Tropical zone lies between 0° to 30° latitudes in both hemisphere of the earth. As this zone receives direct sun rays, it has hot climate. Amount of rainfall differs according to the place and time. On the basis of temperature, air pressure and amount of rainfall, there are four climates in this climatic zone. They are:
1. Equatorial Climate
2. Tropical Grassland Climate or Sudan type of Climate
3. Tropical Desert Climate
4. Tropical Monsoon Climate
1. Equatorial Climate
a. Climatic Region:
It extends from 0° to 5° latitudes in both hemispheres. It is found in Amazon basin, Congo basin and South East Asian Islands. As Amazon basin is the main region of this climate, it is also called Amazon Type of Climate.
b. Climatic Characteristics: It is hot throughout the year as the sun rays fall straight here. Convectional rainfall with thunder and lightning takes place every day. There is no change in season. The time of day and night is equal. There is hot, wet and humid climate all over the year.
c. Natural Vegetation and Animals:
This region is appropriate for crops and forests because of enough rainfall and wet climate. Dense evergreen forest is found here in which various types of large and tall trees and creepers are found in huge amount. The dense evergreen forest in Amazon basin is called Selvas. The trees are tall, broad-leaved and evergreen. About 90% of the animal species found in the world is found in the equatorial forests. Many reptiles and amphibians and animals like snakes, lizards, different kind of frogs, chimpanzee, leopard, gorilla, crocodiles and hippopotamus are found here.
d. Economic Activities: The major occupation of the people in this region is agriculture. Major agricultural productions are paddy, coconut, sugarcane, maize, coffee, tea, spices, cocoa, banana, tobacco, etc. The inhabitants of forest live on hunting wild animals, collecting wild fruits and edible roots and medicinal herbs, fishing, cutting trees, etc. Wood, medicinal herbs, bones and skins of animals are the major forest products.
e. Effect on lifestyle: The lifestyle of the people in equatorial climatic region is primitive and very difficult due to the hot and wet climate. Red Indians of Amazon basin and Pygmies of Congo (Zaire) basin are the indigenous nomadic tribes of this climatic region. As industry and commerce are not well developed here, the people earn their living from hunting and gathering, animal husbandry and temporary farming. Though the climate is suitable for agriculture, it is not appropriate for human settlement. But in the South East Asia, people have made advancement due to influence of European contact and civilization. Indonesia, Malaysia and Singapore are its examples. The population density is also high there. The people are involved in trade, industries, tourism, etc.
2. Tropical Grassland Climate
a. Climatic Region: Tropical grassland climate is found between 5° to 20° latitudes in the inner part of the continents.Sudan, South African plateau, Brazilian plateau, Orinoco basin, inner part of northern Australia, Deccan and Shan plateau are the main regions of this climate. Asthe main region of this climate is Sudan of Africa, it is also called Sudan type of Climate and Savanna Grassland.
b. Climatic Characteristics: Summer is very hot and winter is warm and often dry in this region. Trade wind causes rainfall during summer ranging 50 to 150 cm. As this climatic region is between the equatorial region and tropical desert region, the rainfall is more towards the equatorial region and less towards the tropical desert region.
c. Natural Vegetation and Animals: Rainfall is not enough to grow a dense forest. So, only the long grasses are found here. The tropical grassland is called Llanos in Orinoco basin, Campos in Brazilian plateau, and Savanna in central African region. Savanna grassland is also called “Zoo of the World” because varieties of animals and birds are found in this region. This region is the home of many herbivorous and carnivorous animals like deer, gazelle, antelope, zebra, giraffe, elephants, lion, tiger, leopard, jaguar, hippopotamus and rhinoceros. Some of the common birds found in this region are Ostrich, Emus, Cassowary, Rhea, etc. These birds are mostly flightless and live in the region where there are few trees.
d. Economic Activities: Agriculture is the main occupation of people living in the areas where enough water and irrigation facility is available. Oilseed, cotton, tobacco, sugarcane, maize, wheat, etc are the major agricultural productions of this region. The indigenous tribes live their life by hunting wild animals. So this region is also called “Land of Big Games”. Cattles rearing is another occupation of people. Wool, leather, dairy product, etc are the animal production of this region.
e. Effect on lifestyle: As this region experiences hot and dry climate, it is not appropriate for the human settlement. Most of the population is still living in primitive way. Some indigenous tribes of Central African region like Masai and Hausa are living their nomadic life. The level of economic development is not uniform all over this region. There are some pastoral groups who depend on animal husbandry and subsistence agriculture. The population density is very low. However, there is higher possibility of tourism development. Most parts of tropical grassland have been converted into National Parks and Wild Life Reserves. Nowadays, thousands of tourists visit there every year for entertainment and study. Animal films are made in this region. Modern farming and agriculture is rapidly developing in this region. Commercial crops like cotton in Sudan, coffee and tea in Kenya, tobacco in Zimbabwe are grown in large scale. Because of this, the Savanna region has great scope for development.
3. Tropical Desert Climate
a. Climatic Region: Tropical desert climate is found roughly between 20° to 30° latitudes in the western part of the continent. It is the route of dry trade wind. It is also known as “Hot Desert”. This type of climate is found in Sahara and Kalahari Desert in Africa, Iranian and Thar Desert in Asia, Atacama Desert of South America, Arizona and Mexican Desert in North America, the Great Australian Desert in Australia. As this type of climate is mainly found in Sahara region of Northern Africa, it is also called “Sahara type of Climate”.
b. Climatic Characteristics: This climate is very dry and hot. Due to the quick heating and cooling nature of sand, there is higher gap between the maximum and minimum temperature. The temperature at day rises up to 49°C and at night it falls down to 10°C. There is very less rainfall because there is no influence of rain bearing wind blowing from sea.
c. Natural Vegetation and Animals: Trees cannot grow there due to the lack of rainfall. Dry and hot climate supports only thorny plants like cactus to grow in this region. Such plants have very long roots to reach the underground water. The plants like cactus have tiny, waxy and leathery leaves to prevent the loss of moisture. Some animals such as camel can live without or with very little water for a long time. They store fat in their humps which can be broken down to provide water and energy. Camel furs can trap a layer of air which acts as insulator and help keep their body cool during day and warm during night. They have very tough lips and tongue which enables them to nibble (chew) thorny desert vegetations. They have thick eyebrows to protect them from sand storm and broad feet to enable them to walk easily on the sand. The desert fox, snakes, lizards, gazelle, hyenas, donkeys and horses are also found in the desert.
d. Economic Activities: The main occupation of the people in tropical desert is agriculture and cattle rearing. It can only be done in the Oasis where water is available and land is fertile. Wheat, barley, cotton, tobacco, maize, oilseed, sugarcane, etc are the agricultural production of this region.
e. Effect on lifestyle: As the tropical desert climate is hot and dry, it is not appropriate for human activities. So life in the desert is extremely difficult. Agriculture, industry and commerce are not well developed here. Nomadic tribes live in small numbers by hunting and food gathering. In oasis, people have permanent settlements. They live in houses with thick mud walls and flat roofs. The Bushmen of Kalahari Desert, Aborigines of Australian desert and Bedouins of Arabian Desert are the native tribes of hot deserts. A few of the desert areas are attracting immigrants due to rich mineral deposits like petrol and gold. Nowadays development activities are increasing. Construction of infrastructure and businesses are growing rapidly. The people have now started commercial agriculture and animal husbandry by using modern technology. Camel is the most dependable means of transportation in desert area. Therefore, it is also known as the ‘Ship of the Desert’. It can easily walk on sand and live without drinking water for many days. People rear camel for carrying load and for milk and meat.
4. Tropical Monsoon Climate
a. Climatic Region:
Tropical monsoon climate is mainly found between 5° to 30° latitudes in the Southern and South-Eastern part of the Asia. This climate is also found in Northern Australia, South-East Africa, South-West Africa, South- East Brazil, Caribbean region and Eastern islands.
b. Climatic Characteristics:
Here summer is hot and wet and winter is cold and dry. During summer, there is low air pressure over the land and high air pressure over the sea. So summer monsoon blows from sea to land and causes enough rainfall in this region. The annual rainfall ranges from 50 cm to 200 cm depending on the place. As the winter monsoon blows from land to sea, it does not cause rain. Thus, this climate is also known as “Summer Rain Climate”. There are three seasons: summer, rainy and winter. Rainfall is unreliable and the amount fluctuates greatly from year to year.
c. Natural Vegetation and Animals:
Deciduous forest is the main natural vegetation of this region. Sal, bamboo, Sisau, etc are the major species of trees. Besides this, evergreen forest, tall grasses, thorny bushes and scrubs are also found in various parts depending on the amount of rainfall and altitude. This Region is known for its wide varieties of Animals. The climatic condition and natural vegetation
of this region favors the existence of different species of birds, animals and insects. Many wild animals like leopard, tigers, wild buffaloes, wild yaks, Asian elephant, Indian and Javan rhinoceros, elephant, lions, monkeys, langurs, orangutan, gibbons, etc live in this climatic region.
d. Economic Activities:
Tropical monsoon climate is appropriate for agriculture, industry and trade. The major occupation of the people in this region is agriculture. The high air pressure, enough rainfall, fertile soil, plain land, facility of irrigation, cheap labor cost, etc are supporting for the enough agricultural production. Beans, maize, barley, wheat, paddy, etc are the major agricultural products of this region. Cash crops like tobacco, tea, coffee, sugarcane, cotton, jute, etc are also produced. Forest product and animal product are also produced sufficiently here. Paddy is the main crop. There are many mineral industries as
well.
e. Effect on lifestyle: This climate is most appropriate among the climates found in tropical zone. It is suitable for agriculture, industry, trade and human health. It is rich in human civilization and culture. The population density is high. About one-third population of the world lives in this region. This is the common habitation of the people representing different culture and civilization. The regions where human civilization originated and developed on the valley of Rivers Indus, Brahmaputra, Ganges and Irrawaddy also lie in this climatic region.