HOT CLIMATE (EQUATORIAL CLIMATE)
Location: The equatorial climate is located within 5˚ north and south of the equator.
- Amazon Basin of South America.
- The Zaire Basin of Central Africa.
- The coasts of West Africa.
Characteristics of the Climate
An equatorial climate exhibits the following characteristics:
- The temperature of an equatorial climate is constantly high all the year round.
- The mean monthly temperature is 27˚C.
- There is very small annual range (less than 3˚C).
- The humidity is high.
- Relative humidity is over 80%, i.e. high relative humidity.
- There is the presence of large amount of clouds in the sky.
- The daily range of temperature is small.
- The annual rainfall is 2000mm or can be over 2000mm or 200cm.
- There is no marked dry season.
- The type of rainfall is convectional.
- It is characterized by intermittent showers caused by the convergence of air masses at the doldrums.
- The Equatorial climate experiences relief rain at mountainous areas.
- It is always hot and wet.
The main features of the vegetation type associated with equatorial climate consist of:
- Equatorial rain forest.
- Evergreen forest.
- Some trees shed their leaves; others bear flowers and others bear fruits simultaneously.
- Trees are not in pure stands.
- Trees exist in different species.
- The trees form three distinct layers; upper, middle and lower layers.
- Mahogany, ebony, walnut, Iroko, Sapele wood climbers, creepers and parasites are the major tree types found.
- The trees have buttressed roots and the shape of an umbrella.
- There is also thin undergrowth, due to tree canopies shielding sunlight.
- Plantation Agriculture: Cash and food crops especially cocoa, rubber, oil palm, etc. are grown in this region.
- Lumbering: The presence of hardwood promotes lumbering in this area.
- Hunting: The local people are also involved in hunting of wild animals.
- Fishing: This is done because of the presence of many rivers.
HOT CLIMATE (TROPICAL CONTINENTAL, SUDAN CLIMATE)
Location: This climate is located between 5˚ – 20˚ south of the equator.
Areas: The climate is found in
- Central America.
- North Western part of South America.
- Interior upland of Brazil, Bolivia.
- West Africa.
- Part of East Africa.
- Parts of India and South East Asia.
- Northern Australia.
Features of the Tropical continental climate:
The savanna lands are hot all year round and the summer temperature is between 32˚C and 35˚C, while the annual temperature range of 11˚C increases as one move away from the equatorial region. Winter temperature are around 27˚C, and the daily range of temperature is great (28˚C). Days are hot but nights are cold due to cloudless skies. Rain falls occur in summer only and it is convectional type. Rainy season is from May to September in the northern hemisphere. In the southern hemisphere, the rainy season is from October to March and there’s low humidity less than 30%. Rainfall varies within the region-rainfall (from 1219mm in Banjul to 127mm in Khartoum). Rainfall decreases from equatorial region poleward towards the desert fringes.
Vegetation (Savanna vegetation): is presence of all tall grasses and clumps of short trees which are scattered. Trees do not grow very tall, but they are hard, twisted and thorny. These trees have umbrella-shape to protect their roots from the sun. And the grasses are between 1 – 2 meters tall. Grasses are stiff, dry and yellow in the long dry season and the tallest variety is the elephant grass. Grasses are green in summer (rainy season). Some common trees are baobab eucalyptus, kapok, shea butter trees, isoberlina, etc. The trees are deciduous. Tropical grassland has different names according to their location e.g. Campos (Brazil), Ilanos (Orinoco valley) and savanna (Africa and Australia).
- Livestock farming due to presence of abundant grasses and low Tsetse fly infestation.
- Arable crop cultivation of rice, maize, millet, wheat, etc.
- People are also involved in hunting of wild animals.
- Development of game reserves which act as tourist centres.
There are types of cold climates. These are polar climate and tundra climate.
- POLAR CLIMATE
Location: This climate is found around 90˚ North and South of the equator, especially around the North and South Poles.
Areas: Interior part of Greenland, Iceland and Antarctica.
- Temperature is generally very low i.e. below 0˚C.
- Annual range of temperature is minimal or negligible.
- Very little temperature in summer.
- Presence of ice throughout the year, forming ice caps on land.
- Annual rainfall is low (10-15cm).
- Blizzards (or snow storms) are very frequent.
- Winters consist of continuous night and the summers of continuous day.
Vegetation: There is generally lack of vegetation of any sort as the land is ice capped throughout the year.
- Fishing in summer only.
- Hunting of some wild animals by Eskimos.
- Herding of some animals adapted to cold weather.
- TUNDRA CLIMATE
Location: This climate is located around 60˚ – 90˚ north and south of the equator especially around the arctic and Antarctic circles.
Areas: Coastal strip of Greenland, Northern Canada and Alaska, part of Eurasia and Antarctica.
- It has long, cold winters and short cool summers.
- It has constant low temperatures between -29˚C and -40˚C in winter.
- Summer temperature is cool which 10˚C with a large annual temperature range.
- The annual rainfall is about 25cm in summer.
- Presence of snow in winter with low humidity all year round.
- Presence of snow, high coincidence of frost and lots of blizzards.
- There is continuous night in winter and continuous day in summer.
- The natural vegetation includes mosses, lichens, tundra trees and shrubs. These plants are referred to as ‘’Tundra vegetation”.
- Other plants include crowberry, willow, birch, puppy and anemone.
- Semi-nomadism is confined to the coast on fur bearing animals.
- Fishing in summer.
- Hunting by the Eskimos in Greenland where caribou (American deer) is hunted for meat, milk and skin.
There are two major types of desert climates. These are:
- Hot desert climate.
- Cold desert climate.
- Hot Desert Climate
Location: Hot deserts of the world are located on the western coasts of continents within latitudes 15˚ and 30˚ North and South of the equator.
Areas: Sahara desert (North Africa), Arabian Desert (Arabia), Iranian desert (Iran), Thar Desert (India), Namib and Kalahari desert (South Africa), Great Australian desert (Australia), Atacama desert (South America) etc.
- High temperatures between 30˚C and 60˚C.
- Aridity or rainlessness is common.
- Annual range of temperature varies from 9˚C to 20˚C.
- Annual rainfall is about 250mm.
- High rate of evaporation.
- Deserts are associated with cold currents.
- The relative humidity is very low.
- Vegetation in deserts is sparse or scanty.
- Common vegetation includes grass, shrub and herbs.
- Most plants are xerophytes (drought resistant plants) like thorny bushes, the bulbous cacti, wiring grasses, date palm and acacia.
- Some plants are halophytes (salt tolerant plants).
Adaptation of plants to Desert Climate
- Possession of long roots to search for water in the soil.
- Presence of few and wiring leaves or no leaves at all to prevent transpiration.
- Presence of wax on leaves to prevent transpiration.
- Some possess thick succulent stems e.g. cacti to store excess water.
- Some shed their leaves during drought.
- Food gathering e.g. fruits.
- Nomadic hunting for wild animals.
- Nomadic pastoral farming e.g. rearing of cattle.
- Crop production like cotton, rice, sugar cane, millet etc. with the aid of irrigation.
- Cold Desert Climate
Location: Cold deserts are located or found in the interior of the continents around 45˚- 60˚north and south of the equator.
Areas: This climate is found in interiors of Eurasia, North America and in Patagonia (South America).
- The climate is characterized by hot summers and cold winters.
- Winters are cold with temperature below -7˚C while summers are hot (38˚C).
- Diurnal temperature range is about 35˚C while annual range is 40˚C.
- Rainfall is low (25cm) and unreliable due to long distance from the sea.
- Most rain occurs in late winter and early spring.
- Presence of short grasses.
- Presence of drought resistant plants with woody stems and needle-like or spiny leaves to reduce transpiration.
- Food gathering.
- Nomadic herding.
- Little cultivation of crops.
WARM TEMPERATE CLIMATE
Western Margin (Mediterranean Type)
Location: The climate is confined to western portion of continental masses between 30˚ and 45˚ north and south of the equator.
Areas: North Africa (Tunisia, Morocco, Libya), South West of South Africa, Central Chile, California, Southern Australia, France, Spain, Italy.
- A dry warm summer of between 21˚C – 27˚C.
- Abundance of rainfall in winter with mean annual rainfall of 6000-800mm.
- Bright, sunny weather with hot, dry summer and wet mild winter.
- Prominence of local winds around the Mediterranean Sea such as Sirocco and Mistral.
- The dominant vegetation is the evergreen woodland such as Oak plants used for cork making.
- Presence of evergreen coniferous forest such as pines, firs and cedars.
- Presence of Mediterranean bushes and shrubs such as acacia, laurel, rosemary and macquis.
- Presence of grasses.
- Orchard farming: Wide range of fruits such as orange, grape, lemon, etc. grown.
- Viticulture: This is the cultivation of grape fruits.
- Crop production such as wheat and rice using irrigation.
- Livestock farming, especially transhumance.
- Wine production from fruits.
WARM TEMPERATE CLIMATE
Eastern Margin (China Type)
Location: The climate is found between 20˚ – 40˚ north and south of the equator.
Areas: Found in eastern margins of continents in China, South East U.S.A, Mexico, Natal (South Africa) and Australia.
- It has a warm wet summer and cool dry winter.
- Mean monthly temperature is between 4˚C and 26˚C.
- Annual temperature range is 25˚C.
- Annual rainfall is between 6000 – 1500mm.
- The climate supports luxuriant vegetation.
- Presence of both evergreen and deciduous forest e.g. eucalyptus.
- Presence of conifer like pines and cypresses.
- Presence of grasses, ferns, lianas and bamboo.
- Intensive farming, especially in cereal crops like rice in China, corn, cotton, etc.
- Mechanized agriculture through the use of irrigation.
- Livestock production in cattle and sheep.
COOL TEMPERATE CLIMATE
Western Margin (British Type)
Location: This climate is found between 45˚ and 60˚ north and south of the equator.
Areas: Found in Britain, France, Belgium, Netherland, Denmark, Norway and British Columbia.
- It has warm summers and mild winters.
- Temperature varies from 4˚C – 17˚C.
- Annual temperature range of 13˚C.
- Annual rainfall is between 600-800mm.
- Presence of deciduous trees that shed their leaves in cold season.
- Presence of temperate hardwoods such as oak, elm, ash, birch, beech and eucalyptus.
- Cultivation of vegetables like lettuce, cucumber, beet root, tomato, cabbage, etc. around the cities known as truck farming in U.S.A. and market gardening in Europe.
- Mixed farming which involves the growing of crops like wheat, rice, barley and animal rearing like cattle, sheep and goat.
COOL TEMPERATE CLIMATE
Eastern Margin (Laurentian Type)
Location: This climate is found between 40˚ and 50˚ north of the equator.
Areas: Found in north eastern part of North America, North East Canada and Northern Asia.
- It has cold, dry winters and warm, wet summers.
- Temperature varies from 21˚C – 27˚C.
- Rainfall varies from 700 – 1600mm.
- Rainfall throughout the year.
- Presence of temperate coniferous forest with trees like fir, spruce and larch.
- Presence of deciduous forest like oak, beech, maple and birch.
- Lumbering, due to the presence of hard wood and soft wood.
- Cultivation of arable crops like maize, rice, oats, barley.
- Livestock farming in cattle and sheep.