Alternative Models in Earth & Space Science

Instructor: Marc Chiacchio

Marc has taught Bachelor level students climate science and has a PhD in climate science.

In order to investigate a scientific phenomena in the Earth and space sciences, it is important to propose alternative models. In this lesson, we list such models and discuss their appropriateness.

Concepts of a Scientific Model

If you ever wanted to know what the climate or temperature of the Earth would be like in the future, we simply cannot go outside and measure the temperature with a thermometer. It is impossible to have a good idea of the future climate, unless we make a scientific model based on what we already know.

Scientific models are used to explain the real world. Scientists build these models to represent a process or phenomenon and conduct experiments to test them as if it were reality. By conducting such experiments, scientists can control certain aspects of that process or phenomenon, which makes it easier to understand. That is the main goal of using scientific models.

Models in Earth and Space Sciences

Models in science can range anywhere from a 2D model such as a diagram of the Sun, a 3D model such as physical model of a rocket engine, or a mathematical computer program such as a climate model. A model that includes diagrams or flowcharts are called visual models and can be used in a classroom by a teacher explaining important scientific concepts to a classroom or a scientist to another scientist in the lab. Climate models are actually mathematical or computer models that can involve many physical processes.

Physical processes incorporated in a climate model.

Computer models are used in many applications in the earth and space sciences where complex mathematical calculations are used to represent everything we know about a physical process such as the life of our Sun or the evolution of the path of a hurricane that develops in Western Africa and slowly advances towards the eastern Atlantic Ocean. With the these types of models they can help predict the future development of such hurricanes.

However, such models are not perfect and cannot represent all types of processes involved when investigating a physical phenomenon. Models are constantly being changed and improved upon. In some cases additional models must be created. These are called alternative models, which are used to eliminate models that may not represent a physical process that well or one that makes a poor prediction.

Alternative Models

Alternative models have been created to describe and explain given information from Earth and space science. For example, alternative models have been put forth to help explain global warming including natural factors such as solar activity, volcanic eruptions, or the El Nino Southern Oscillation (ENSO) and Pacific Decadal Oscillation (PDO). ENSO and PDO are natural cycles of climate variability occurring in the Pacific Ocean.

Though these processes that have been included in earlier models explain some of the recent warming, they are not successful as those that in addition incorporate human induced causes such as greenhouse gases from fossil fuel emissions. They are not successful because the warming caused by these factors are not enough to explain the rapid increase in global temperature over the past decades. Greenhouse gases are gases contained in the atmosphere that have the ability to trap heat such as carbon dioxide. In this case, it is more appropriate to use alternative models that also include human induced climate change.

Another related example regarding alternative models for conveying information from Earth and space science include two models that try to explain the origin of the universe, which were proposed in the mid-twentieth century. These two models include the Big Bang and the Steady State Theories. The Big Bang Theory involves a beginning to the universe while the Steady State Theory proposes that there is not a beginning or end to the universe. Once the cosmic microwave background was discovered in 1963, it eliminated the need for the Steady State Theory.

To unlock this lesson you must be a 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

Become a member and start learning now.
Become a Member  Back
What teachers are saying about
Try it now

Earning College Credit

Did you know… We have over 220 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? 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
Used by over 30 million students worldwide
Create an account