Historical Factors of Climate Change

Instructor: Amy Lange

Amy has taught university-level earth science courses and has a PhD in Geology.

Earth's climate has begun to drastically change during our lifetimes. This lesson delves into some of the causes and science of this recent climatic shift.

What is Climate?

While the recent media attention may make climate change seem like a brand new discovery, the climate has been changing for as long as the Earth has been in existence. The topic is so popular now because the climate has begun to change faster and more dramatically than we have previously observed.

So what is climate change? First, let's define climate. Climate is the prevailing weather conditions averaged over a long period of time. For instance, the climate of the Saharan desert is hot and dry, while Seattle is moderate and wet. Many people confuse climate with weather. Weather is the short-term state of the atmosphere in regards to precipitation, pressure, and temperature. For example, a record hot July one year does not mean the climate is changing. However, when we hit record high temperatures over multiple summers in a row, it begins to point toward a changing climate. Remember, climate is weather averaged over a period of time. So when scientists are looking to determine whether the climate is changing, they look at how long new weather patterns have existed.

Humans and Climate Change

We can tell from records, like ice cores, that the earth's climate changed due to natural causes before humans populated the earth. Factors such as the composition of the atmosphere, volcanic eruptions, and solar radiation can all affect not only the temperature of the earth, but also long-term weather patterns. Humans, however, are a unique animal because we have vastly changed the appearance of our environments. We have taken forests and plains and changed them into highways and skyscrapers. As we have been learning over the past few decades, these actions have had consequences for our global climate.

The Industrial Revolution and Greenhouse Gases

Factories during the Industrial Revolution popularized the widespread use of fossil fuels.
Factory during Industrial Revolution

Scientists see the beginning of the Industrial Revolution in the 1700s as an important turning point in Earth's climate. During the Industrial Revolution, humans transitioned from agrarian jobs to working in factories and industrial settings. These booming factories were burning record amounts of coal and fossil fuels, thereby releasing huge amounts of gases like carbon dioxide, methane, and nitrogen oxide into the atmosphere. Those gases are important greenhouse gases. Greenhouse gases are gases in the atmosphere that are extremely efficient at absorbing solar radiation and slowly releasing it.

Earth
energy budget cartoon

Before we get into the greenhouse effect, let's quickly review Earth's energy balance. So incoming solar radiation from the sun enters the earth's atmosphere. This radiation is either reflected back to space by clouds and snow, or it is absorbed by the earth's land, water, and air and then radiated back to space. Higher greenhouse gas concentrations mean that more heat is being held in the atmosphere instead of being released into space. Therefore, increasing greenhouse gas concentrations in the atmosphere raise the overall temperature on earth. The greenhouse effect is similar to placing plastic wrap over a hot casserole to keep it warm: heat is released into the air until you trap it with an impermeable layer.

Greenhouse gas concentrations over time. Notice the dramatic increase beginning about 1750.
graph of greenhouse gases over time

Ever since the Industrial Revolution, we have used fossil fuels in our cars, power plants, and in the transport of goods. These activities continue to release greenhouse gases like carbon dioxide, methane, and nitrogen oxide into our atmosphere. In fact, carbon dioxide concentrations have increased 40% and methane concentrations have increased 250% compared to the pre-Industrial Revolution era.

To unlock this lesson you must be a Study.com Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use Study.com

Become a Study.com member and start learning now.
Become a Member  Back
What teachers are saying about Study.com
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? Study.com has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create an account
Support