Geographic grids are intersecting lines drawn on maps and globes. They are used to help locate and describe specific areas. Two sets of lines encircle the globe: lines of latitude and lines of longitude. The parallel lines of latitude are horizontal, running from east to west. The equator is the imaginary line from which latitude is measured; it is equidistant from the poles, dividing the globe into the northern and southern hemispheres. Unlike lines of latitude, which become progressively shorter as they near the poles, all of the lines of longitude are the same length. Longitudinal lines run from north to south, each individual vertical line intersecting both poles. The prime meridian is an arbitrarily selected line from which all of the others are measured. Any location on the globe can be described in terms its angular distance from the reference points of the equator (0° latitude) and the prime meridian (0° longitude).

Lesson 2 // Overview of Geography

Geography
Further Reference Microsoft Encarta 99 – Find: Lines of Latitude and Longitude

Objective:

The student will explore hemispheres, continents, parallels of latitude, and longitude, and time zones. The students will discuss and compare the time zones of the world.

Guided Practice:

1. Review the four hemispheres. Point out on a globe where each hemisphere is located.
2. Review line of latitude with the students. Using a globe point out the five primary lines of latitude.
3. Review lines of longitude. Point out the Prime Meridian and the International Date Line.

Independent Practice:

1. The student will answer the comprehensive questions that correspond to the reading.
2. The student will define lines of latitude and lines of longitude.
3. The student will mathematically determine the time difference between Nepal and the various time zone regions of the United States.

Optional Extensions:

1. Discuss the latitude and climate variations based on the latitude of any region on earth. Discuss the climate zones of any region based on its latitude.
2. Define the various climate zones.
3. Have the students create a map that outlines the world's climate zones using different colors for each zone.

Reading and Questions:

Hemispheres:

The earth is divided into four hemispheres. One way is at the equator, the imaginary line circling the earth halfway between the North Pole and the South Pole. This divides the earth in half from the top to bottom. The Northern Hemisphere is the northern half of the earth between the North Pole and the equator. The Southern Hemisphere is the southern half between the South Pole and the equator.

The other is from east to west. The Eastern Hemisphere is referred to as the Old World while the Western Hemisphere is considered the New World. The Eastern Hemisphere consists of four continents: Europe, Asia, Africa, and Australia. The Western Hemisphere has two continents: North America and South America. Antarctica is the seventh continent and it sits at the southern tip of both hemispheres around the South Pole.

Parallels of Latitude:

Parallel lines are two imaginary lines that never cross but stay the same distance apart. The parallels of latitude are imaginary lines on a globe that run east and west. As you know the equator is a line of latitude that divides the Northern Hemisphere from the Southern Hemisphere.

Longitude and Time:

Another set of imaginary lines on a globe is the lines of longitude. Lines of longitude run north and south on the globe and come together at the North and South Poles. Lines of longitude are referred to as meridians. The Prime Meridian is a longitudinal line that runs through Greenwich, England south through the western portion of Europe and Africa. Meridians measure the distance east and west of the Prime Meridian. It is at the Prime Meridian that the earth is divided into time zones by longitude lines. This allows us to know what time it is in other parts of the world. In the Western Hemisphere are the lines west of the Prime Meridian and in the Eastern Hemisphere are the lines that run east of the Prime Meridian.

If you look at 180 degrees longitude on a globe you will find a jagged line called the International Date Line. The beginning of a new day begins at midnight at the International Date Line. When it is midnight at the Prime Meridian it is 12:00 noon at the International Date Line. Refer to the world time zone map for a clear understanding of the world time zone differences.

1. How many hemispheres are there? Can you name them?
2. What is the name given to the imaginary line that encircles the earth?
3. How many continents are in the Eastern Hemisphere? Can you name them?
4. What are lines of longitude called?
5. What degrees longitude is the Prime Meridian?
6. If Mr.Cherilla is talking to you via a satellite phone from Kathmandu, Nepal at 10:00 p.m. on Friday, March 23, what time is it where you live?

Attach world maps that have:
hemispheres
latitude and longitude
time zones

AZ State Standard - 6SC-E6. Describe the distribution and circulation of the world’s water through ocean currents, glaciers, rivers, ground water and atmosphere.

AZ State Standard - SS3 E4 Demonstrate understanding of the characteristics, purposes and use of geographic tools to located and analyze information about people, places and environments, with emphasis on:

PO 1 ways to display geographic information and characteristics and purposes of maps, globes, aerial photographs, charts and satellite images.

PO 2 constructing and interpreting maps, charts and geographic databases using geographic information.

PO 3 drawing an accurate map after being given a description of a place.

PO 4 identifying and locating physical and cultural features in their own and nearby communities in the United States, and in regions of the world, and the relationship between them.

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