the tools of environmental science how do we make decisions?

THE TOOLS OF ENVIRONMENTAL SCIENCEHow do we make decisions?

The Scientific Method

• The basis of scientific discovery is the scientific method.• Also known as the experimental method.

• The first step in the scientific method is observation. This is the process of gathering information, both from the natural environment and from prior research.

• We use observation to find problems, and to form possible answers to those problems.

The Scientific Method• A hypothesis is a testable solution, explanation or

idea. We form hypotheses from the observations we made previously.

• Important points:• Hypotheses must be testable, whether by a

controlled experiment, or through interactions and observations.

• A quality hypothesis is based off of good research and planning.

• Each hypothesis should also have a prediction – an idea of what will happen if the hypothesis is supported.


• For instance, if our hypothesis is that chemical X is harmful to a ladybug population…

• Our prediction could be that areas without the presence of chemical X would have greater numbers of that ladybug.


• For most people, scientific research is tied to quantitative studies. This means that we focus on data and empirical (objective) data.

• An experiment is a procedure or process that tests a hypothesis under carefully controlled conditions.

• Good experiments have two critical qualities:• Only ONE condition should change across study

groups. We call this a variable.• A control group is used, which does not have any

contact with the experimental variable.


• As described above, every quality experiment must have a control group. This is a group that is not associated with the experimental variable in any way.

• Any group associated with the experimental variable is called an experimental group. There can be more than one experimental group in any one experiment.


• In contrast to quantitative studies, we can also use qualitative studies. Qualitative studies focus on subjective observations and insights, as opposed to objective data.

• Knowing this, why would we use qualitative studies?


• Qualitative research is useful for examining issues that cannot be effectively analyzed with empirical data.

• Some examples:• Why and how decisions are made and carried out.• Why and how people cope with various issues in their

lives.• Why and how people are adjusting to changes in their

lives, at home and work/school.


• Qualitative research does not use experiments.

• Instead, researchers observe subjects of research in their natural environment.• Commonly used by

psychologists, sociologists, and anthropologists.


• Regardless of the type of research conducted, the purpose is always to gather data, information relevant to the topic of research.

• All data that is collected must be organized. Tables and graphs are commonly used to easily show and highlight trends found in data.


• We analyze the data obtained in our research, and we use it to come to a conclusion, or a judgment on what our research shows.


• It’s important to note, though…that our research results might not conclusive.• This means that we

cannot come to a definitive judgment as to what the data says.

• This is why quantitative research works better with large sample sizes.

• Note that qualitative research does NOT produce empirical data, so large samples are not needed.• In fact, smaller sample

sizes are preferred, so that researchers can focus tightly on a few subjects.


• One other important thing to keep in mind about conclusions…

• You cannot totally prove or disprove a hypothesis based on just one research project.• Instead, we state that our hypothesis was supported or

not supported.

• It takes many, many repeat trials to definitively prove or disprove a hypothesis or thesis.

• This is why it is so important to publish and communicate your work – so that others can repeat your project.


• Correlative studies are designed to examine the associations between two events. These are useful for examining trends that cannot be experimentally tested, or that would be unethical to do so.

• Examples:• What were some causes of the Permian extinction?• Is cigarette smoking linked to high blood pressure?

• Note, however, that correlative studies do NOT prove cause-and-effect; only relation.

The Scientific Method• There are several habits that are valuable to develop as a scientist.

• Be curious: Always be aware of what is happening around you, you may learn or realize something new.

• Be skeptical: Have the courage to question things we take for granted today.

• Be intellectually honest: Always be willing to question your results, no matter how valuable they are to you.

• Be creative: There are many problems and challenges that just need a change of perspective to be solved. Don’t be afraid to think outside the box.