What Is Climate Change? Definition, Causes and Effects

Children today face three times as many climate disasters as their grandparents did. That’s not a projection—it’s already happening, and it affects everything from the air they breathe to the schools they attend. A 2023 EPA report projects childhood asthma rates could climb by up to 11% if global temperatures rise another 4°C. Since the Industrial Revolution, Earth’s average temperature has risen approximately 1°C, and the pace is accelerating. Understanding what climate change actually means—and what it means for the youngest among us—is the first step toward doing something about it.

UN Definition: Long-term shifts in temperatures and weather patterns · NASA Definition: Long-term change in average weather patterns · Primary Cause: Human activities releasing greenhouse gases · Key Gases: CO2 from burning fossil fuels

Key data points from authoritative sources establish the scope of climate change impacts on children.

“Climate change, therefore, is a change in the typical or average weather of a region or city.”

— NASA Grades 5-8

What is the official definition of climate change?

The United Nations defines climate change as long-term shifts in temperatures and weather patterns. These shifts can be natural—through volcanic eruptions or changes in Earth’s orbit—but since the mid-20th century, human activities have become the dominant driver. The NASA Science team puts it more precisely: climate change is a long-term change in the average weather patterns of a place, region, or the entire Earth.

The distinction between weather and climate matters. Weather is what happens day to day—sunny one afternoon, rainy the next. Climate is the average of that weather over decades. Think of it like your personality versus your mood on any given Tuesday. NASA’s educational resources (NASA Grades 5-8) explain this simply: climate is the usual weather of a place over a long time, such as sunny and warm in Hawaii or cold in Antarctica.

UN Framework Convention

The UN Framework Convention on Climate Change (UNFCCC) draws a legal line between climate variability from natural causes and change attributable to human greenhouse gas emissions. The United Nations explicitly lists the observable effects: hotter temperatures, more severe storms, increased droughts, warming oceans, shrinking ice sheets, and rising sea levels. These aren’t predictions—they’re what scientists already observe.

NASA perspective

NASA’s climate division emphasizes that global warming—the long-term increase in Earth’s average surface temperature—is a subset of climate change. NASA’s educational materials note that Earth’s climate has naturally cycled through warmer and cooler periods over thousands of years. What makes current change unprecedented is the speed and its clear human fingerprint.

“Most scientists say it’s very likely that most of the warming since the mid-1900s is due to the burning of coal, oil and gas.”

— NASA Grades 5-8

“Kids are not little adults. Their health is impacted more directly by climate change.”

— Harvard T.H. Chan School of Public Health

How to explain climate change to kids?

For younger children, the concept is surprisingly simple. NASA defines climate change for grades K-4 as “a change in the usual weather, like more or less rain or warmer temperatures in a place.” That’s it. No jargon, no percentages—just weather behaving differently than it used to.

The planet has already warmed approximately 1°C since the Industrial Revolution, according to National Geographic Kids. For kids, that might sound small, but it’s enough to disrupt weather patterns everywhere.

Simple analogies

The greenhouse gas analogy works well for children. NASA Science for Kids explains that gases like carbon dioxide trap heat from the sun, warming the planet like a blanket traps warmth around your body. More blankets (more CO2) means more warmth. Human activities like burning coal, oil, and gas add too many blankets.

Key facts for children

• Earth’s average temperature has risen more than 1 degree Fahrenheit in the past 100 years (NASA)
• Most scientists say it’s very likely most warming since the mid-1900s is due to burning coal, oil, and gas (NASA Grades 5-8)
• Extreme weather like heatwaves and floods affects farmers’ ability to grow food (Save the Children)

The pattern: children face climate impacts not as abstract statistics but as disrupted daily life—hotter classrooms, flooded neighborhoods, and dangerous air quality days.

What causes climate change?

Two broad categories drive climate change: natural factors and human activities. Earth’s climate has always shifted through natural cycles—changes in the planet’s orbit, solar energy variations, ocean currents, and volcanic eruptions. NASA’s educational resources list all of these as natural causes. But since the mid-1900s, human activities have overwhelmed natural variability.

Human activities

• Burning fossil fuels (coal, oil, gas) releases CO2 and other greenhouse gases
• Deforestation removes trees that absorb CO2
• Agriculture, especially livestock, produces methane
• Industrial processes release additional potent GHGs

NASA Science confirms that changes since the mid-20th century are driven mainly by fossil fuel burning increasing greenhouse gas concentrations. The carbon cycle normally moves CO2 between atmosphere, plants, and oceans. But excess CO2 from human activity—from cars, factories, and power plants—overloads that cycle.

Natural factors

• Volcanic eruptions (can cause short-term cooling)
• Changes in Earth’s orbital position
• Solar energy output variations
• Ocean circulation patterns

The trade-off: while natural factors still operate, they’re no longer the primary driver. The NASA data is clear—most scientists attribute recent warming since the mid-1900s primarily to human activities like burning coal, oil, and gas.

What are the effects of climate change?

Effects span the entire planet. The United Nations identifies these confirmed impacts: hotter temperatures, more severe storms, increased droughts, warming oceans, shrinking ice sheets, and rising sea levels. For children specifically, the health consequences are direct and measurable.

Rising sea levels

Melting ice sheets, glaciers, and ocean warming caused by climate change contribute to sea level rise. NASA Science for Kids explains that as ice melts and water expands, coastal communities face increasing flood risk. The Save the Children organization documents how, in the Solomon Islands, rising sea levels and storms have destroyed homes and crops—the lived reality for children like 16-year-old Junior.

Extreme weather

Climate change intensifies heatwaves, droughts, floods, and storms. Research from Harvard T.H. Chan School of Public Health shows this directly affects children’s daily lives—limiting outdoor play, closing schools, and forcing families to relocate. The data is stark: children today face three times as many climate disasters as their grandparents did.

• More asthma attacks and allergies from poor air quality
• Food insecurity from crop failures
• Mental health challenges from trauma and displacement
• Heat-related illness limiting outdoor activity

What this means: children in hot countries already deal with overheated classrooms that hinder concentration and learning, according to Save the Children. Flooding from climate change could displace or leave homeless 1-2 million+ children.

How can we stop climate change?

Stopping climate change entirely requires cutting greenhouse gas emissions to near zero. This means phasing out fossil fuel burning, transitioning to renewable energy, protecting forests, and changing how we grow food. No single solution exists—it’s a system-wide transformation.

Reduce emissions

• Shift from coal, oil, and gas to solar, wind, and other renewables
• Improve energy efficiency in buildings, vehicles, and appliances
• Protect and restore forests that absorb CO2
• Change diets (less livestock, more plant-based foods)

Global actions

The United Nations leads international efforts like the Paris Agreement, where countries set targets to reduce emissions. Individual actions matter too: walking or biking instead of driving, reducing food waste, and conserving energy at home all add up.

The trade-off: transitioning away from fossil fuels requires investment, policy changes, and sometimes difficult trade-offs between economic growth and environmental protection. But the costs of inaction—measured in children’s health, displaced families, and lost ecosystems—far exceed the costs of transition.

Related reading: wilding pine invasion · wind shear events

Definitions from UN and NASA align closely with those in the Japanese climate change explainer, which details fossil fuel causes and global impacts.

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