Name ______________________________________________
ES _____________
Unit Two
Measuring The Earth
I. The Earth’s Shape
A. Evidence the earth is round:
1. ______________________________________________________________________
______________________________________________________________________
2. ______________________________________________________________________
______________________________________________________________________
3. ______________________________________________________________________
______________________________________________________________________
The best evidence is:
________________________________________________________________.
They provide direct evidence of the earth’s shape.
B. The Precise Shape
Measurements of weight differ ___________________________________________________.
An object is found to ____________________________________________________________.
Weight is influenced by the pull of gravity on an object.
The closer an object is to _________________________________________________________
_______________________________________________________________________.
The poles must be closer to ____________________________________________ for an object
to weigh more.
Analysis of polar and equatorial diameters indicate that the earth ________________________
flattened at the poles and bulging at the equator.
The precise shape of the earth is an _____________________________________________.
This difference in diameter is ________________________________ when compared to
___________________________________________________________________________.
When drawn to scale, the earth must be represented as ______________________________.
The polar diameter is only 42 km smaller than the equatorial diameter.
The polar diameter is: 12,714 km
The equatorial diameter is: 12, 756 km
The height and depth of objects on the earth’s surface __________________________
_____________________________________________________________________________
When drawn to scale,
___________________________________________________________________!!
II. The Size of the Earth
Eratosthenes was a Greek mathematician. He was the first person to determine the
circumference of the earth. He did this 2,000 years ago! His method of determining the
circumference of a circle is still used today. Comparing the value he calculated to the known
circumference of the earth, Eratosthenes only had a 0.9% error! Wow!!!
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III. Parts of the Earth
A. The Lithosphere
The __________________________________________________ of the earth’s surface
Refers to ______________________________________________________________________
___________________________________________________________
The lithosphere continues _________________________________________________.
The uppermost layer is called the crust.
There are two types of crust:
______________________________________________________________________
***See ESRT page 10 for inferred properties of the earth’s interior***
B. Hydrosphere
This includes all of the __________________________________________________ the
earth.
~70% of the surface of the earth is covered by water
When compared to the size of the earth, ______________________________________
______________________________________________________________________
C. The Atmosphere
Includes all of the ________________________________________________________.
***See ESRT page 14 for selected properties of the earth’s atmosphere***
***See front page of your ESRT for average composition of the earth’s
lithosphere, hydrosphere and atmosphere.***
IV. Locating Positions on the Earth
Because the earth is a sphere, we use a coordinate system to precisely locate positions
on the earth. This system assigns two numbers to every point on the earth.
This system operates like a graph with horizontal and vertical values.
Like any graph, the horizontal value is stated first!
A. Latitude
Latitude is the ____________________________________________________________
The reference line of latitude is the __________________________. Its latitude is
__________________________________
Latitude is the __________________________________________________________
____________________________________________________________________________.
1. Measuring latitude in the Northern Hemisphere:
Latitude is
____________________________________________________________________
(________________________________________)
In Rochester, the altitude to Polaris is ~43º … what is our latitude? _________________
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B. Longitude
Longitude is the ____________________________________________________.
The reference line for longitude is the ________________________________________,
is _______________________ and runs from the _____________________________________
______________________________________.
The International Dateline is _______________________________________________
on the “opposite” side of the earth.
Longitude is the __________________________________________________________
______________________________________________________________________.
1. Measuring Longitude
Longitude is based upon the _______________________________________________
_____________________________________________________________________________.
Solar time is _____________________________________________________________.
The sun appears to travel through our sky in a _________________________________.
When the sun is at its ________________________________________________, the
time is said to be _____________________________________________________.
The sun appears to travel through our sky _____________________________________
This equals a rate of _______________________________________________________
When the solar time of two locations and the longitude of one location are known, the
new longitude can be determined.
If solar time is ____________________________ at the new location, you have traveled
_________________________.
If solar time is _______________________ at the new location, you have traveled
_________________________.
For example:
 It is 8:00 a.m. at one location and 12:00 p.m. at another.
 How many degrees of longitude separate the two locations?
_________________________
 Determine the time difference:
_________________________
 Set up the proportion:


Longitude = _______________________
The first location is ____________________ of the second because it is
____________________.
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You have traveled so that your solar time is 2:00 p.m. and your home solar time is 7:00 a.m.
How far have you traveled and in what direction?
 How many degrees of longitude separate the two locations?
_________________________
 Determine the time difference:
_________________________
 Set up the proportion:


Longitude = _______________________
The first location is ____________________ of the second because it is
____________________.
Degrees of latitude and longitude are divided into smaller components called minutes
__________________________________ is equal to ¼ of a degree
__________________________________ is equal to ½ of a degree
__________________________________ is equal to ¾ of a degree
Determine latitude and longitude
Polaris is 25º above the horizon. Local solar noon occurs at 11:00 GMT
________________________________________________
Polaris is now 20º above the horizon. Local solar noon now occurs at 9:00 GMT
________________________________________________
Latitude is written first, followed by the N/S direction
Longitude is next, followed by the E/W direction
Now you try!
Using your ESRT, find the latitude and longitude of:
 Rochester = _____________________
 Elmira = ________________________
 Watertown = ____________________________
V. Describing Earth’s Fields
A. Fields
A field is ________________________________________________________________
_____________________________________________________________________________
A field is the ___________________________________________________________________.
The field value is the ____________________________________________________________.
Examples of field values:
_________________________________
_________________________________
_________________________________
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_________________________________
B. Field Maps
Field maps are a visual _____________________________________________________
_____________________________________________________________________________.
They are created to provide a greater understanding of the data.
C. Isolines
Isolines are ______________________________________________________________
_____________________________________________________________________________.
Specific isolines and the field value they connect.
_________________ connect _______________________
_________________ connect _______________________
_________________ connect _______________________
_________________ connect _______________________
When drawing isolines:
Lines may ______________________________________
Lines may ______________________________________
Lines must _____________________________________
Lines must _________________________________________________________
Analyzing Field Maps
1. Slope/Gradient
We can visually estimate the amount that the field value changes by looking at the
spacing between the isolines.
If the lines are:
close together, _________________________________________________________
____________________________________________________________________________.
far apart, ______________________________________________________________
____________________________________________________________________________.
We can mathematically determine the amount of change by calculating the gradient
between two points on a field map.
 Gradient = _____________________________
2. Stream Flow
By analyzing the contour lines, we can determine the direction a stream flows.
Contour lines bend towards ________________________________________________
Therefore:
___________________________________________________
3. Depressions
Indicated by hachure marks on contour lines.
The first depression contour is ______________________________________________
_____________________________________________. The values continue downward by the
existing contour interval.
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4. Drawing a Profile
 ________________________________________________________________
 ________________________________________________________________
 ________________________________________________________________
 ________________________________________________________________
Now you try!
Use the 5 concentric circles after the notes on the following page
Label each line (create a contour interval)
Identify a line to profile
Draw your profile.
5. Estimating Elevation
When asked to approximate elevation,
 you must ________________________________________________________________
 The estimated value must be between them
a. Highest possible elevation
Last contour line is 700 m
If there was a next contour line, it would be 800 m
The highest possible elevation of an indicated point is _________________________
b. Lowest possible elevation
Last contour line is 100 m
Next contour line would be 80 m
Lowest possible elevation of an indicated point would be _______________________
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