1. Tools of Environmental Science

2. Section 1: Scientific Methods
How do we do environmental science?
Scientific MethodS
The Scientific Method is a Myth!—there is no single scientific method!

3. Experimental Method Observe & Ask Questions Research Hypothesize
Variables
Dependent Variable—DV (DRY)
Independent Variable—IV (MIX)
Groups
Experimental group—gets the IV
Control group—does NOT get the IV
Lab Vs. Field Experiments

4. Collect, Organize, & Analyze Data
Draw Conclusions
Repeat Experiment
Report Results

5. Correlation Method Examining associations between two or more events
Must be careful! Correlation ≠ Causation

6. The Correlation Co-efficient
The correlation coefficient ® measures the strength of association between two variables
INSERT EQUQATION HERE
This value ranges between +1 and -1 and indicates how two factors can vary in relation to each other
If r > 0 as one factor increases, the other factor will increase with it
If r = 0 the two factors are not related
If r < 0 as one factor increases, the other factor will decrease
We must then evaluate whether the r value represents a true association between the variables or whether it is simply due to chance
If the correlation coefficient is significant it indicates that there is a strong association between 2 variables
Find the row for the correct degrees of freedom and determine whether the r value is significant at the 5% or 1% significance level
If df – N – 2
5% chance that we could have gotten that r value due to random chance
1% chance that we could have gotten that r value due to random chance
Significant association does not imply cause and effect
Our value of is not significant
Correlation Between Variables
Scatter plots: can be used to visualize the degree of correlation
Correlation coefficient: measure of association between 2 variables
r = 1 for perfect correlation
r = 0 for no correlation

7. The Correlation Co-efficient
The correlation coefficient ® measures the strength of association between two variables
INSERT EQUQATION HERE
This value ranges between +1 and -1 and indicates how two factors can vary in relation to each other
If r > 0 as one factor increases, the other factor will increase with it
If r = 0 the two factors are not related
If r < 0 as one factor increases, the other factor will decrease
We must then evaluate whether the r value represents a true association between the variables or whether it is simply due to chance
If the correlation coefficient is significant it indicates that there is a strong association between 2 variables
Find the row for the correct degrees of freedom and determine whether the r value is significant at the 5% or 1% significance level
If df – N – 2
5% chance that we could have gotten that r value due to random chance
1% chance that we could have gotten that r value due to random chance
Significant association does not imply cause and effect
Our value of is not significant
Correlation Between Variables
Scatter plots: can be used to visualize the degree of correlation
Correlation coefficient: measure of association between 2 variables
r = 1 for perfect correlation
r = 0 for no correlation

8. Habits of Mind & Quality of Character
Curiosity
Imagination & Creativity
Skepticism
Openness to New Ideas
Honesty
One must exercise limited skepticism
Assumptions of science include: universe is real, senses are accurate, natural laws are knowable and consistent

9. Section 2: Statistics & Models
Statistics is the practice of collecting and analyzing numerical data in large quantities
Mean = average
Distribution = relative arrangement of the members of a statistical population. It’s the ‘shape’ of the curve around the mean.
Relative to the mean!

10. Human height has this type of distribution

11. The shape is determined by the mean and the standard deviation
The shape is determined by the mean and the standard deviation. SD is the square root of variance. Look up the equation for variance

12. Probability—chance that an event will occur
Below is a graph created after rolling 2 dice 100 times. What the chances that you would roll a 7?

13. Statistics in Everyday Life
Examples
Weather
There’s a 50% chance of rain
Climate Change
The average global temperature has increased

14. Risk—probability of an unwanted outcome

15. Models—representations of objects or systems
Physical Model—3D

16. Graphical Model—maps and charts

17. Conceptual Model

18. Section 3: Making Informed Decisions
Decision Making Model
Gather Info
Consider Values
Explore Consequences
Make a Decision
Evaluate the outcomes!
ICED!

20. Case Study: Saving the Everglades
Read the case study on pages 48 & 49
Answer questions 1 & 2