1. Introduction to Earth Science Section 1 SECTION 1: WHAT IS EARTH SCIENCE? Preview  Key Ideas Key Ideas  The Scientific Study of Earth The Scientific Study of Earth  Earth Sciences Earth Sciences  Branches of Earth Science Branches of Earth Science  The Importance of Earth Science The Importance of Earth Science

2. Introduction to Earth Science Section 1  Earth science the scientific study of Earth and the universe around it  Scientific study of Earth began thousands of years ago with careful observations.  For many centuries, scientific discoveries were limited to observations of phenomena that could be seen with the unaided eye.  Earth science assumes that the causes of natural events, or phenomena, can be discovered through observation and experimentation. The Scientific Study of Earth

3. Introduction to Earth Science Section 1  Scientists have used technology and hard work to build an immense body of knowledge about Earth.  Most Earth scientists specialize in one of four major areas of study: the solid Earth (geology), the oceans (oceanography), the atmosphere (meteorology), and the universe beyond Earth (astronomy). Branches of Earth Science

4. Introduction to Earth Science Section 1 Geology  geology the scientific study of the origin, history, and structure of Earth and the processes that shape Earth  Geology includes many specialized fields of study, such as the study of earthquakes or volcanoes, exploration for natural resources such as coal and oil, and the study of Earth’s history through the study of rocks and fossils. Branches of Earth Science, continued

5. Introduction to Earth Science Section 1 Oceanography  oceanography the scientific study of the ocean, including the properties and movement of ocean water, the characteristics of the ocean floor, and the organisms that live in the ocean  Like geology, oceanography includes specialized fields. Some oceanographers study ocean water. Others study waves, tides, and ocean currents. Still others study the ocean floor or the organisms that live in the oceans. Branches of Earth Science, continued

6. Introduction to Earth Science Section 1 Meteorology  meteorology the scientific study of Earth’s atmosphere, especially in relation to weather and climate  Using satellites, radar, and other technologies, meteorologists study the atmospheric conditions that produce weather. They may use this information to prepare weather forecasts.  Some meteorologists study climate, the patterns of weather that occur over long periods of time. Branches of Earth Science, continued

7. Introduction to Earth Science Section 1 Astronomy  astronomy the scientific study of the universe  Astronomy is one of the oldest branches of Earth science.  Modern astronomers use Earth-based and space-based telescopes, as well as other instruments, to study the sun, the moon, the planets, and the universe. Branches of Earth Science, continued

8. Introduction to Earth Science Section 1 Reading Check What information is used for weather maps? Meteorologists use information gathered by satellites, radar, and other technologies on factors such as wind speed, temperature, and rainfall to create weather maps. Branches of Earth Science, continued

9. Introduction to Earth Science Section 1 Environmental Science and Earth Science  Environmental science is a relatively new field of Earth science that involves the study of the ways in which humans interact with their environment.  Many fields of study contribute to environmental science, fields such as Earth science, biology, and the social sciences.  The goal of environmental science is to understand and solve problems that result from how we use natural resources and how our actions affect the environment. Branches of Earth Science, continued

10. Introduction to Earth Science Section 1  Natural forces not only shape Earth but also affect life on Earth. By understanding how natural forces shape our environment, Earth scientists can better predict potential disasters and help save lives and property.  The work of Earth scientists helps us understand our place in the universe.  The study of Earth science can help people gain access to Earth’s resources, and Earth scientists also strive to help people use those resources wisely. The Importance of Earth Science

11. Introduction to Earth Science Section 2 SECTION 2: SCIENCE AS A PROCESS Preview  Key Ideas Key Ideas  Behavior of Natural Systems Behavior of Natural Systems  Scientific Methods Scientific Methods  Scientific Measurements and Analysis Scientific Measurements and Analysis  Models Models  Acceptance of Scientific Ideas Acceptance of Scientific Ideas  Science and Society Science and Society  Maps in Action Maps in Action

12. Introduction to Earth Science Section 2 BEHAVIOR OF NATURAL SYSTEMS  The goal of science is to explain natural phenomena.  Scientists ask questions about natural events and then work to answer those questions through experiments and examination.

13. Introduction to Earth Science Section 2 BEHAVIOR OF NATURAL SYSTEMS, CONTINUED  Scientists start with the assumption that nature is understandable.  Scientists also expect that similar forces in a similar situation will cause similar results.  Scientists also expect that nature is predictable, which means that the future behavior of natural forces can be anticipated.

14. Introduction to Earth Science Section 2 SCIENTIFIC METHODS, CONTINUED Over time, the scientific community has developed organized and logical approaches to scientific research. These approaches are known as scientific methods. The diagram below shows a basic flowchart of scientific methods.

15. Introduction to Earth Science Section 2 SCIENTIFIC METHODS, CONTINUED Ask a Question  observation the process of obtaining information by using the senses; the information obtained by using the senses  Scientific investigations start with observations which lead to questions.  Simple questions have fueled years of scientific research and have been investigated through scientific methods.

16. Introduction to Earth Science Section 2 SCIENTIFIC METHODS, CONTINUED Form a Hypothesis  hypothesis a testable idea or explanation that leads to scientific investigation  Once a question has been a scientist may propose a tentative answer, which is also known as a hypothesis.  Most hypotheses are based on known facts about similar events – what typically happens.

17. Introduction to Earth Science Section 2 SCIENTIFIC METHODS, CONTINUED Reading Check  Name two ways scientific methods depend on careful observations.  Observations may lead to interesting scientific questions and may help scientists formulate reasonable and testable hypotheses.

18. Introduction to Earth Science Section 2 SCIENTIFIC METHODS, CONTINUED Test the Hypothesis  After a hypothesis is proposed, it is commonly tested by performing experiments. An experiment is a procedure that is carried out according to certain guidelines.  independent variable in an experiment, the factor that is deliberately manipulated – X axis on a graph  dependent variable in an experiment, the factor that changes as a result of one or more other factors (the independent variables) – Y axis on a graph

19. Introduction to Earth Science Section 2 SCIENTIFIC METHODS, CONTINUED Draw Conclusions  After many experiments and observations, a scientist may reach conclusions about his or her hypothesis.  If the hypothesis fits the known facts, it may be accepted as true.  If the results differ the hypothesis is changed or discarded.

20. Introduction to Earth Science Section 2 SCIENTIFIC MEASUREMENTS AND ANALYSIS  Measurement is the comparison of some aspect of an object or event with a standard unit.  Scientists around the world can compare and analyze each other’s measurements because scientists use a common system of measurements called the International System of Units, or SI.

21. Introduction to Earth Science Section 2 SCIENTIFIC MEASUREMENTS AND ANALYSIS, CONTINUED Accuracy and Precision Accuracy refers to how close a measurement is to the true value of the thing being measured – hitting the bulls eye on a dart board. Precision is the exactness of the measurement – close together.

22. Introduction to Earth Science Section 2 SCIENTIFIC MEASUREMENTS AND ANALYSIS, CONTINUED Error  Error is an expression of the amount of imprecision or variation in a set of measurements.  Error is commonly expressed as percentage error.

23. Introduction to Earth Science Section 2 SCIENTIFIC MEASUREMENTS AND ANALYSIS, CONTINUED Observations and Models  In Earth science, using controlled experiments to test hypotheses is often impossible.  When experiments are impossible, scientists make additional observations to gather evidence.  The hypothesis is then tested by examining how well the hypothesis fits or explains all of the known evidence.

24. Introduction to Earth Science Section 2 SCIENTIFIC MEASUREMENTS AND ANALYSIS, CONTINUED Observations and Models, continued  Scientists also use models to simulate conditions in the natural world.  A model is a description, representation, or imitation of an object, system, process, or concept.  Scientists use several types of models, including physical models, graphical models, conceptual models, mathematical models, and computer models.

25. Introduction to Earth Science Section 2 SCIENTIFIC MEASUREMENTS AND ANALYSIS, CONTINUED Reading Check Name three types of models. Answers should include three of the following types of models: physical models, graphic models, conceptual models, computer models, and mathematical models.

26. Introduction to Earth Science Section 2 ACCEPTANCE OF SCIENTIFIC IDEAS  Scientific understanding moves forward through the work of many scientists, who build on the research of the generations of scientists before them.  When scientists reach a conclusion, they introduce their findings to the scientific community. Publication of Results and Conclusions  Scientists commonly present the results of their work in scientific journals or at professional meetings.  Results published in journals are usually written in a standard scientific format.

27. Introduction to Earth Science Section 2 ACCEPTANCE OF SCIENTIFIC IDEAS, CONTINUED Reading Check Name two places scientists present the results of their work. Scientists present the results of their work at professional meetings and in scientific journals.

28. Introduction to Earth Science Section 2 ACCEPTANCE OF SCIENTIFIC IDEAS, CONTINUED Peer Review  Scientists follow an ethical code that states that only valid experimental results should be published.  To reduce bias, scientists submit their ideas to other scientists for peer review.

29. Introduction to Earth Science Section 2 ACCEPTANCE OF SCIENTIFIC IDEAS, CONTINUED Formulating a Theory  When an idea has undergone much testing and reaches general acceptance, that idea may help form a theory.  Scientific theory the explanation for some phenomenon that is based on observation, experimentation, and reasoning; that is supported by a large quantity of evidence; and that does not conflict with any existing experimental results or observations  A scientific law is a general statement that describes how the natural world behaves under certain conditions and for which no exceptions have been found.  Theories and scientific laws can be changed if conflicting information is discovered in the future.