Welcome to Earth Science! Chapter 1: Introduction to Earth Science BIG Idea: Earth Scientists use specific methods to investigate Earth and beyond. I. What is Earth Science? the study of the Earth and the universe around it… the study of Earth systems and systems in space; including weather and climate systems, and the study of nonliving things such as rocks, oceans, and planets. A. The Scope of Earth Science: 1. Astronomy: the study of objects beyond Earth’s atmosphere. The oldest branch of Earth Science. 2. Meteorology: the study of Earth’s atmosphere. Weather Forecasters Tornado Chasers 3. Geology: the study of the origin, history, and structure of Earth. The study of SOLID earth. 4. Oceanography: the study of the life and properties of Earth’s oceans. JACQUES COUSTEAU How much of our Earth is covered by water? almost three-fourths! Of that water, how much is salt water? about 97% 5. Environmental Science: the study of the interactions of organisms and their surroundings. B. Earth’s Systems 1. Geosphere: the area from the surface of Earth down to its center. Three main parts: a) Crust b) Mantle c) Core Inner core Outer core 2. Atmosphere: the blanket of gases that surrounds our planet. 3. Hydrosphere: all the water on Earth. 4. Biosphere: all organisms on Earth and the environments in which they live. II. Methods of Scientists Scientific Methods: series of organized problem-solving procedures that help scientists conduct experiments. There are five (5) steps to the SCIENTIFIC METHOD: 1. State the Problem, or…Ask a Question? Observation: use of senses to gather information about the world. What is the difference between an OBSERVATION and an INFERENCE? Observation: receiving knowledge of the outside world through our senses, or recording information using scientific tools and instruments. Inference: reasoning involved in drawing a conclusion or making a logical judgment on the basis of circumstantial evidence and prior conclusions rather than on the basis of direct observation. How will YOU remember the difference? 2. Gather Information To investigate a problem, one must gather information… Measurement: comparing some aspect of an object with a standard unit. meters, inches, miles grams, ounces, pounds 3. Form a Hypothesis Hypothesis: a possible solution or answer to your problem or question; MUST be testable! Can be proven wrong. 4. Test the Hypothesis Experimentation: procedure carried out to prove or disprove a hypothesis. (a) Independent Variable: variable that you, the experimenter, changes (the manipulated variable) (b) Dependent Variable: variable that is affected by changes in the independent variable; factor being measured (the responding variable) (c) Constants: things that never change during the experiment (d) Control: duplicate setup of the experiment with everything the same except the variable you are testing. 5. State a Conclusion After many experiments and observations, the hypothesis is either proved or disproved… Scientific Method Scenario: David read that Fox brake pads and Best brake pads were the best on the market. He always used NAPA pads and believed they performed the best. He decided to test all three pads and determine which was the best. David used the same car for each set of pads. He drove 25 mph and applied the brakes at the same point on the track. David then measured how many feet the car took to stop after the brakes were applied. 1. The hypothesis: ____________________________________ 2. The effects of the ________________(independent variable) on the __________________________________ (dependent variable). 3. List three constants: •______________________________________ •______________________________________ •______________________________________ Scientific LAW: a statement of fact that is believed to be always true - STATES and describes behavior of natural phenomenon, does NOT explain them - a ‘rule of nature’ - observable but not explainable - EXAMPLES of Scientific Laws: Law of Inertia Kepler’s Laws of Planetary Motion Newton’s Universal Law of Gravitation Scientific THEORY: an explanation based on many observations during repeated investigations - the best available explanation of a phenomenon - a hypothesis that is supported by the experiments - may change with the discovery of new data - EXAMPLES of Scientific Theories: Heliocentric Theory Theory of Evolution Meteorite Impact Theory Big Bang Theory "Scientific laws are the evidence used to support a conclusion. Scientific theories are our best attempts at explaining the behavior of the world, in ways that can be tested by further experiment. The facts (the scientific laws) must convince us that our theory is a good explanation for what happened." Meteorite Impact Theory Explains the extinction of the dinosaurs Meteorite hit the earth 65 million years ago The impact created so much dust it blocked out the sun No sun, no plants…almost everything died Proof: Computer models Deformed quartz Iridium around the impact site III. Communication in Science lab reports graphs models