INTRODUCTION TO GEOGRAPHY

The term "geography" comes from the ancient Greeks, who needed a word to describe the writings and maps that were helping them make sense of the world in which they lived. It is a combination of two Greek words: "geo" and "graphia". In Greek, "geo" means “Earth” and "graphia" means “to write, draw or describe”.

These two words together form geography, which means to draw, write about or describe the Earth. These meanings led to the development of the early definition of geography which referred to description of the Earth by words, maps and statistics and included both the physical Earth and everything found on it such as plants, animals and people. Therefore, geography is the study of the distribution and interrelationship of phenomena in relation to the Earth’s surface. Alternatively, geography can be described as the study of the Earth and its environment.

Geographers explore both the physical properties of Earth’s surface and the human societies spread across it. They also examine how human culture interacts with the natural environment and the way locations and places can have an impact on people. Geography seeks to understand where things are found, why they are there, and how they develop and change over time.

There are two branches of geography, namely physical geography, and human and economic geography:

There exist interrelationships between different geographical phenomena. Physical environment interacts with living organisms in a number of ways. For example, land resources provide soil that supports plant growth.

Sun rays generate heat which leads to the evaporation of water; then water vapour forms clouds and eventually rain. The rainfall feeds plants, i.e., it supports plant growth. Plants are food for herbivores and omnivores such as human beings.

Climate determines the types of plant and animal species that can survive in a particular geographical area and influences human population distribution. Climate also determines human activities like farming, tourism, and settlement. On the other hand, human activities can lead to modification of physical environments, for example, soil degradation, land reclamation, and forest conservation

The Importance of Studying Geography

Geography answers questions about the natural and human worlds. The following are some of the reasons for studying geography:

When we look at the sky at night we see thousands of bright bodies. These are stars and planets. Our Earth is one of the planets. Sometimes we can see a group of stars which form patterns called constellations. In some occasions we can see bright, moving objects. These are called meteorites.

The arrangement of the planets in relation to the position of the sun is called the solar system. The name is derived from a Latin word sol which means sun. The solar system is made up of the sun, planets, moons, natural satellites, asteroids, meteors, comets, dust, ice, and interplanetary space (it contains interplanetary dust and interplanetary gas).

All planets and other bodies revolve around the sun. The sun is the central body of the solar system, and it is the only body that generates its own heat. Bodies that revolve around the sun are kept in their orbits (paths) by the sun’s powerful force of gravity.

There are eight known planets in the solar system. The planets, starting from the one closest to the sun are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.

The four innermost planets in the solar system, Mercury, Venus, Earth and Mars are also called terrestrial planets. They are called terrestrial because they have a compact, rocky surface like the Earth's.

Jupiter, Saturn, Uranus, and Neptune are known as the Jovian (Jupiter-like) planets, because they are all gigantic compared with Earth, and they have a gaseous nature like Jupiter's. The Jovian planets are also referred to as the gas giants, although some or all of them might have small solid cores.

You grew up learning that the solar system consists of nine planets, including Pluto as one as those planets. However, the International Astronomical Union (IAU) stripped Pluto of this status in 2006.

When Pluto was discovered in 1930, it was hailed as the ninth planet in the solar system based on an overestimation of its size. But it looked out of place among the larger planets following the discovery of swarms of ‘ice dwarfs’—icy rocks in the Kuiper Belt, at the very edge of the solar system billions of miles from the sun. This prompted some astronomers to suggest that Pluto could be just another Kuiper Belt Object (KBO), disappointing generations of schoolchildren who grew up learning that Pluto was the smallest planet in the solar system.

On the other hand, this was also a question of meaning or definition of the term ‘planet’. Pluto is clearly big enough for gravity to give it a round shape like any planet (unlike KBOs that tend to be misshapen). It revolves around the sun like other planets. It has an atmosphere and seasons, too.

When the IAU demoted Pluto to a “dwarf planet”, it spelt out three conditions that a celestial body must meet to qualify as a planet: 1) it must be round; 2) it must orbit the sun; and 3) it must have “cleared the neighbourhood” of its orbit (a planet’s gravity sweeps and clears the space around it of other objects). Pluto follows the first two rules, but it hasn’t cleared the neighbourhood of its orbit—which put it in the category of “dwarf planets”. (Of the five known dwarf planets, Pluto, Makemake, Haumea and Eris are located beyond Neptune. The fifth, Ceres, is located in the asteroid belt between Mars and Jupiter.).

Though the solar system has many components, the two most important components of the solar system are the Earth and the sun. The Earth sustains lives of a diversity of living organisms (plants and animals). The Earth contains numerous resources that enable living organisms to thrive in it. The Earth’s atmosphere contains water and air (a mixture of several gases that are used by living organisms for survival). In general, the Earth is the only planet known to sustain life.

The sun is the source of all energy that supports life on Earth. The sun is responsible for water cycle and it is responsible for weather conditions and climate. The moon lights the Earth on some days of the month, though it gets its light from the sun.

The following is an outline of some importance of the sun: