Geography, Areas & Climate of Tanzania
A Brief Overview of Tanzania
The United Republic of Tanzania, the largest in the East African Community, spreads out from the western shore of Lake Tanganyika stretching east to Dar es Salaam on the coast of Indian Ocean. Along its western border is the trough in which the great lakes of Africa lie, at the north being Lake Victoria, on the west Lake Tanganyika – the longest freshwater lake in the world – and south Lake Nyasa, almost as long. Both are very deep and are more like mighty rivers than lakes. The greater part of Tanzania is a high and comparatively healthy plateau with a low plain bordering the ocean. The back of this the land rises, opening up to woodlands and magnificent savanna plains covered with grass and bush. One of Tanzania’s most remarkable geological features is the Great Rift Valley in the north-eastern regions of the country. Two branches of the Rift Valley run through Tanzania: The western branch contains Lakes Tanganyika, Rukwa and Nyasa; while the eastern branch ends in northern Tanzania and includes Lakes Natron, Manyara and Eyasi. Mount Kilimanjaro lies on the northern border of Tanzania, halfway between Lake Victoria and the Indian Ocean. It is only a few miles south of the equator, yet, its top, the highest in Africa, is always covered by snow. Kilimanjaro is one of the highest of the world’s mighty mountains. It ends in two peaks, which viewed from a distance resemble a saddle, the taller one (known as Kibo) rising far above the other and each peak is a crater. Once the most valued of the German territories in Africa, and about twice the size of Germany in Europe, it is fairly well-populated, with well over 120 tribes. Administratively, the mainland of Tanzania is divided into 20 regions and Zanzibar into 5 regions. Each region is subdivided into districts. Republic of Tanzania borders Kenya and Uganda in the north; Congo, Rwanda, Burundi and Zambia in the west; and Malawi and Mozambique in the south.
Salient Features of Tanzania
- Surface Area: 940,000 km2
- Number of Districts: 169
- Major Lakes: Victoria, Tanganyika, Nyasa, Rukwa, Natron, Eyasi, Manyara
- Date of Independence: December 9th, 1961
- Current Population: 57 million
- Official Languages: Swahili and English
A Look Into Selected Districts of Tanzania
Bukoba is the chief town on the western side of Lake Victoria and the capital of Kagera Region. It is situated in the most north-westerly part of Tanzania, 1,400 kms from Dar es Salaam by road. Its position and the impaired communication means that it is isolated from the rest of the country. In spite of that, Bukoba District is an important part of Kagera Region and Tanzania because it is very productive. Tin is mined at Kyerwa and several cash crop are grown including coffee. Bukoba is made up of the east facing escarpment near Lake Victoria and plateau country inland. Between the ridges and the flat topped plateau are flat floored and sometimes marshy valleys. Along the lakeshore there are occasional rocky highlands, but mostly it is an area with relatively narrow lake plain with few deltaic areas, where rivers have deposited their alluvium at the edges of the lake. Located just south of the equator and lying close to an enormous water body, the climate of Bukoba could be described as equatorial with temperatures modified by altitude. It lies at an altitude of 4,000 feet (or 1,220 metres) and more, and it is, generally speaking, wet, since it receives over 2,000 mm of rain each year. More important than the total figure, as far as the coffee growing is concerned, is the fact that no month is dry, so that it rains throughout the year. Even so, there are two salient periods of heavier rains in March-April-May and November-December. These two wetter seasons are the ‘Long and Short’ Rains.
What gives Bukoba its very high rainfall is its closeness to Lake Victoria and the direction taken by the main winds. The short rains are the easiest to understand since they caused by the north-east trades, which have blown across part of the Indian Ocean and Kenya. When they reach the north-eastern edge of the Lake Victoria, these warm winds evaporate moisture from the surface of the lake. By the time they reach Bukoba, on the western side, the winds are saturated with moisture and heavy rainfall occurs as soon as land is reached. The Long Rains of March, April and May are caused in a different way. Most of the rain during these months is convectional. The strong heat of the sun causes air to rise; as it rises the air cools and rain may fall. Because Bukoba is very near the lake, the air that is made to rise will be saturated with moisture. Hence the local heating by the sun causes convectional storms which bring heavy rainfall. In addition, the south-east trade winds blow during these months. As these winds cross the lake from the south-east they evaporate moisture as rain when they reach the western side of the lake. If we now look at the temperature, the area is almost always hot year-round (24-28 degrees Celsius), reflecting an equatorial climate.
Tin Mining near Kyerwa
Kyerwa is a town located close to the Tanzania/Rwanda border; it is situated about 120 kilometres west of Bukoba. There are many small individually owned tin mines nearby, most that use inefficient and traditional methods to produce very little tin, but there is one substantial mine that produces about one third of Tanzania’s output. Kyerwa Mine was opened in 1925, just one year after tin ore had been discovered. The mine is located along a river known as Grey Tin Creek and the tin is found in river deposits of cassiterite. Originally the tin settled in reefs of quartz, which is found in the crystalline rocks of the plateau. In the case of the Kyerwa Mines the reefs are found in the Kaborishobe Hill area, which is drained by the Grey Tin Creek. This river erodes away the crystalline rocks and the quartz containing tin and deposits them downstream. It’s these downstream deposits that are mined. Since the mining began the mine has slowly expanded and has been owned, at various times, by several different companies. During the period 1938-1948 an average of over 100 tonnes of concentrated cassiterite (tin ore) was produced each year. In 1955 the Malayan company, which then owned the mine, decided upon a rapid expansion of mining. To do this they built a new treatment plant which was capable of handling 1,000 tonnes of ore each day. To provide power for this an electricity power line was built from the hydro-electric station 56 kilometres away at Kikagat in Uganda. Unfortunately, the expansion of mining was not completely successful and the mine acquired new owners in 1969. Following this exit, mining was carried out using open caste methods, that is, the tin ore is dug out straight from the surface without the need to dig shafts and tunnels. Since mining is done at the surface it means that heavy moving machinery, such as excavators, can be used. Once the ore has been mined it is taken to the treatment plant where the rock is crushed twice, firstly by a cone crusher. Good grade tin ore contains 76% tin and 24% waste.
Coffee Growing in Bukoba District
This area is very important for growing of Robusta coffee, which forms almost two-thirds of the agricultural produce ingathered in the region. Most farms are plantations, therefore, grow coffee and the Tanzania Government has over the years encourages farmers to grow more of other crops, like tea and sugarcane, in order to diversity production. Why is the area so suitable for coffee? There are many reasons, of course, but they are mostly depend upon the climate and the physical features of the area. Coffee requires high temperatures and well distributed rainfall. It also requires high humidity and because Bukoba is near Lake Victoria it is always present. Finally, the coffee needs good, well drained soils and these are found in the area, especially on the sloping hillsides. Coffee is not usually grown in the valley bottoms because of poor drainage and some occasional swamps. It takes about four to five years after being planted in the nursery, and three years after transplanting, for the first coffee beans to be harvested from a bush. It is not until the bush is eight years old, however, that it really produces heavy crops. Once it is producing well, a good bush will give a large crop for fifteen or twenty years after which it will be dug up and replaced with a young bush. The coffee beans, which take eight months to mature, are wholly gathered by hand and it is essential that there should be many workers available for harvesting. The beans are then sun dried and the pulp and skin is removed in local pulperies. Bags of coffee are then transported, either by the co-operatives or the plantations, to the treating factories. In the factories, the coffee beans are tuned into soluble coffee. The beans are first roasted and then ground into a fine powder. To remove insoluble part of the coffee the powder is mixed in a water solution; the insoluble parts are not dissolved and therefore can be removed. The soluble coffee is dissolved in the water and this water is evaporated from the coffee solution so the dry soluble coffee can be obtained.
About 160 kilometers southeast of Mwanza, in the northern region of Tanzania, are to be found the Mwadui diamond mines near Shinyanga. On the other hand, Musoma is located about 160 kilometres northeast of Mwanza. The Mwadui-Mwanza-Musoma Region is historically Tanzania’s major cotton growing area. Mwadui is the site of Tanzania’s most important mineral deposit – kimberlite rock, which contains diamonds. The nature of the terrain around the mines is completely flat except for one or two small hills. It is part of a great plateau, made of crystalline rocks, which stretches across most of central Tanzania. This plateau has an average height of between 3,800 feet (1,160 metres) and 4,000 feet (1,220 metres). Of course, this plateau is not perfectly flat. For instance, in the north east there are several hills, one which reaches 4,540’ (1,383 metres). Conversely, in the wide, shallow valleys, created mainly by river action, the land falls to below 3,600 ft. (1,097 metres) as you head further southwest of the area.
Further north, the scenery around the Mwanza-Musoma section of the Lake Plateau is rather different. The plateau is no longer flat but dissected. Heavier rainfall has made the rivers which flow into Lake Victoria very powerful agents. These rivers have eroded the plateau into flat topped hills separated by wide and, sometimes, marshy valleys. In many ways the landscape is very similar to that found around Buganda, Uganda and Nyanza in Kenya. The climate of the Mwadui-Mwanza-Musoma Region, which is about 320 kilometres long, with one end found near the very large lake, while the other is located far from any source of moisture, has considerable variations especially with the rainfall. Mwanza has one wet and one dry season. The rainy season is continuous from October to May, with a much drier season during the months between June and September. In other words, the second dry season of December and January, which is found in those parts of East Africa set nearer the Equator, is missing. Mwanza has a climate that is more tropical than equatorial. There are still some equatorial influences since within the eight months long wet season there are two periods of heavier than average rainfall. March-April and November-December are these two wetter periods. It therefore suffices to say that Mwanza has a tropical climate with one dry and one wet season, but within the wet season there still exists two periods when the rainfall is particularly abundant.
Cotton Farming around Musoma
“Cotton is Tanzania’s second largest export crop after coffee and Africa’s fourth-largest producer of cotton after Mali, Burkina Faso and Egypt. About 14 million people or 40% of the total population derives their living directly or indirectly from cotton that is grown by an estimated 500,000 small holder farmers with approximate cultivated area of 400,000 hand crop of 360,000 tons and having a high potential for growth through sustainable farm management, contract farming, credit facility, adequate and efficient provision of farm inputs, etc. Presently, 70% – 80% of Tanzania’s annual cotton production is exported” – METL Group. Cotton is grown by the local farmers as their main cash crop; usually the farms are small, only 2 or 3 hectares in size. Often these farms are fragmented – this means that the fields owned by one farmer are not found together, but are distributed over a wide area. On the larger modern farms which are highly mechanized, cotton is grown in a slightly different method from that of the small farmers. Some of the larger farms are found near Kibara, on the shores of Lake Victoria, about half way between Musoma and Mwanza. Overall, cotton in Tanzania is sold through well organized cooperatives, mainly between June and July. The ploughing is done in November and December; the cotton seeds being planted at the end of December. During March and April the cotton is weeded and by May the crop is ready for picking. From here, cotton is then graded based on lint to whether it’s white (healthy) or coloured (diseased).
Williamson Diamond Mines at Mwadui
Located a few kilometres north west of Shinyanga, the Williamson Diamond Mines is relatively large, partly because the outcrop of diamond bearing rock is probably one of the largest in the world. Millions of years ago a volcano was formed at Mwadui. The molten volcanic rock came up from inside the earth through a volcanic pipe. Eventually the molten rock in the pipe became solid and formed a volcanic plug. Since then the volcano has gradually been eroded away until all that is now left is part of the volcanic plug. It is this plug, made of a rare rock called kimberlite, which contains diamonds. Because the plug is at the surface there is no need for tunnels and shafts; instead the rock is simply dug out from the surface by mechanical shovels. A series of benches are dug, each about 8 metres high. The top bench is made of surface material like black cotton and the lower benches are made of kimberlite rock. Mining has been going on for nearly 80 years, beginning in 1940, so that lowest benches are now about 75 metres below the original ground level. Sometimes the rock is so hard that it must be broken up by explosives before the heavy machinery can dig it.
Heavy diesel lorries transport the ore from the benches to a crushing station, located near the benches, where the rocks are broken up until they are less than 100 mm in diameter. These small rocks are loaded into a long conveyor belt to the treatment plant, which uses advanced methods to remove the diamonds from the ore. After scrubbing, cleaning and sizing, the ore is passed through heavy media separators, where heavy diamonds and a few other heavy minerals sink to the bottom. The lighter materials float and can be removed. 98% of the waste rock is removed by the separators. The heavy minerals and diamonds are now milled with steel balls. Diamonds are the hardest of all minerals and are not affected, but the movement of the steel balls reduces the softer minerals to pulp. The coarse material are made wet and are placed on endless belts, which are covered in a layer of grease. The minerals roll off the grease because they are wet, but the diamonds are water repellent and therefore stick to the grease. The fine particles are passed between positive and negative electrodes, the diamonds which are very poor conductors of electricity being split away from the waste material. It takes ten million kilograms of ore to get half a kilogram of diamonds! The mine and treatment plants are situated far from centres of population and so the Williamson Diamond Company has built its own town, Mwadui, which has a population of about 23,300. Almost all the diamonds are exported, and diamonds are among Tanzania’s top-ten most important export.
This north west region, dominated by the southern slopes of Mount Kilimanjaro and Mount Meru, is important for tourism, farming, industry and commerce of Tanzania. Agriculture varies with height of position on the side of these two big mountains, so that the forests occur on the higher slopes, intensive cultivation on the middle slopes, plantations on the lower slopes, and little cultivation on the drier plateau areas. The mountains attract relief rainfall, so that the further one moves from the mountains the poorer agriculture becomes. Traditionally, the farming around the southern slopes of both Mount Kilimanjaro and Mount Meru consists largely of shamba cultivation of bananas and maize, with coffee, tea and sisal as the cash crops. Coffee, therefore, dominates the cash crop farming of this area, which is interesting since the world price of coffee in the 1980-90’s had gradually fallen. Because of this the Tanzanian Government had attempted to discourage the expansion of coffee land. Since the acres of coffee were not being expanded in these early days, development took place in other crops. Around Arusha wheat and maize became important and on the slopes of Mount Kilimanjaro the growing of maize, paddy and cotton were encouraged. Arusha was selected as the headquarters of the East African Community owing to centrality, leading to the development of large new administrative buildings. Early on, industry consisted mostly of agricultural processing, but its selection as the capital of East Africa encouraged industrial expansion. Electricity to all the industries and to the public in Arusha is supplied from Nyumba ya Mungu Power Station. In addition, the establishment of the International Kilimanjaro Airport, encouraging tourism to the region, was a further impetus for growth. The rise of Arusha can, therefore, be based on its selection as the headquarters of the East African Community, its vast industries and its potential for tourism.
Dar es Salaam: Capital of Tanzania
Dar es Salaam is by far the largest town, the biggest port, the primary industrial town and the most important communication centre for the whole of Tanzania. It is not surprising, therefore, to find that Dar es Salaam is also the capital and major administrative centre. The 2020 index put its population at 6.7 million; a 5.24% increase from 2019. Because of its important functions, Dar es Salaam is growing rapidly, both in area and population. The most obvious fact about its physical geography is that it lies at the coast. A more accurate description would be to say that Dar es Salaam is sited on the northern and western sides of a ria. A ria is caused by sub-mergence; it is, of course, a drowned river valley caused by a rise in sea level or the land sinking below the ocean. There climate of the area is pleasant almost all year round, and being almost seven degrees south of the equator, its climate is not really equatorial. The rainfall is relatively heavy, concentrated around the months of March-April-May. Temperatures are always high, but there is a noticeably cooler period from June until September, which coincides with, and partly causes, the long drier season. In fact, the climate here is similar to that of Mombasa along the Coast of Kenya. Similar to its opposite number and most coastal towns in East Africa, Dar es Salaam was founded by the Arabs. Sultan Seyyid Majid decided to build a city on the mainland and it was begun in 1865. Its population and importance grew slowly until, by 1891, it was large enough to be chosen as the main port and communications centre for German East Africa. From this time onwards it grew rapidly and, during both the German and British administration it was the obvious choice as the capital of the Republic of Tanzania. Most of the early settlement, especially during the early colonial period, was in the area around the harbour creek. Later the town expanded to districts like Magomeni, Kariakoo, Llala and Keko, which are away from the older township. The high class residential areas – those used by the colonial administrators and more recently by state officials and expatriates – are set at Oyster Bay north of Msimbazi Bay and, to a lesser extent, at Upanga. Dar es Salaam is the second largest port in East Africa and, although smaller than Mombasa, handles three times as much trade as all the other Tanzanian ports together. Within Tanzania, it dominates both the import and export trade.
Pemba and Zanzibar Islands
Tanzania’s offshore consists of two main islands – Pemba and Zanzibar – and many smaller ones. These islands are very low, rarely rising above 300 feet or 100 metres, and are made of coral. For over a hundred years they have been famous for the growing of cloves and coconuts; although these two crops are still important, many newer crops are now being cultivated. Many people live on these islands: Pemba Island has an estimated population of 400,000, with its largest town, Chake-Chake, having a population of 20,000; while Zanzibar Island has an estimated population of 1.3 million. The population density on both this islands is about 10 times higher compared to the mainland. Pemba Island has an area of about 984 km2 and is therefore smaller than Zanzibar Island, with an area of 1,657 km2. Both islands are located close to the coast of Tanzania; Pemba lies about 64 kilometres east of Tanga and Zanzibar Island is less than 48 kilometres north of Dar es Salaam. About 48 kilometres of Indian Ocean separates the two islands, and Pemba and Zanzibar Channels separate the islands from the mainland. The channels that separate the two islands from the mainland are only 20 metres deep in some places, although in other parts they are as deep as 60 metres. It is almost certain that at some point in history these channels did not exists and the islands were once part of the mainland. It is thought that a series of nearly parallel faults developed and the land between them sank to form the Pemba and Zanzibar Channels. This, of course, did not happen quickly, but over a period of thousands of years. Also the sinking did not happen continuously, instead there were period when the land was sinking and periods when it did not move. In time, however, it sank to its present level and it is probable that the sinking has not yet stopped. Along with this sinking was also tilting. As the channels sank so the two islands were tilted, so that the western sides of the islands tilted upward and are higher than the eastern sides.
Zanzibar Island, reachable by air from Dar es Salaam in 20 minutes or by ferry, is one of Tanzania’s most popular destinations. There are also daily flights from Nairobi via Mombasa and Tanga, and daily passenger steamship services, the sea journey taking about two hours. On the eastern side of the island are many good places to stay near the seafront. Visitors don’t need to take formal clothes to Zanzibar. The island is a place of informality and relaxation. Apart from the unrivalled beaches, places to visit include the handicraft showrooms; the Old Fort; Beit-el-Ajaib (the House of Wonders) which was built in 1883 by Seyyid Bargash; the People’s Palace; which was the former Sultan’s Palace; the Hindu Dispensary; and the old slave market. Other interest include the fruit market, Livingstone’s House, the Maruhubi Palace ruins, Kibweni Palace, which are all well worth a visit, and the Kijichi coconut plantation, where guides explain to visitors the short history of the coconut, and how copra is obtained. The latter also take one to see clove trees, cinnamon trees, cocoa and coffee plantations. Zanzibar has a weighty history too. The Sultan of Zanzibar – an Arab leader and descendant of chiefs who sailed from Arabia centuries ago and conquered a large part of East Africa – once controlled the territory that later came to be known as German East Africa, and there through his chiefs governed the affairs of the mainland. In the ensuing Scramble for Africa, Zanzibar Island remained the property of the Sultan, under the protection of Great Britain. Zanzibar was the capital of the Sultan, from where he controlled far-reaching trade in spices, slaves and ivory. At the same time, many kind of goods were shipped there to be taken over to the mainland for trade with the natives. People from India, Arabia and Europe settled here many centuries ago to trade in businesses and helped grow the city, which was for at least two centuries the largest city in East Africa. For the history buff, the castle of the Sultan and the influence of building from early settlers is worthwhile. “The port city of Stone Town dominates the west coast, and although the beaches of Mangapwani, where slave caves are visible at low tide and nearby, Bububu are less than half an hour’s drive away.” – TTB
Njombe: The Southern Highland of Tanzania
Njombe is located in the Southern Highlands of Tanzania, lying at about 6,000 feet (1,830 metres), but a little further west they reach about 9,700 feet (2,950 metres). Njombe Region that has an area of 20,460 km2 has a population of 702,097; in 2012. Bearing in mind that these highlands are cooler and wetter than most regions in Tanzania, agricultural production is high. The main cash crops are avocado, tea, tobacco and wattle. Unfortunately pyrethrum, proving not be a profitable crop to grow, has almost been faced out. Although there are some minerals available in Njombe Region, much of the development arises from its agricultural productivity, and its upcoming tourist sites likes Nyumba Nitu Forest, Luhuji waterfall and several historic sites (including a Catholic Cathedral and a Lutheran church). In most of the region, however, the land is covered with forest, some of which is in reserves. Because forests are important both as a natural resource for timber and also as protection against soil erosion, the forests are continually enlarged and reorganized so that the timber can be removed and marketed as required. The main timber area is at Sao Hill, which is halfway between Njombe and Iringa. Additionally, the area is endowed with mineral deposits, which include iron ore discovered at Liganga. There are also sizeable deposits of bituminous coal in the Ruhuhu Valley. Even so, Njombe is mainly agrarian; the mineral that are found here are yet mined in large amount.
Weather Guide to Tanzania
The Northern Area (Arusha and Kilimanjaro Regions, Lushoto and Handeni Districts) – With the exception of the mountainous areas rainfall is everywhere less than 30 inches, the majority of which falls from mid-March to end of May and mid-October to mid-December, during the night and early morning in the former season and during the afternoon and evening in the latter. The hottest months are from January to March with temperatures rising above 30 degrees C. over the plains on most afternoons. In the mountainous areas the heaviest rain falls between April and May. From April to October it is relatively cool and generally cloudy, most of the rain falling overnight and in the early morning. From November to March temperatures are higher and rainfall occurs chiefly during the afternoon and evening. Areas near Lake Victoria (Kagera, West Lake, Mwanza and Mara Regions) – The rainy season extend from November to April, the wettest months being March and April. In the east and south it is dry from june to September but in the west July is the only dry month. Showers and thunderstorms are experienced in the eastern districts from afternoon until late night, but west of the lake most rain falls during the night and early morning. Lake breezes in the afternoon maintain moderate temperatures. The hottest months in the east and south are September and October when afternoon temperature sometimes exceeds 30 degrees C. The Central and Western Areas (Shinyanga, Kigoma, Tabora, Central and Morogoro Regions) – In these regions the seasons are characteristic of the greater part of Tanzania, the single rainy season lasting from November to April. Heavy showers develop during the later afternoon, persisting into the night and early morning. Annual rainfall in the west is about 30 and 40 inches, but in the central area it averages only 20-30 inches. in the dry season hot afternoons, with temperatures in the lower 30’s (degree Celsius) are compensated by relatively cool nights and mornings.
The North Coast Areas (Tanga, Pangani District, Kibaha and Coast Region north of Dar es Salaam) – In the low-lying coastal plain during the wet season, between November to May temperatures may rise above 30 degrees C. almost every afternoon and may not fall below 24 degrees C. during the night. The high humidity and temperatures together make conditions rather unpleasant at this season. Rainfall occurs chiefly during the night and morning. The South Coast Areas (Coast Region south of Dar es Salaam, Kilwa, Lindi, Mtwara Districts) – In this area the hot, unpleasant and humid season of the rains is December to April. Most of the rains occurs during the night and morning so that afternoons are generally fair. It is much drier and cooler from May to November, the mean air temperature during this season being about 25 degrees Celsius. The South Highlands Areas – In this region the rainy season is November to April, January being the wettest month. Tukuyu District at the northern end of Lake Nyasa has heaviest rainfall of any part of East Africa, over 100 inches or 2,500 mm. Temperatures are relatively low in the higher stations, Mbeya being only 18 degrees Celsius. The Southern Inland Areas (Ruvuma Regions: Maasai, Nachingwea, Newala district) – The annual rainfall in these areas is generally between 30 and 40 inches, and the conditions are often oppressively hot in the wet season, between November to April. Rain usually starts in the afternoon and continues until late evening. Afternoon temperatures in the wet season are generally between 20 degrees C. and 33 degrees C. (depending on altitude) but in dry weather, June to August, the mean maximum is about 6 degrees C. lower.