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EARTH SCIENCE: PROLOGUE. TOPIC I - OBSERVING AND MEASURING THE ENVIRONMENT TOPIC II - THE CHANGING ENVIRONMENT. PROLOGUE ... THE INTRODUCTION TO EARTH SCIENCE!. OBSERVING MEASURING DESCRIBING CHANGES. SO HOW DO SCIENTISTS STUDY EARTH ?. MAKE OBSERVATIONS
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EARTH SCIENCE: PROLOGUE TOPIC I - OBSERVING AND MEASURING THE ENVIRONMENT TOPIC II - THE CHANGING ENVIRONMENT
PROLOGUE ... THE INTRODUCTION TO EARTH SCIENCE! • OBSERVING • MEASURING • DESCRIBING CHANGES
SO HOWDO SCIENTISTS STUDY EARTH? • MAKE OBSERVATIONS • USE INSTRUMENTS • MAKE INFERENCES
AN INTERPRETATION OF OBSERVATIONS MAKING A GUESS BASED ON INFORMATION YOU HAVE EXAMPLE: I SEE YOU ARE SLEEPING IN MY CLASS…YOU DID NOT SLEEP WELL LAST NIGHT ! IS THAT TRUE? WHAT’S AN INFERENCE?
TO ORGANIZE OBSERVATIONS AND INFORMATION BASED ON OBSERVABLE PROPERTIES AND COMMON CHARACTERISTICS EXAMPLES: CLOUDS MINERALS ROCKS HURRICANES TORNADOES RIVERS SCIENTISTS USE CLASSIFICATION SYSTEMS
ALWAYS HAVE A NUMBER VALUE AND A UNIT 365 DAYS 37 KM 799 GRAMS 15 ° TYPICAL EARTH SCIENCE MEASUREMENTS TIME LENGTH MASS TEMPERATURE OBSERVATIONS INVOLVE MEASUREMENTS
SOME MEASUREMENTS ARE DERIVED • USE MATH OPERATIONS TO DERIVE THE MEASUREMENT • VOLUME = L x W x H • SPEED = LENGTH ÷ TIME (miles per hour)
MOST MEASUREMENTS HAVE SOME DEGREE OF ERROR • CALLED PERCENT ERROR PERCENT DEVIATION • SIMILAR TO A TEST GRADE • HOW MANY WRONG (ERROR) OUT OF THE NUMBER OF POSSIBLE RIGHT • ALWAYS EXPRESSED AS %
PERCENT ERROR • MEASURE THE MASS OF A ROCK • YOU SAY IT’S 40 g • ACTUALLY IT’S 50g DIFFERENCE BETWEEN THEM ——————————————— x 100 ACTUAL MEASUREMENT
GRAPHING HELPS PRESENT INFORMATION • SEE RELATIONSHIPS AND CHANGES • COMPARE VARIABLES • DEPENDENT • INDEPENDENT
DENSITY: A DERIVED MEASUREMENT • THE CONCENTRATION OF MATTER • ALL SAMPLES OF THE SAME MATERIAL HAVE THE SAME DENSITY … REGARDLESS OF SIZE OR SHAPE
DENSITY = MASS ÷ VOLUME • MEASURE MASS • DETERMINE VOLUME • DO THE MATH ! ! • INCLUDE UNITS • GRAMS/CM³
HEAT AND PRESSURE CHANGE DENSITY • ADDING HEAT CAUSES MOLECULES TO EXPAND . . . THAT’S WHY WARM AIR RISES ! • PRESSURE INCREASES DENSITY…MOLECULES ARE PRESSED TOGETHER! • HEAT AND PRESSURE AFFECT THE STATE OF MATTER
SUBSTANCES ARE MOST DENSE AS SOLIDS • WATER IS THE EXCEPTION! • IT’S MOST DENSE AS A LIQUID AT 4° C • SOLID WATER FLOATS IN LIQUID WATER. . . IS THAT WEIRD?
TOPIC II – THE CHANGING ENVIRONMENT • CHANGE HAPPENS ALL THE TIME! • DESCRIBED IN TERMS OF TIME AND SPACE . . . WHEN AND WHERE! • EXAMPLES • WEATHER • RIVERS • GLACIERS • MOUNTAINS • OCEANS
HOW MANY DEGREES THE TEMPERATURE DROPPED IN AN HOUR HOW MANY INCHES OF SNOW FELL DURING THE NIGHT HOW MUCH EROSION HAPPENED IN ONE YEAR EQUATION TO FIND THE RATE OF CHANGE: CHANGE IN FIELD VALUE ———————————— CHANGE IN TIME “FIELD VALUE” IS THE THING THAT IS CHANGING … TEMPERATURE, SNOW, EROSION . . . RATE OF CHANGE . . . CHANGE IN RELATION TO TIME
SOME CHANGES ARE CYCLIC • ORDERLY CHANGES WITH A PATTERN • SUNRISE/SUNSET • SEASONS • OCEAN TIDES • MOON PHASES
ALL CHANGES TAKE ENERGY! • ENERGY FLOWS FROM ONE PART OF THE ENVIRONMENT TO ANOTHER • INTERFACE - A BOUNDARY BETWEEN MATERIALS… WHERE ENERGY IS EXCHANGED
WHERE IS THE INTERFACE?WHAT’S THE SOURCE OF ENERGY?ARE THE WAVES CYCLIC?
OBSERVATIONS INFERENCE CLASSIFICATION PERCENT ERROR INDEPENDENT VARIABLE DEPENDENT VARIABLE DENSITY RATE OF CHANGE CYCLIC CHANGE ENERGY INTERFACE LET’S REVIEW ... 10 BASIC TERMS