Weather vs. Climate
Weather refers to the state of the atmosphere over several minutes up to several days. It includes lots of things that should be familiar - temperature, humidity, rain, snow, wind speeds, or wind direction. Climate refers to the long-term average (and other statistics) of weather measured over long periods of time (at least several decades).
Here’s a simple way to think about it: Climate is what you expect, but weather is what you get. Say you were going to visit Southern California for a few days in April. You would expect it to be sunny and pleasant, because that’s what the climate of Southern California is usually like in April. It might turn out to be sunny during your trip, or it could rain, be cloudy, chilly or hot. All of those are examples of the weather during those few days.
The C2ES Kids Corner is designed to help you understand how and why our climate is changing, how climate change affects us, and what people can do to slow climate change and prepare for it.
We’ll explain the science behind climate change, the impacts of climate change, and how you can help.
The Greenhouse Effect and Climate Change
The picture below shows the greenhouse effect. It is a natural process that warms the planet. Light from the sun passes through the atmosphere and is absorbed by the Earth's surface, warming it. Greenhouse gases, like carbon dioxide, act like a blanket, trapping heat near the surface and raising the temperature.
Human activities are increasing the amount of greenhouse gases in the atmosphere. This traps more heat. In other words, as we add more greenhouse gases, we thicken the blanket that traps heat near the surface. This process is referred to as the human-induced greenhouse effect.
Greenhouse gases stay in the atmosphere for a long time. Although plants and the ocean absorb carbon dioxide, they can’t keep up with all the extra carbon dioxide that people have been putting into the atmosphere. So the amount of carbon dioxide in the atmosphere has been increasing over time.
Source: National Park Service
Where do greenhouse gases come from?
Up until about 150 years ago, human activity did not produce many greenhouse gases. That changed as many important inventions and industrial innovations, like the widespread use of electricity and cars, transformed the way we live.
These inventions and innovations demand energy. Burning fossil fuels — coal, oil, and natural gas — became an important source of that energy. Burning fossil fuels releases carbon dioxide and other greenhouse gases into the atmosphere.
Although there are a lot of different greenhouse gases, carbon dioxide is the most important one that is produced by human activities. It is responsible for most of the “thickening of the blanket” that has trapped heat near the surface in recent decades.
Today in the United States, electricity generation is the largest source of carbon dioxide. It is responsible for nearly 40 percent of emissions. Transportation -- cars, trucks, trains, boats and airplanes – contributes a little more than 30 percent of carbon dioxide emissions. The rest come from industry, such as factories that make products we use, and from energy we use in our homes and businesses.
The Earth is warming. Thirteen of the 14 warmest years on record have all occurred since 2000. If we keep releasing greenhouse gases into the atmosphere, it will continue to warm. This warming brings an increased risk of climate impacts that include:
Heat waves. Heat waves are long periods of time with above-normal temperatures. As the Earth warms, more areas will be at risk for extreme heat waves. Learn more about the link between climate change and extreme heat.
Heavy Precipitation. Heavy downpours are becoming more common in many locations. Learn more about the link between heavy precipitation and climate change.
Sea Level Rise. Sea level has risen about 8 inches in the last century, making coastal storms more damaging. Scientists believe sea levels in the United States could rise 1 to 4 feet in the 21st century, and could be even higher if glaciers in Greenland or Antarctica melt especially quickly.
Threats to habitats and animals. As temperatures warm, many plants and animals have been migrating to higher elevations or toward higher latitudes. Some animals may have difficulty moving to or adapting to new habitats.
Ocean acidification. Extra carbon dioxide in the atmosphere is absorbed by the oceans, making them more acidic. This can make it difficult for corals and microorganisms that form shells to survive.
Arctic melting. Arctic temperatures are increasing at about twice the rate of the rest of the world. Because of this, the amount of ice that covers the Arctic Ocean during the summer has been shrinking.
Wildfires. These are large fires that burn vast amounts of forests and brush. When they are not controlled, wildfires can destroy homes and be deadly. The number of large wildfires and the length of the wildfire season have been increasing in recent decades. Find out how climate change will worsen wildfire conditions.
Drought. Global warming will increase the risk of drought in some regions. Also, warmer temperatures can increase water demand and evaporation, stressing water supplies. Learn about the links between climate change and drought.
These impacts are already happening in many places around the world and will likely grow worse over time as warming continues.
How can people slow warming and prepare for climate change?
There are two things we need to do:
The first is to reduce the greenhouse gas emissions responsible for climate change. We need to find ways to make energy that produce fewer greenhouse gas emissions. We also need to make those energy sources as inexpensive and easy to use as fossil fuels.
One way to reduce emissions is by using less energy, or using energy more efficiently. We can drive cars that use less gasoline or run on electricity or other alternative fuels. We can also use less energy in our homes, offices, and schools. Everyone can play a part in becoming more efficient, including government, businesses, and people like you. We'll talk about some things you can do to use less energy in the next section.
The second is to prepare for life in a changing climate. We need to make sure our buildings, roads, businesses and all the services they use can withstand the climate changes that we can’t avoid.
What can you do to help?
There are lot of things you can do to save energy and help stop global warming, like turning off the lights when you leave a room, taking shorter showers, and recycling. Now that you have some examples, you might be able think of your own ideas! Our Make an Impact program has a list of more things kids can do.
Want to learn more?
Koshland Science Museum: EarthLab
EPA Climate Change Website
EPA Kids Climate Change Website
National Climate Assessment