What’s happening?
Our atmosphere contains greenhouse gases (such as carbon dioxide and methane) that absorb heat from the sun. This is good, because it makes our planet warm enough to sustain life. But we are releasing more and more greenhouse gases into the atmosphere these days, and this is causing our atmosphere to absorb more and more heat (global warming). The greater heat is leading to regional and global changes in average temperature, precipitation, wind and ocean currents, and storms. That is, global warming is causing climate change. Also, our oceans are absorbing more carbon dioxide (CO2) from the atmosphere, which reacts with water to form carbonic acid. This makes our oceans more acidic, and this is harmful for ocean life.
What’s causing it?
The earth's climate changes naturally over long periods of time, but the changes we’re seeing now are much faster, and they are caused by things people do. When we burn coal, oil, and gas, or grow pigs and cows for meat, we release greenhouse gases like CO2 and methane into the air. When we cut down trees, we’re taking away plants that otherwise would be absorbing some of the CO2.
What are the consequences of climate change?
As ocean water warms and expands, and as polar ice caps melt, sea levels will rise and flood coastal areas where people live. Changes in average temperature, wind patterns, and ocean currents mean that some parts of the world will get hotter and some will get colder. Many areas will suffer colder lows and hotter highs.
Changes in climate and acid in oceans will affect the habitats where plants and animals live. Many species of plants and animals will not be able to adapt in time and will become extinct.
Changes in precipitation and mountain snow cover will result in many areas having less water, which will make it harder to grow food. Some parts of the world may become drier, while others may have more floods. In some countries people may fight with each other over food, or countries might go to war with each over food and other resources. Many people may become refugees because their homes and land have flooded and they can’t make a living.
We can’t predict exactly what will happen in any one place, but we’re already seeing some bad effects for people, animals, and plants, and we can expect that there will be more. Some changes will take place suddenly, and others will take place gradually over the course of this century and the next.
What can we do?
We can't stop global warming and climate change completely, because the extra greenhouse gases in our atmosphere will continue to cause the planet to warm for awhile. But we can make better choices, individually and together, that will result in less greenhouse gas being released, and this will help make the problem smaller than it would otherwise be. We can also take steps to prepare ourselves and our communities for change. To learn more about what we can do, see our Climate Action for Kids page.