Human activities are making the Earth hotter, which is affecting people, animals, and nature. Things could get worse in the future, but acting now can help reduce the damage.
Every decade since the 1980s has been warmer than the last. The 11 hottest years ever recorded have happened since 2015. In 2024, Earth hit its highest temperature on record, mainly due to human activity. That year was also the first to go over 1.5C warmer than pre-industrial times. Even in 2025, temperatures stayed high despite a small natural cooling effect called La Niña.
How Humans Are Causing It
The Earth’s climate has always changed naturally, but the fast warming in the past 100 years is mostly caused by humans.
Burning coal, oil, and gas for energy releases greenhouse gases like carbon dioxide (CO2). These gases trap heat around the Earth, making it warmer. Since the Industrial Revolution, CO2 levels have risen by over 50%, far higher than in recent history.
Effects We Are Already Seeing
Climate change is causing real problems today:
- Hotter heatwaves and heavier rainstorms
- Melting glaciers and rising seas
- Shrinking Arctic ice
- Warmer oceans that fuel stronger storms and harm sea life
Extreme weather is already expensive and deadly. For example, the Los Angeles fires in January 2025 may cost over $100 billion. Scientists say climate change made the hot, dry conditions worse.
In 2022, East Africa faced its worst drought in 40 years, putting more than 20 million people at risk of hunger. Climate change made such droughts far more likely. Vulnerable communities suffer the most.
Why 1.5C Matters
The hotter the Earth gets, the worse the effects. Nearly 200 countries have promised to limit warming to 1.5C above pre-industrial levels.
Even 1.5C warming will cause problems, but 2C or more would be much worse:
- More people exposed to extreme heat
- Higher sea levels
- Food shortages in some regions
- Spread of diseases like dengue
- Loss of species and coral reefs
Limiting warming to 1.5C can also prevent dangerous “tipping points” like the collapse of Greenland’s ice sheet or the Amazon rainforest.
