Wet places, dry places

When we talk about the weather, we talk about the temperature - that is, how cold or hot it is.We also talk about rain. Some places have rain almost every day. Other places do not get a single drop for several years. Cold places get snow instead of rain. The kind of weather a place gets over a long period of time is called its climate.
Our world can be divided into regions which share the same kind of climate. For example, regions near the Equator are hot, but they usually get plenty of rain. But near the Tropics of Cancer and Capricorn, There are hot deserts which get hardly any rain. Between these deserts and the icy polar regions are the temperate zones. Some temperate zones are rainy. Others are dry.

Hot places, cold places

The Sun gives our world light and heat. The heat is strongest around the middle of the world. This means that lands near the Equator and the two Tropics are hot most of the time.

Where the Sun's heat is much less strong near the Poles it is cold for most of the year. This is partly because the Sun's rays are spread over a much larger area.

Places lying between the poles and Tropics have much more changeable weather. They usually have four seasons - winter, spring, summer and autumn. Summers are warm, but nit as hot places near the Equator. Winter are cold, but not as icy as near the Poles. These large areas, called zones, are known as 'temperate zones'. Temperate means neither very hot very cold.

Not all places in the world fit into this pattern of hot and cold. You can sometimes find snow on the Equator! Very high places, like  mountain peaks, are much colder than low places. For this reason, high mountain can be cold and snow - capped even when they are in the hottest parts of the world.

The world's axis is an imaginary line that runs right through the center of the Earth from the North Pole to the South Pole. This imaginary line isn't upright like a flagpole, it is tilted because the would leans to one side.

As the Earth travels around the Sun, first the top half and then the bottom half of the world leans towards the Sun.

When the top half leans towards the Sun, it gets more heat then the bottom half. This means that when it is the summer season in a country like Canada, in the top half of the world, it is winter in New Zealand in the bottom half.

Ocean bumps and dips

The land isn't under the sea!
From the edge of the shore, the continents slope down to the lowest parts of the oceans. If we could pumps out all the seawater, we would find some large flat plains on the ocean floor, but we would also see bumps and dips - just as on land.
Long mountain ranges, bigger than any on land, rise from the ocean floor. Some of these are so high that their tops rise above the waves. The tops from island.
The deepest dips in the oceans are long valleys called trenches.

Our watery world

On the world map, you can see that water covers more than two thirds of our world. Imagine you were an alien in a spaceship! When you first caught sight of Earth you would probably name it 'Watery Plant'.
The world's water is divided into large areas called oceans. The biggest ocean is the Pacific Ocean. It separates North and South America from Asia and Australia. It is so big that all continents could fit into it. The second biggest ocean is the Atlantic. The third largest ocean is called the Indian Ocean. The fourth ocean in size is the icy Arctic Ocean around the North Pole.
The water around the bottom of the world are sometimes called the Antarctic Ocean. But these waters are really the southern parts of the Pacific, Atlantic and Indian oceans.
The waters of the oceans mix together. They are all parts of one world oceans. You can see this on the map. The dividing lines, or borders, between oceans are shown in red. For example, the border between the Pacific and Atlantic oceans is an imaginary line running down from the tip of south America. Can you see the other oceans borders?
Oceans cover big areas. Each ocean contains smaller areas called seas. Seas are partly surrounded by land. Gulfs are large inlets of the oceans. Bays are smaller inlets. Straits are narrow strips of water. They link larger parts of the oceans.

Bumps and dips

The surface of the land is not flat all over. There are many parts that dip down and many that reach up high. Flat areas of land are called plains. The smaller bumps are hills and the larger ones are mountains. The dips are valleys.
Sometimes the valleys are filled with water. Large Stretches of water that gather in wide valleys are called lakes. Other valleys have rivers flowing through them, carrying water from the land to the sea.
Plains, mountains, lakes and rivers can be shown on maps. They are shown as simple drawing called symbols. The blue line on a map in this atlas, You will know that a river runs through that part of the land. Here are some of the symbols we use in this atlas.

The continents

Land covers just under a third of the surface of our world. The rest is water.This land is made up of seven main areas. Each of these areas is called a continent. Each continent also includes some island.
The largest of the seven continents is Asia. The second largest is Africa. North America comes third and South America fourth. Antarctica, the fifth largest continent, surrounds the south pole at the bottom of the world map. Europe is the sixth largest continent and Australia is the smallest.

Water surrounds some continens. Other are joined. The dividing line between two continents is called a border. For example, North America is separated from South America by a short land border. The border between Europe And Asia stretches many thousands of kilometers.
Look carefully at the world map and you will see that each continent has its own special shape. At first glance, you might think that South America and Africa look similar. Both are wide at the top and narrow at the bottom. But look again. You will see that South America tapers almost to a point, like a carrot. The bottom of Africa is much winder.