide, leading to the Montreal Protocol's unanimous ratification by a bipartisan Senate in 1988.

Track the current size of the Antarctic ozone hole with NASA's real-time data

NASA's Ozone Watch provides daily satellite images and time-lapse videos showing the extent of the Antarctic ozone hole. Each spring, scientists monitor its size and depth to measure recovery progress and detect any new chemical or climatic disruptions.

Hear firsthand how scientists and policymakers saved the ozone layer

In this episode, atmospheric chemist Susan Solomon and Protocol architect Stephen Andersen recount how scientific discovery, diplomacy, and public pressure drove the Montreal Protocol—and share lessons for tackling climate change.

Oxygen and ozone molecules absorb up to 99.9% of UV radiation reaching Earth

Although they make up no more than 10 out of every million molecules in the ozone layer, ozone provides outsized protection by absorbing the most energetic wavelengths of ultraviolet radiation. This absorption increases thermal energy in the stratosphere, causing temperatures there to rise with altitude.

How sunlight helps chlorofluorocarbons destroy the ozone molecules that block solar radiation

CFCs, which are used in old refrigerants, air conditioners, and aerosol sprays, do not react with atmospheric molecules. Once they reach the stratosphere, ultraviolet radiation breaks chlorine atoms off of them, which can each break apart more than 100,000 ozone molecules, thinning Earth's protective layer against ultraviolet radiation.

Arctic permafrost may store twice as much carbon as the entire atmosphere

Rising greenhouse gas concentrations are expected to continue to increase average global temperatures and threaten to thaw ground that has been frozen for thousands of years. The release of greenhouse gases from remnant organic matter would exacerbate the greenhouse effect, creating a positive feedback loop.

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.

From 2023 to 2025, coral reefs experienced their fourth global bleaching event

Heat stress from the 33-month-long event impacted about 84.4% of the world's coral reef area across waters in at least 83 countries and territories, making it the largest such event to date. Due to climate change, about 90% of coral reefs are expected to undergo bleaching annually by 2050, leaving insufficient time for recovery during the winter months between bleaching events.

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.

Climate models have predicted sea level rise almost perfectly since the 1990s

The rise in sea levels is primarily due to melting ice in Greenland and Antarctica, and predicted levels have been confirmed accurate by satellite observations. Ocean currents influence regional variations in sea level rise, which are expected to accelerate.

Butterfly populations have declined by 22% from 2000 to 2020

Research suggests that one in every five butterflies is lost due to pesticide use, habitat loss, and climate change. Playing a vital role in pollination, their declining populations threaten plant reproduction and the health of ecosystems.

Scientists testing how climate change affected plants found in a years-long simulation study that poison ivy grew 70% faster than it did without extra carbon dioxide

The experiments in the 1990s were designed to simulate potential 2050 conditions, using carefully controlled circular forest plots with gas pumped into them.

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.

By 2030, experts estimate a 1 in 1000 chance of a plane being hit by space debris

As more satellites and spacecraft are launched, the rate of space debris re-entering Earth's atmosphere, including those that do not burn up completely, increases. International space agencies and air traffic control systems will need to coordinate to develop standardized methods and technical solutions to prevent and minimize future crisis scenarios.

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.

Aurora-related activities drive significant tourism in regions near the Arctic Circle

As the peak solar cycle approached from late 2024 to early 2026, airlines serving countries such as Iceland, Finland, and Canada increased their scheduled flights, with direct flights to Tromsø, Norway, doubling since 2018. The northern lights tourism market has grown about 10% per year and is expected to increase from $941.9M in 2024 to $1.648B in 2030.

Track where your plastic trash will be in 20 years

This map illustrates the fate of floating plastic 20 years from now. Simply add a location of choice and see the journey unfold.

1 in 15 adults over age 40 experience phantom odors

This phenomenon was measured in a 2018 study that examined the prevalence and risk factors for phantom odor perception. Older adults were less likely to experience these phantom odors as they age, just as their overall sense of smell declines. Women are more likely than men to perceive phantom odors.

The world reached historic levels of democracy under the rules-based order, though that trend has reversed

The share of democracies worldwide grew dramatically from the mid-20th century, reaching an all-time high in the early 2010s. Since then, the trend has reversed, with an increasing number of countries experiencing democratic backsliding.

What revisiting a 1979 experiment reveals about ecosystem recovery after deep-sea mining

A 2023 study co-led by the National Oceanography Centre and the Natural History Museum, London, found that tracks made by the mining vehicle remained largely unchanged since 1979. Small animals, such as amoeba-like xenophyophore, were seen in the cleared areas, but sightings of larger animals known to live in the region were much rarer. (Some readers may experience a paywall.)

The average retirement age by country, visualized

In the US, the average retirement age was 64 as of 2020. The Organization for Economic Co-operation and Development projects a two-year increase in the average retirement age by the mid-2060s.

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.

The use of fungi to detoxify land and water—a process known as mycoremediation—has been used to clean up natural resources affected by the 2025 California wildfires.

Fish populations in the Great Barrier Reef have increased after installing waterproof speakers on the ocean floor that played recordings of sounds from healthy coral reefs.

The hormonal disorder PCOS was renamed PMOS in 2026, a move designed to improve care and research by shifting the focus to the hormonal causes of this condition that affects 1 in 8 women.

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.

In 2026, Finland was named the world's happiest country for the ninth consecutive year based on its wealth, social safety network, and high life expectancy, among other factors.

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

Electrical grids worldwide must double their power delivery capacity by 2050 to meet surging demand from AI and electric vehicles.

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

Indefinite cloning of some endangered species may not sustain their longevity because cloning success rates decrease as genetic mutations accumulate.

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

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

When a Paris department store hesitated to sell Estée Lauder's perfume, she 'accidentally' broke a bottle, causing the smell to spread throughout the store and shoppers to start asking to buy the scent.

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

The 2026 Ebola outbreak in the DRC is spurring new Ebola vaccine development for the Bundibugyo species.

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.

Domino's Pizza's 30-minute delivery guarantee was responsible for the chain's 1980s surge, but it was discontinued after the company was found liable for delivery driver accidents.

The first steps to rebuilding your credit score include getting to know exactly what's on your credit report and figuring out how far you are from the '700 club,' or 'good score' range.

Sunflowers have long been a symbol of nuclear disarmament because they can extract large amounts of radioactive cesium from soil.

In preparation for this weekend's Eurovision finale, which is something like the World Cup of pop music, here's a young Céline Dion performing (for Switzerland?) at the 1988 competition.

Tattoos remain visible on your skin thanks to immune cells called macrophages

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

While atoms are normally made of protons, neutrons, and electrons, exotic ones have been built with antimatter—alternate versions of normal matter that live for fractions of a second and are about a billion times as rare.