Unit 1

1. Unit 1 The nature of science

2. Objectives (LT) • Compare areas of study in Earth Science • Identify Earth’s systems • Explain relationships among Earth’s systems • Explain why technology is important to you

3. Section 1.1 • What does Earth Science encompass? • 5 areas of study • Astronomy • Meteorology • Geology • Oceanography • Environmental science

4. astronomy • Study of objects beyond Earth’s atmosphere • Scientists called Astronomers • First viewed using only eye sight • Saw objects such as Sun, Moon and Stars • Objects moved and were tracked over time • First calendars developed from these observations • Technological breakthrough • Telescopes • Saw greater detail • Piqued man’s curiosity • Eventually drove mankind to explore beyond Earth

5. Meteorology • Study of forces and processes that cause atmosphere to change and produce weather • Atmosphere is 100 km thick! (60 miles) • Scientists called meteorologists • Attempt to predict (forecast) weather • See on TV every night • Important to know weather for business • Farming, roofers, shipping at sea, etc. • Weather affects and shapes climate

6. Geology • Study anatomy of earth: • Crust—outer layer • Mantle—molten magma beneath the crust • Core—center of earth • Study of material that makes up Earth • Study of processes that form and change these materials • Scientists called geologists • Study of history of planet and life forms • Identify • Minerals • Rocks • Forces that change and alter these materials

7. Structure of solid Earth Crust—outer layer of lighter rocks---10-60 km thick Mantle—made of heavier rocky material—2900 km thick ---magma located here—molten material Outer core—2000 km thick—made of liquid iron and sulfur Inner core---2800 km diameter—solid iron and nickle

8. Oceanography • Study of Earth’s oceans • Cover ¾ of Earth’s surface • Scientists called Oceanographers • Study/observe • Creatures that inhabit seas • Physical and chemical processes that affect oceans • Track and map ocean currents • Map ocean floor and measure depth • Research affects of oceans on weather and climate

9. Environmental Science • Study of interactions of organisms and their surroundings • Scientists called environmentalists • Be careful—not all “environmentalists” are scientists!! • Study how organisms affect their surroundings • Both positive and negative • Topics studied • Natural resources • Minerals, oil, natural gas, water, soil for farming • Pollution • Impact, if any, of humans on atmosphere

10. Technology • Application of scientific discoveries • Makes life easier and safer • Examples: • Freeze dried food • Calculator • Internet • Smoke detectors

11. Objectives (LT) • Define scientific method • compare and contrast independent and dependent variable • Define “good” experimental design • Know base measurements used in SI • Convert one measurement into another in the same base unit • Identify difference in mass and weight • Know and calculate derived measurements • Convert “normal” numbers into scientific notation

12. Section 1.2 • Methods of Scientists • Scientists are problem solvers • use something called Scientific Method • Observe problem • Hypothesize explanation • Consists of if—then statement • Design and conduct experiment • Conclude if hypothesis was correct or incorrect • Report results to scientific community for review

13. Observation • Gather background information on problem • Research other experiments • Define the problem • Make sure the problem is real

14. Hypothesis • Consists of an IF – THEN statement • This statement will define the experimental design • If this variable is changed (independent) then this result (dependent) will happen

15. Experiment • Organized procedure • Observe and make measurements that test hypothesis • 2 types of experiments • Qualitative • Simply observe and describe using words what was observed • Quantitative • Measurements taken using instruments • Balance, ruler, thermometer, etc. • Good experimental design consists of:

16. Good experimental design • A good experiment tests only one thing at a time called a variable • 2 types of variables • Independent • What is controlled by the experimenter • Dependent • What changes because of the independent variable • Control—identical setup to refer back to • Needed to measure change

17. Conclusion • Analyze data from the experiment to determine if hypothesis was correct or incorrect. • If hypothesis correct the experiment is repeated many times then submitted for peer review • If hypothesis incorrect go back and change hypothesis • All experimentation leads scientists to the truth!!!

18. Scientific method • Easy to remember: • O----observation • H----hypothesis • E----experiment • C----conclusion • Do you see it?? OHEC

19. Measurement • All scientists use the same system of measurement: Metric system!! Called system international (SI) • Length—meter (m) • Mass—kilogram (kg) • Different than weight!! ( weight determined by gravity) • You have different weight on moon than earth! • You have same mass!! (you have same number of atoms in both places) • Time—second • Temperature—kelvin scale—but we will use celcius (oC)

20. Derived measurements • Area • Length x width = area • m x m = m2 • Volume • Length x width x height = volume • m x m x m = m3 • Liquid measurements usually in milliliter or liter • 1 ml = 1 cm3 • Density • Mass/volume • g/ml or g/cm2 or kg/m3

21. Scientific notation • Used to write very large or very small numbers • Accomplish by moving decimal point • Example: 4,000,000 = 4 x 106 .000004 = 4 x 10-6

22. try some scientific notation problems • 100 = 1 x 102 • 2,345,678 = 2.345678 x 106 • .01 = 1 x 10-2 • .2345678 = 2.345678 x 10-1

23. Objectives (LT) • Explain why precise communication is crucial to science • Compare and contrast scientific theories and laws • Identify when it is appropriate to use a graph or a model

24. Section 1.3 • Communication in science • Must be truthful and ethical • Accomplished by peer review • Peer review is when other scientists read your experiment and results then try to reproduce them • You will report your results to me in lab reports • Lab reports will consist of • Hypothesis—if then statement which defines the experiment • Observations (written words—qualitative) • Measurements (numbers with units—quantitative) • Graphs if necessary—picture form of data • Conclusions—was hypothesis correct or incorrect

25. Graphs • Used to show relationships between data • Different types of graphs • Line graph • 2 variables plotted • X-axis = independent variable • Y-axis = dependent variable • circle graph (pie graph) • Used to show fixed quantity • Entire circle = total quantity • Slices = percentage of whole • Bar graph • Vertical representation of quantitative data

26. Models • Scientific model is an “idea picture”, system or mathematical expression that represents concept. • You use models all the time when explaining a situation or experience to your friend when they were not present at the event. You use words such as: like, remember when, etc. • Models change when new information discovered

27. Scientific theory vs. law • Scientific theory is explanation based on many observations from many experiments over a long period of time. • May change if new information discovered • Scientific law is a rule of nature that cannot be broken. It is really a theory that has NEVER BEEN WRONG—OVER HUNDREDS OF YEARS.

28. Review of chapter • Complete ch.1 study guide in text pgs. 22-25 • Complete study guide handout from instructor