What Is Climate Change?

Lesson Plan - Get It!

Audio:

Take a look outside right now.

• Is it sunny today or cloudy?
• Is it raining or snowing?
• Do you think it is the same all over your country? What about the world?

Weather Versus Climate

What you are observing at this moment is weather: conditions of the environment at a specific place.

Weather events like rain, snow, and thunderstorms are short-lived. They could last for a few days or even just a few hours. Weather patterns differ from one place to another.

Some people use weather and climate interchangeably, but these terms are different. Climate is not two days of rain nor a week of cloudy days.

The environmental condition described by climate covers a huge region of the planet and lasts for a longer period of time. The length of time considered is years, usually 30 years or more. That's a long time, indeed!

Therefore, if you live in the southern part of a state like Florida, where the climate is generally warm, you will also experience some changes in weather patterns such as cloudy skies, rain, and thunderstorms.

Check out What is the difference between weather and climate?, from the National Ocean Service, for a quick rundown.

Climate Change and Its Causes

• What is climate change?

Now that you know how climate differs from weather, let's take a look at the term climate change.

Every location on the earth has average weather patterns that are typical for long periods of time. Climate change describes significant changes in these weather patterns that last several decades or even more.

These changes include, but are not limited to, regions becoming drier, receiving more rain than usual, or getting colder.

• How do we know these changes are happening if it takes a long time to observe?

Sophisticated data-gathering systems from satellites and meteorological stations are able to make sense of these patterns in real-time using automation.

There is also a lot of evidence that can be found on the surface of the earth that reveals a location's climate over time. These include tree rings, sediment in lakes, the shape of our landscapes, the depth of the ocean, and many more.

Watch Climate Change 101 with Bill Nye | National Geographic:

• What causes climate change?

The sun's rays travel through the earth's atmosphere to reach the planet's surface and warm it up. Naturally, this heat is reflected off the surface and back into space, which cools the earth down.

However, some of the heat is not able to escape back into space because it becomes trapped. This trapped heat increases the overall temperature across the entire planet, which leads to a change in climate across the entire planet over a period of time.

To better understand the factors scientists suggest cause climate change, watch Causes and Effects of Climate Change | National Geographic:

Human Impact

Many of the gases released into the atmosphere come from burning fossil fuels like coal, oil, and gas to generate electricity and heat.

Emissions from transportation have contributed to the number of harmful gases in the atmosphere as well.

Deforestation by logging, clear-cutting, and fire releases carbon, which is a component of carbon dioxide that keeps heat from escaping the earth's surface.

Other human activities, such as the use of pesticides, construction, and conversion of agricultural lands to favor urban cities, increase the trapped heat as well.

Natural Causes

Not all sources of carbon and harmful gases are human-generated. Volcanic eruptions, for example, release tons of carbon that mixes in the air and stays afloat for a longer period of time.

The intensity of the sun's heat energy reaching the surface of the earth could also be a factor.

Although natural causes certainly contribute to climate change, they do so on a smaller scale and at a much slower rate.

Think back to your warm and toasty home with insulated walls and windows that trap the heat you generate and keep it from escaping.

The thick layers of harmful gases in the earth's atmosphere act like these wall insulators and trap the heat around the surface of the earth. If it stays too long, it affects the usual weather patterns in most regions.

The Effects of Climate Change

Climate change discussions all over the world are focused on how to minimize human contribution.

The effects of climate change are projected to have significant impacts on the quality of water we drink, the places we live, and the air we breathe. Some of the most notable events attributed to climate change include:

Rising Ocean Levels

Melting ice and rising sea levels have been observed over the last few decades.

Projections indicate that the melting of ice sheets in the Arctic is fast enough to raise the water level by four to six feet in a few years.

Many islands in the middle of the ocean are already seeing its effect on their landscape.

Rising Ocean Temperatures

The extra heat is absorbed by the large bodies of water on the earth's surface, creating warmer and more acidic oceans.

When the temperature rises and the water has more dissolved chemicals, a diversity of aquatic plants and animals face a major threat to their survival.

Extreme Weather Events

Extreme weather conditions are prevalent in some areas of the world. The rising temperature of the earth's surface affects the air circulation and pressure, which results in more violent winds, hurricanes, and thunderstorms.

The devastating effects of these natural disasters have a huge impact on vulnerable communities.

Any change to climate is a global issue with huge ramifications for everyone.

There are people who do not beleive that human impact is the driving force behind changes to our planet's climate. However, all the information available indicates that our climate is changing too quickly.

Scientists believe it is important to rethink our practices to make sure we all have clean water and air, and a decent Earth on which to live!

Move on to the Got It? section whenever you're ready!