1. Honors Earth / Environmental Science Ms. Reathaford

2. The Nature of science
Chapter 1

3. Science
Science is the process of observing and studying things in our world.
Science can be applied to almost anything and is divided into four general areas:
1. Chemistry
2. Physics
3. Life Science (Biology, Anatomy, etc)
4. Earth Science
* Note that you MUST take 3 of these to graduate HS! *

4. Earth Science
Earth Science is the study of Earth and space. Within Earth Science, there are four major divisions:
1. Astronomy
2. Meteorology
3. Geology
4. Oceanography

5. Environmental Science
The systematic study of our environment and our proper place in it
Draws on many disciplines, skills and interests
Integrates natural sciences and social sciences
Integrates humanities in a broad, holistic study of the world around us
Persistent challenges to face, most of which we have created
Pollution Population Growth
Climate Change Biodiversity Loss
Improvement in many areas that benefit our planet
Education Health Care
Water Quality Energy alternatives

6. Origin of the Earth
Most scientists believe that Earth and the other planets formed at essentially the same time from the same primordial material as the Sun.
This nebular hypothesis indicates that the solar system evolved from an enormous rotating cloud called a solar nebula that was composed mostly of hydrogen and helium. This nebula is believed to have begun contracting about 5 billion years ago, assuming a flat, disk shape with a proto-sun (pre-Sun) at the center.
From this point, the planets began to form from metallic and rocky clumps of substances, leading to a layered structure.

7. Formation of Earth’s Layered Structure
As the Earth formed, the decay of radioactive elements and heat from high-velocity impacts caused the temperature to increase throughout the “planet”
Iron and nickel began to melt and sink toward the center
Lighter rocky components floated outward, toward the surface
Layers were formed according to density

8. The Earth’s Crust
The crust is the outermost, and best-known, layer of the Earth.
Characteristics:
Coolest layer of Earth
Approximately 30 miles thick
Thin, rigid layer floating on the mantle
Composed of three major rocks groups
Composition includes primary elements of Si, O, Fe, Al, Ca, and Na, with most prevalent being the rock forming group Silicates (Si, O)
Two types of crust:
Continental (Primarily Granite)
Oceanic (Primarily Basalt)

9. Mohorovicic Discontinuity (Moho)
Between the between the crust and mantle there is an actual boundary, called the Mohorovicic (MOE-hoe- roe-VIT-jich) Discontinuity. (Moho Layer)
The depth varies:
About 3 miles (5 kilometers) beneath the ocean floor
About 25 miles (40 kilometers) beneath the continents

10. Lithosphere
The rigid layer of the Earth’s surface - composed of the crust and upper most part of the mantle.
Characteristics:
Broken into a number of plates
Floats on a denser, more plastic like layer of upper mantle
Distinguished from asthenosphere based on how easily it flows

11. Mantle
The mantle is the thick layer of hot, solid rock located between the Earth’s crust and the molten iron core.
The mantle makes up the bulk of the Earth, accounting for 2/3 of the planet's mass, starting about 30km down and is about 2,900km thick.
The Earth’s mantle can be divided into two parts:
Asthenosphere (upper mantle)
Mesosphere (lower mantle)

12. Asthenosphere The denser, more plastic layer of the upper mantle.
Characteristics:
Partially molten
Deformable region
Temperature and pressure lead to partial melting of rock and loss of strength of layer
Low seismic activity within this region
Behaves like hot asphalt

13. Mesosphere
Beneath the lithosphere and asthenosphere, classified as the lower mantle.
Characteristics:
Increase in pressure (due to increasing depth)
Material is all solid but will convect slowly due to temperature gradients and density differences

14. Core
The core is the deepest and hottest layer of the Earth, made almost entirely of metals. Like the mantle, the core is also divided into two parts:
Outer Core
Approximately 1,430 miles thick
Hot Liquid (estimated between 7,000-9,000 degrees Fahrenheit)
Composed primarily of iron and Nickel
Inner Core
Approximately 750 miles thick
Despite the intensive heat (9,000-13,000 degrees Fahrenheit) it is solid due to the intense pressure from the rest of the planet
Composed primarily of Iron

15. “A Slice of Earth” Diagram Activity
Structure of the Earth
“A Slice of Earth” Diagram Activity

16. The Earth’s Systems
Within the Earth, scientists have developed four main systems. (Some argue 5)
Each system is unique, but interacts with the others.
None of the systems are independent of the others, nor of the global system of the Earth itself.

17. The Geosphere The Crust: The Mantle: The Core:
The Geosphere is based on the composition (chemistry) differences of:
Crust
Mantle
Core
Divisions of the outer portion are based on how the materials behave.
The Crust:
1. Continental – made primarily of granite
2. Oceanic – made primarily of basalt
The Mantle:
Composed primarily of peridotite
Parts of the mantle are solid, but some act more as a liquid
The Core:
Composed primarily of iron and nickel
Outer Core is liquid
Inner Core is solid

18. The Hydrosphere
The hydrosphere covers approximately 71% of the Earth’s surface, with the most prominent feature being the ocean.
The hydrosphere, ultimately, is comprised of all of the water on Earth.
Oceans and seas
Lakes, rivers, and ponds
Glaciers and ice caps
Groundwater
Water in the atmosphere
Hydrosphere composition:
97% salt water
3% fresh water
About ¾ of the freshwater is contained in glaciers and icebergs

19. The Cryosphere Sometimes considered part of the Hydrosphere
Contains all of the water that is in the form of ice
Ice caps
Snowfields
Glaciers
Ice sheets
Sea ice
Frozen ground (permafrost)
99% of Earth’s freshwater is contained in the Greenland and Antarctic ice sheets

20. The Atmosphere Blanket of gases that surrounds our planet
Necessary for respiration of most living things
Protects inhabitants from radiation of Sun
Maintains suitable temperature for life
Current Composition:
78% Nitrogen
21% Oxygen
1% Other gases
(water vapor, argon, carbon dioxide, trace gases)

21. The Biosphere
Includes all organisms on Earth as well as the environments in which they live.
The majority of the Earth’s organisms live within a few meters of the Earth’s surface; however, some live deep beneath the ocean surface and some live high atop the Earth’s mountains.
The Earth’s biosphere is unique in that scientists have yet to confirm evidence of life on other planets or elsewhere in the galaxy.
Extreme influences on other three spheres

22. A Complete System
The Earth is a dynamic body with many separate but highly interacting parts, or spheres.
Earth system science is the study of the Earth as a system composed of numerous parts, or subsystems.
System - any size group of interacting parts that form a complex whole
Two Types:
Closed systems – self-contained (e.g. an automobile cooling system)
Open systems – systems where both energy and matter flow into and out of the system (e.g. a river system)

23. The Earth as a System An endless array of subsystems:
Hydrological Cycle
Carbon Cycle
Nitrogen Cycle
Sources of energy:
The Sun
Drives external processes
Weather and climate
Ocean circulation
Erosional processes
The Earth's interior
Drives internal processes
Volcanoes
Earthquakes
Mountains

24. The Nature of Scientific Inquiry
All science is based on the assumption that the natural world behaves in a consistent and predictable manner.
News/media and many people in "authority" misunderstand the nature of scientific inquiry. For instance, they often indicate through news media that "It's only a theory ", insinuating that there is no proof, experiments, or observations behind the concept.

25. Hypotheses and Theories
Hypothesis
THEORIES
A tentative (untested) explanation of a natural phenomena
A hypothesis must be testable
A hypothesis may change or be modified with the discovery of new data
A basic principle describing the behavior of a natural phenomena
Well tested
Can be thought of as a “rule,” although the cause may be unknown.
Events are observed to be the same every time

26. Scientific Law
LAWS
Describes the behavior of natural phenomena (rule of nature such as the Law of Gravity.)
An explanation based on many observations during repeated experiments.
Valid only if it is consistent with every other experiment that is done on it.
May change or be modified with the discovery of new data.

27. Methods of Scientists Scientific Method Determine the problem
Make a Hypothesis
Experiment
Independent Variable
Dependent Variable
Constant
Control
Collect Data
Analyze the Results
Draw Conclusions
Repeat

28. What is the Scientific Method?
A procedure used to scientists to test hypothesis by making predictions about the outcome of the experiment BEFORE it is performed is referred to as the scientific method.
Experiment Factors:
Independent Variable: factor manipulated BY the experimenter
Dependent Variable: Changes due to the individual experiment
Constant: Variables do not change
Control: “Base Group” for the experiment
Data:
Quantitative: can be ordered (weight, temperature)
Qualitative: different in types – NOT ordered (gender, species)

29. Science and Technology
The application of scientific knowledge and discoveries.
Transferrable – can be applied to new situations.
Can be good OR bad…
Good – computers, health care
Bad – air pollution, deforestation, eliminates jobs

30. Safety in the Science Lab
1. Understand all safety symbols before beginning
2. Wear safety goggles when using chemicals
3. Tie back long hair / loose clothing
4. Always slant tubes AWAY from yourself and others
5. Never Eat / Drink in the lab. Use only laboratory glassware for experiments.
6. Never inhale chemicals or taste substances
7. Know what to do in case of a fire!
8. Report any spills, accidents or injuries to your teacher immediately
9. Clean up your space! (Dispose properly of chemicals as directed by your teacher.)
10. Always wash your hands, thoroughly, with soap and water after working in the lab

31. Measurement
Using measurements is common when conducting science experiments.
A measurement includes using both a number that identifies how many units there are and a unit of measure.
Most scientific studies and experiments use a standard system of units called Le Systeme International d’Unites (SI).
SI is the modern version of the metric system
Based on a decimal system that uses the number 10 as the base unit

32. Measurement Conversions
Prefix
Symbol
Meaning
kilo k
one thousand
hecto h
one hundred
deka da
ten --
(B)… m, L, g
BASE UNIT
deci d
one tenth
centi c
one hundredth
milli m
one thousandth

33. Length The standard SI Unit to measure length is the meter (m)
A meter is divided into 100 equal parts, called a centimeter (cm)
A centimeter is divided into 1000 equal parts, called a millimeter (mm)
What does this all mean?
1m = 100cm = 1000 mm

34. Weight and Mass WEIGHT MASS
The measure of the gravitational force on an object.
Varies with location, based on gravitational force (ie… a person on the moon)
Measured with some type of scale
The amount of matter in an object, dependent upon the number of atoms that make up the object.
Mass does not change with an object’s position.
Measured with triple beam balance

35. Area and Volume Volume is the amount of space occupied by an object.
Area is the amount of surface included within a set of boundaries.
Area is expressed in square units of length, such as m2 or cm2
Area is determined by multiplying length x width (l x w)
Volume is the amount of space occupied by an object.
m3 for a solid object
mL or L for fluid objects
1mL = 1 cc = 1cm3

36. Density
Density is the measure of the amount of matter that occupies a given space.
Density is expressed in grams per cubic centimeter (g/cm3), grams per milliliter (g/mL) or kilograms per cubic meter (kg/m3
Calculate density by dividing the mass of the matter by its volume (m/v)

37. Time & Temperature The interval between two events is time
Time is typically measured with a watch or clock
Most precise measure of time comes from an atomic clock
The SI unit for time is the second (s)
The measure of the average vibrations of the particles that make up a material is temperature
Particles that vibrate more quickly have a higher temperature
Particles that vibrate more slowly have a lower temperature
Measured in degrees, with a thermometer, and on a Celsius scale in Science

38. FORMULAS MEMORY RECALL Time = Mass (in kg) x 9.8m/s2
Area = length x width
Density = mass/volume
Volume = length x width x height
C to K = C
K to C = K –

39. Scientific Notation Expresses number as a multiple of ten
Example: = 1.25 x 1012
It is expressed as a number between 1 and 10, multiplied by a power of 10
The power is the number of places the decimal moves
A positive (+) moves the decimal to the left
A negative (-) moves the decimal to the right
Examples:
12500 = 1.25 x 104
= 1.25 x 10-4

40. Section 1.3 Communicating in Science
In Science, it is imperative to make all results available to others.
Why?
So results can be verified
So information can be used by others to conduct new experiments
How?
Lab Reports
Graphs
Models
Theories / Laws

41. Lab Reports
A lab report is when you record and analyze information you collected during your experiment.
Lab Reports are used to draw conclusions based on your data.

42. Models
A scientific model is an idea, a system, or a mathematical expression similar to the idea being explained.
Fairly accurate representation of your experiment.
Can change as data is collected.

43. Graphs Used to show comparisons between data within your experiment.
Each graph must have:
1. Title
2. Labeled Axis
3. Legend / Key
4. Must be completed in pencil

44. Steps to Making a Graph Determine the variables and label each axis
Dependent variable goes on the y-axis (vertical)
Independent variable goes on the x-axis (horizontal)
Determine the scale of the graph
Determine the number value for each square on the graph
Spread the graph out to take up the most equal amount of space
Plot the data points
Mark each data value with a dot
Draw the graph
Draw a line that best fits the data points
If there is more than one line on the graph, you must include a key identifying each line
Give the graph a descriptive title