Additional Sci Method Reading

Scientific Method

Scientists use the scientific method to answer questions. The scientific method is a series of steps that help to investigate a question.

Often, students learn that the scientific method is a linear process that goes like this:

• • Ask a question. The question is based on one or more observations or on data from a previous experiment.

  • Do some background research.

  • Create a hypothesis.

  • Do experiments or make observations to test the hypothesis.

  • Gather the data.

  • Formulate a conclusion.

The process doesn’t always go in a straight line. A scientist might ask a question, then do some background research and discover that the question needed to be asked a different way, or that a different question should be asked.

A flow chart of how science works that is much more accurate than the simple list above is found here: http://undsci.berkeley.edu/lessons/pdfs/complex_flow_handout.pdf.

Ask A Question

Now, let’s ask a scientific question. Remember that it must be testable.

We learned above that average global temperature has been rising since record keeping began in 1880. We know that carbon dioxide is a greenhouse gas. Greenhouse gases trap heat in the atmosphere. This leads us to a question:

Question: Is the amount of carbon dioxide in Earth’s atmosphere changing?

This is a good scientific question because it is testable.

Atmospheric carbon dioxide has been increasing at Mauna Loa Observatory in Hawaii since 1958. The small ups and downs of the red line are seasonal variations. The black line is the annual average.

How has carbon dioxide in the atmosphere changed over those 50-plus years? About how much has atmospheric CO₂ risen between 1958 and 2011 in parts per million?

Answer a Question

So we’ve answered the question using data from research that has already been done. If scientists had not been monitoring CO₂ levels over the years, we’d have had to start these measurements now.

Because this question can be answered with data, it is testable.

Vocabulary

• • greenhouse gas: Gases such as carbon dioxide and methane that absorb and hold heat from the sun’s infrared radiation in the atmosphere.

  • scientific method: A means of investigating a testable question using empirical information gathered from experiments, experience, or observations.

Summary

• • Scientists use scientific method to answer questions about the natural world.

  • First, scientists ask a question that they want to answer.

  • Background research is essential for better understanding the question and being able to move to the next step.

Practice

Use this resource to answer the questions that follow.

http://www.schooltube.com/video/f52dc16d06d58ede92d5/writing-scientific-questions

1. What is the first rule of writing science questions?

2. What is rule number 2?

3. What type of questions should NOT be used?

4. What is rule number 3?

5. Write a good scientific question using the three rules.

http://www.ck12.org/concept/Scientific-Method/