Earth is unique among the nine planets that circle the sun.It is the only one planet that can support life,because it has enough oxygen in its atmosphere and plentiful water.In fact, seen from space,Earth looks almost entirely blue.This is because about 70% of its surface is under water, submerged beneath four huge oceans: the Pacific, Atlantic, Indian and Arctic oceans.Land makes up about 30% of the Earth's surface.It is divided into seven landmasses of varying shapes and sizes called continents.These are, from largest to smallest :Asia, Africa, North America, South America, Antartica, Europe and Australia.
· Wet Earth : Tropical rainforests grow in areas close to the Equator, where it is wet and warm all year round. Although they cover just 7% of the Earth's land, these thick, damp forests form the richest ecosystems on the planet.More plant and animal species are found here than anywhere else on Earth.
· Dry Earth : Deserts are among the most inhospitable places on the planet. Some deserts are scorching hot, others are freezing cold, but they have one thing in common - they are all dry. Very few plant and animal species can survive in these harsh conditions. The world's coldest and driest continent, Antartica, is a cold desert.
· Watery world : The Earth's oceans and seas cover more than 367 million sq km - that is twice the surface of Mars and nine times the surface of the moon. Beneath the ocean waves lies the biggest and most unexplored landscape on Earth.Here are coral reefs, enormous, open plains, deep canyons, and the biggest mountain range on Earth - the Mid-Atlantic Ridge-which stretches almost from pole to pole. · Oceans
· Indian ocean : The Indian Ocean covers about 20% of the world's surface. Ocean swells, starting deep in the Southern Ocean, often cause flooding in Sri Lanka and the Maldives.
· Pacific ocean : The Pacific is the largest and deepest ocean in the world. It contains an arc of volcanic islands, including Japan, Indonesia and New Guinea, known as the 'Ring of Fire'.
· Atlantic ocean : The Atlantic Ocean was formed about 180 million years ago. The land which now forms Europe and Africa pulled apart from the Americas to create an ocean 3,000 km wide.
There are nearly 190 countries worldwide. Russia is the largest country, while Vatican City in Rome is the smallest--it's less than half a mile wide! But there are also dozens of territories, colonies, and dependencies. These are areas that are under the control of larger countries. For instance, Samoa, a group of islands in the Pacific Ocean, is under the control of the United States. And there are many territories that want to be officially recognized as independent countries. So the number changes from year to year. THE ARCTIC
Arctic Ocean is encircled by the most northerly parts of Europe, North America and Asia.Very few people live in the often freezing conditions.They are the Sami of northern Scandinavia,the Siberian Yugyt and Nenet people and the Canadian Inuit.The Arctic Ocean is the smallest ocean in the world.When the ice breaks up, it forms enormous floating ice-masses called icebergs.There are many thousands of islands in the Arctic for example,Baffin Island and Victoria Island, are almost entirely surrounded by pack-ice.
Africa is the second largest continent in the world. According to the human evolution theory, scientists declared Africa as the place where humans first evolved. Today, there are 53 seperate countries in Africa, and its people speak a rich variety of languages. The world's highest temperatures have been recorded in Africa's deserts.Fifteen countries are land-locked,which means that they do not access to the sea. Cairo in Egypt is the continent's largest city. The World's largest continent, ASIA
Asia, the world's largest continent has the greatest range of physical extremes. Some of the highest, lowest, and coldest places on Earth are found in Asia : Most in the Himalayas is thehe west is the lowest, and the frozen wastes of northern Siberia are among the coldest. More people live in Asia than on any other continent - 1.2 billion of them in China, and 940 million in India.The Himalayas are a relatively young mountain range, and are still being uplifted. They began to form when India collided with Asia, crumpling the land and forcing it up into high peaks.India is the world's largest democracy, while China is a communist power with restricted access to the rest of the world. In the far north of Asia, the land is permanently frozen - this is known as permafrost. USA
USA - United States of America is one of the most popular countries in the world.Everybody in this world will dream of America.Now-a-days youth of all over the world rush towards America for studying or working.We all definitely wish to enjoy the fun world of Disneyland and the great Niagara falls, Liberty statue,State Empire building and so many things to be enjoyed by people all over the world. Antarctica
Antarctica ia the world's most southernly continent. It is also the world's coldest continent.Even in the summer the temperature is rarely above freezing and the sea-ice only partly melts; in winter,temprratures plummet to -80degree Centigrade. The only people who live in Antarctica are teams of scientists who study the wildlife and monitor the ice for changes in the Earth's atmosphere.