Scientific Method

Thoughts on the Scientific Method in the Context of Earth Science Projects

Scientists follow various steps when they do science. These steps are loosely called the scientific method, and they can be easily followed. In fact, anyone who has experimented with recipes in a kitchen or at a camp fire has followed some of the key steps of the scientific method.The most common version of the scientific method begins with a question. A cook might wonder if a particular dish will look and taste better if certain ingredients are added to the recipe. A scientist might ask if airplane contrails block enough sunlight to affect weather. Or can a satellite measure the ozone layer better than instruments on the ground?

Scientists (and cooks) then design experiments to answer their question. They then collect data. Sometimes they collect related data that is unaffected by the question they want to answer. For example, when investigating whether or not contrails reduce the temperature at the ground, it is necessary to measure the ground temperature within and away from the shadows of contrails. The latter temperature is known as a baseline, reference or control. Comparing the temperature in the shadow of the contrail with the control temperature allows the scientists to determine the impact of the contrails on temperature.

Keep in mind, when exploring Earth System Science, that it may not be possible to have a control. There is only one Earth! However, attention should still be given to what can be controlled.

After sufficient data are collected, scientists analyze it and make conclusions about their findings using basic statistics and their scientific judgment. Finally, scientists write a report or scientific article about their findings.

Some scientists begin their research by stating a hypothesis, a guess about what their research might uncover. Here’s an example of a hypothesis: Because contrails block direct sunlight, it is likely that abundant, spreading contrails will reduce daytime temperatures at the surface.

The scientist who begins a research project with a hypothesis then follows the same steps given above.Science fair rules often require that students list a hypothesis for their project. For example, the Intel Science and Engineering Fair suggests that students first state the question they are pursuing and then give a hypothesis about the expected outcome. While this procedure is sometimes followed by professional scientists, the hypothesis step is usually not included.

Many very successful research efforts and citizen science or student projects are based on curiosity-or interest-driven observation; that is, on a question that occurs to an observer.

“Why the Scientific Method?” by Richard D. Storey and Jack Carter, THE SCIENCE TEACHER, December 1992, pp. 18-21.