Tools of Tools of Environmental Environmental ScienceScience

2-1Scientific Methods2-1Scientific MethodsObjectivesObjectives

1.1. List and describe the steps of the List and describe the steps of the experimental method.experimental method.2.2. Describe why a good hypothesis is not Describe why a good hypothesis is not simply a guess.simply a guess.3.3. Describe the two essential parts of a Describe the two essential parts of a good experiment.good experiment.44.. Describe how scientists study subjects in Describe how scientists study subjects in which experiments are not possible.which experiments are not possible.55.. Explain the importance of curiosity and Explain the importance of curiosity and imagination in science.imagination in science.

Scientists make most Scientists make most discoveries using the discoveries using the scientific method.scientific method.

Steps in the experimental Steps in the experimental methodmethod

1. Observations1. Observations

2.2. Hypothesis and predictionHypothesis and predictionHypothesis – a testable explanation for an Hypothesis – a testable explanation for an

observationobservationPrediction – a logical Prediction – a logical statement about anstatement about an hypothesis – explains hypothesis – explains what will happen in awhat will happen in a specific situationspecific situation

3.3. Experiment – procedure designed to Experiment – procedure designed to test a hypothesistest a hypothesis

Two groups:Two groups: ExperimentalExperimental – test group – test group ControlControl – conditions are kept – conditions are kept

the same for comparison to the same for comparison to experimental groupexperimental group

variables cause changes you variables cause changes you observeobserve

Types of variables:Types of variables: Independent variableIndependent variable- what - what

is being manipulatedis being manipulated Dependent variableDependent variable- results - results

from change in the from change in the independent variable; what independent variable; what you measureyou measure

4.4. Collect and analyze dataCollect and analyze data-using tables and graphs-using tables and graphs

5. 5. ConclusionConclusion analyze data, hypothesis analyze data, hypothesis

correct?, sources of error, correct?, sources of error, etc.etc.

Revise as necessaryRevise as necessary

6.6. Repeat it!Repeat it! makes it more reliablemakes it more reliable

7. Communicate7. Communicate PublishPublish

Correlation MethodCorrelation Method- Used when questions can’t be - Used when questions can’t be

studied experimentally or studied experimentally or ethicallyethically

- Uses associations between Uses associations between events to answer questions events to answer questions

i.e. tree rings and droughtsi.e. tree rings and droughts

How to practice good How to practice good sciencescience

Be curiousBe curious Be skepticalBe skeptical Be open mindedBe open minded Be honest about results – good or badBe honest about results – good or bad Use your imaginationUse your imagination Be creativeBe creative

2-2 Statistics and Models2-2 Statistics and ModelsObjectivesObjectives1.1. Explain how scientists use statistics.Explain how scientists use statistics.2.2. Explain why the size of a statistical sample is Explain why the size of a statistical sample is

important.important.3.3. Describe three types of models commonly Describe three types of models commonly

used by scientists.used by scientists.4.4. Explain the relationship between probability Explain the relationship between probability

and risk.and risk.5.5. Explain the importance of conceptual and Explain the importance of conceptual and

mathematical models.mathematical models.

How scientists use Statistics How scientists use Statistics - Collections of data that are in Collections of data that are in

the form of numbers; Used to the form of numbers; Used to summarize, characterize, summarize, characterize, analyze, and compare dataanalyze, and compare data

Used to look at statistical Used to look at statistical populationspopulations

Mean - # of individuals/total – Mean - # of individuals/total – averageaverage

Distribution – relative Distribution – relative arrangement of numbersarrangement of numbers

i.e. bell shaped curvei.e. bell shaped curve

Probability – the chance Probability – the chance something will happensomething will happen

Sample - Group of Sample - Group of individuals/events selected to individuals/events selected to represent the populationsrepresent the populations- shouldn’t be too small- shouldn’t be too small

How do we use statistics??How do we use statistics?? Understanding the newsUnderstanding the news

Weather predictionsWeather predictionsFloods, hurricanesFloods, hurricanesEarthquakesEarthquakesSporting eventsSporting eventsGraduations ratesGraduations rates

Thinking about riskThinking about riskRisk – probability of unwanted Risk – probability of unwanted

outcomeoutcome

ModelsModelsRepresent objects or systemsRepresent objects or systemsTypes:Types: PhysicalPhysical Graphical (maps, charts)Graphical (maps, charts) Conceptual (graphical representation of Conceptual (graphical representation of

how system works – flow charts)how system works – flow charts) Mathematical- equationsMathematical- equations

2-3 Making Informed 2-3 Making Informed DecisionsDecisions

ObjectivesObjectives1.1.Describe three values that people Describe three values that people

consider when making decisions about consider when making decisions about the environment.the environment.

2.2.Describe the four steps in a simple Describe the four steps in a simple environmental decision-making model.environmental decision-making model.

3.3.Compare the short-term and long-term Compare the short-term and long-term consequences of two decisions regarding consequences of two decisions regarding a hypothetical environmental issue.a hypothetical environmental issue.

Decision Making ModelDecision Making Model ResearchResearch Consider values (principals Consider values (principals

we consider to be important)we consider to be important) Consider consequencesConsider consequences Make your decision!Make your decision!