How accurate are climate models?

Explore hindcasting on climate models published since 1972

Hindcasting tests model forecasts against observational data to determine their accuracy. In this interactive, you can learn about the differences between eight climate models and evaluate them against available climate data.

What are climate models?

Climate modeling what is a global climate model? What are their uses? Why do we believe them? What do they agree on? Why do they disagree? How do we improve them?

Global climate models simulate Earth system interactions and how human activity impacts climate

By splitting the planet into tiny 3D grid cells, supercomputers can run thousands of equations for each cell to determine the movement of energy, moisture, and other elements across Earth. The equations can also incorporate greenhouse gases to determine how humans affect the climate.

Accurate climate models incorporate calculus to account for complex feedback loops

The simplest models assume uniformity across the Earth, with incoming energy from the sun being offset by the planet's albedo, or reflectiveness, which prevents the radiation from being fully absorbed. Incorporating elements such as atmospheric layers, latitude bands, geographic variability, and emissivity yields coupled differential equations quantifying Earth's interconnected systems.

Climatologists use past data and advanced models to forecast future climate trends

Unlike meteorology, which focuses on weather forecasting over several days, climatology identifies trends in data over periods of 30 or more years. This data can go back millions of years and help refine models to forecast centuries into the future.

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.

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.

Explore Earth's future climate under different levels of warming

An incredible interactive project showing how global warming is projected to affect the world, from temperatures to rainfall, droughts and flooding, and more.

What types of extreme weather can be attributed to climate change?

For decades, it was impossible to say that a specific weather event was caused, or even made worse, by climate change. But advanced research methods are changing that.

AI-powered models can provide low-cost, localized and accurate weather forecasting

These models can run on standard laptops, reducing the need for expensive supercomputers and expanding access to developing regions. AI forecasts can help farmers make informed planting decisions, improving crop yields and reducing costs.

Simulate the effects of government policies on climate projections

The En-ROADS tool lets you role-play as a global decision maker to explore the long-term effects of various policy ideas on climate. More than 341,000 people worldwide, including over 130 members of Congress, have used the simulation.

Explore a series of interdisciplinary explainers on climate science

From animations on the quantum mechanics of greenhouse gases to a photo essay on how scientists acquire climate data, this collection provides detailed explorations of how different branches of science have contributed to our understanding of climatology.

The ratio of stable carbon isotopes in climate proxies provides climate variable data

Measures of the abundance of carbon-13 and carbon-12 can vary in a sample due to environmental and climatic factors. Plants more readily assimilate carbon-12 during photosynthesis, allowing the ratio to serve as a proxy for past conditions that favored plant life.

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.

Scientists have tested atmospheric models by firing rockets into the aurora borealis

Functioning like components of a CT scan, the missiles transmit signals that can be used to identify charged particles and electromagnetic currents in slices. The slices are then combined to construct a computer-based model of Earth's atmospheric structure, which is used to compare the accuracy of physics-based models.

The cone of uncertainty predicts where a hurricane's center can potentially travel

A common misconception is that regions beyond the cone are safe, but the spread does not depict the full reach of a cyclone's wind, rain, or storm surges. The cone is not built from real-time storm data but is an average forecast error from the past five years.

Atmospheric processes amplify the strength of storms by coalescing clouds

Research has shown that turbulent mixing of air at the edges of clouds and other small-scale thermal activity beneath them help clouds group together, intensifying short bursts of rainfall, especially in tropical regions. Simulations reveal this produces more powerful storms than predicted by older models, though they may occur less frequently.

Chaos theory—informally known as the butterfly effect—is the reason why weather forecasts are presented with probabilities rather than certainties.

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.

Tracking the accuracy of past and future predictions of the apocalypyse

Religious figures, scientists, technologists and others have long heralded the ending of the world in what in some traditions is called the apocalypse. This site tracks those failed predictions in the past and charts those coming up in the future.

This flat map is still wrong, but it's the least wrong of all flat maps

While flat maps can never be as perfectly scaled as a globe, they're far more practical than carrying around a sphere. Researchers set out to minimize six major errors of flat maps, including boundary cuts and skewed proportions, by simply squashing...

There are statistically significant discrepancies in measured universal expansion

Using data from the cosmic microwave background, which allows astronomers to model the universe's conditions since its earliest moments, yields a rate of expansion—the Hubble constant—lower than values obtained from multiple techniques measured locally at more recent timescales. Reconciling the discrepancy, known as the Hubble tension, will require a third independent measurement method between the two scales

Large oil companies knew about the impact of carbon emissions since the ’70s

PBS Frontline’s The Power of Big Oil reveals how industry giants like Exxon and Shell were researching climate change in the 1970s but then funded denial campaigns—using internal science to sow public doubt for decades.

There may be 500,000 additional malaria deaths by 2050

Research published in the journal Nature in January 2026 estimates that by 2050, climate change may trigger more than half a million additional malaria deaths and over 100 million additional malaria cases. The work is based on climate change projections and available disease information and did not incorporate new vaccine uptake.

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...

Research suggests articles on Wikipedia are about as reliable as 'accurate' sources

Studies from Nature, The Guardian, the Journal of Clinical Oncology, and the Canadian Library Association, among others, did not identify significant errors, particularly in articles related to academic topics. The site is still considered an exploratory, tertiary source subject to systemic biases from its human editors, especially within controversial topics.

Reported earthquake magnitudes change as more data refines initial estimates

Initial magnitudes are based on limited information, while final magnitudes account for factors like fault size, rupture duration, and seismic wave behavior. Larger earthquakes have the most complex seismic wave activity and often require the most time to finalize recorded magnitudes.

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.

Poison ivy will likely become both larger and more resilient due to climate change.

How the most famous Ebola book, The Hot Zone, which sold 3.5 million copies and was translated into 30 languages, got aspects of the disease so wrong.

Some renewable energy sources may weaken the resiliency of electric grids by removing outage buffers provided by coal- and natural gas-fired plants, which provide the system with more time to find a new power source if a plant goes down.

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

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.

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.

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.

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

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.

Hedge funds, the private investment firms that trade a wide swath of financial assets, make money by imposing steep fees on investors and from the fund's investment performance.

Astronauts have repaired genetic damage in space using CRISPR—a molecular tool that can make precise changes to DNA and is used in single-celled organisms to attack invasive viruses.

In recent years a child anxiety expert has created and tested a novel phobia and anxiety treatment approach for children, focused on changing how parents respond to the fears.

Clever Hans was a 1900s horse that was believed to be able to solve math equations, tell time, and read and comprehend German, until a psychology student discovered how he got his answers.

See how each of the more than two million known species relates to each other—and to common ancestors—in this zoomable tree of life.

The power and influence of the American presidency have expanded significantly over time—far beyond what the founders envisioned.

According to the physics of black holes, our 4D reality may be a hologram—a projection of information coded on a 2D surface on the edge of the universe.

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.

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.

Recent research found that the brain doesn't seem to massively rewire following amputation—upending earlier beliefs about the cause of phantom limb pain.

The syncytiotrophoblast is the outer layer of the placenta and the largest human cell, spanning an area about twice that of a king-sized bedsheet.

Gerrymandering works through two techniques: cracking opposing voters across districts to dilute their power, and packing them into a few to waste their votes in lopsided majorities.

The 19th-century painters of the Hudson River School were among the first American romantics, with portraits that displayed the natural beauty of the young country.