Geography of West Bengal
Geography of West Bengal, a state in eastern India, is diverse, of high peaks of Himalaya in the northern extremes to where Himalayas are in the north and sea is at the south, with both plains and plateaus covering the remaining region. Location and extent. West Bengal is on the eastern bottleneck of India, stretching from the Himalayas in the north to the Bay of Bengal in the south. It lies between 85 degree 50 minutes and 89 degree 50 minutes east longitude, and 21 degrees 25 minutes and 27 degrees 13 minutes north latitude. The  state has a total area of . With Bangladesh, which lies on its eastern border, the state forms the ethno-linguistic region of Bengal. To its northeast lies the states of Assam and Sikkim and the country Bhutan, and to its southwest, the state of Odisha. To the west it borders the state of Jharkhand and Bihar, and to the northwest, Nepal. The capital of the state is Kolkata, the third-largest urban agglomeration and the seventh-largest city in India. Political geography. There are 23 districts and 5 divisions in West Bengal. The Burdwan Division consists of Paschim Bardhaman, Purba  Bardhaman, Birbhum, and Hooghly;Medinipur division consists of Purba Medinipur, Paschim Medinipur, Jhargram, Bankura and Purulia; the Jalpaiguri Division consists of Alipurduar, Cooch Behar, Darjeeling, Jalpaiguri, and Kalimpong; the Malda division consists of Uttar Dinajpur, Dakshin Dinajpur, Murshidabad and Malda, and the Presidency Division consists of Kolkata, Nadia, North 24 Parganas, South 24 Parganas and Howrah. Each district is governed by a district collector or district magistrate, appointed either by the Indian Administrative Service or the West Bengal Civil Service. Each district is subdivided into Sub-Divisions, governed by a sub-divisional magistrate, and again into Blocks. Blocks consists of panchayats  (village councils) and town municipalities Often the districts north of the Ganges i.e., Cooch Behar, Darjeeling, kalimpong, Jalpaiguri, Alipurduar, North Dinajpur, South Dinajpur and Malda are together termed as North Bengal. The capital and largest city of the state is Kolkata – the third-largest urban agglomeration and the seventh-largest city in India.Asansol is the second largest city & urban agglomeration in West Bengal after Kolkata. Siliguri is an economically important city, strategically located in the northeastern Siliguri Corridor (Chicken's Neck) of India. Other major cities and towns in West Bengal are Howrah, Durgapur, Raniganj, Haldia, Jalpaiguri, Kharagpur, Burdwan , Darjeeling, Midnapore, and Malda. Landforms. Darjeeling Himalayan hill region. Darjeeling Himalayan hill region is situated to the north of the state. This region belongs to the Eastern Himalaya range. The entire Darjeeling district except the Siliguri subdivision and northern part of Jalpaiguri and Alipurduar district falls under this zone. It starts abruptly from the Terai region. The deep gorge of Teesta River, which runs from north to south has divided this mountainous region into two parts: 1. the western mountain ( west part of Teesta) and 2. The eastern mountains ( east part of Teesta). 1. Singalila range: The Singalila range is  located along the border of Darjeeling and Nepal. It separates West Bengal from Nepal. Singalila penetrates into Darjeeling district, being started from Western Sikkim. It has four important peaks higher than 3000m,– Sandakphu (3636m), Phalut (3595m), Sabargram (3543m) and Tonglu (3036m). Among the Himalayan ranges of this region, Singalila range hosts Sandakphu, at , is the highest peak of West Bengal.Kanchenjunga (world's 3rd highest peak), Everest (world's highest peak), Lhotse (world's 4th highest peak) and Makalu (world's 5th highest peak) can be seen from Singalila range. 2. Darjeeling range : Darjeeling range  has risen up steadily from Terai area. Ghum railway station (2258m) of this range is the highest rail station in India. The famous Tiger hill (2567m) is situated at the middle of this mountain chain. Tiger hill is a view point from where Kanchenjunga (world's 3rd highest peak), Everest (world's highest peak), Lhotse (world's 4th highest peak) and Makalu (world's 5th highest peak) can be seen. Three minor chains - Darjeeling Lebong in north, Takdah Peshok in north-east and Bagora Dowhill in south has been started from tiger hill. Sinchal (2615m) is one  of the well known peaks of here. Durpin dara chain holds the highest peak of eastern part, Rishila at . There are two peaks, Renigango (1885m) and chhoto Sinchula (1726m) to the north of Jalpaiguri district. The Buxa hill is located at the east end of this region. Sangchuli is the highest peak of the Buxa hills. Kalimpong town is one of the well known towns of this area. "Note that Darjeeling Himalayan Railway (simply known as toy train) has been listed in UNESCO world heritage sites." Terai region. The ‘'Terai'’ ("moist land") is a belt of marshy grasslands , savannas, and forests at the base of the Himalaya range stretching southwards to about 38 km. Above the Terai belt lies the Bhabar, a forested belt of rock, gravel, and soil eroded from the Himalayas. The Terai zone is composed of alternate layers of clay and sand, with a high water table that creates many springs and wetlands. The Terai zone is inundated yearly by the monsoon-swollen rivers of the Himalaya. The "Terai-Duar savanna and grasslands" is an ecoregion that stretches across the middle of the Terai belt. The Terai-Duar savanna and wetlands are a mosaic of  tall grasslands, savannas and evergreen and deciduous forests. The Terai and Dooars region politically constitute the plains of Darjeeling District, whole of Jalpaiguri and Alipurduar district and upper region of Cooch Behar District in West Bengal. The slope of the land is gentle, from north to south. The general height of the land is 80 to 100 m. The entire region is made up of sand, gravel and pebbles laid down by the Himalayan rivers like the Teesta, Torsa, Raidak, Jaldhaka, Sankosh, Mahananda and several other small rivulets. The Teesta has divided the area into two parts- the western part  is known as the Terai whereas the eastern part is known as the Dooars or Duars. The Dooars region can be further subdivided into the Siliguri or Western Dooars, the middle or Jalpaiguri Dooars and the eastern or Alipur Dooars. North Bengal plains. North Bengal plain start from the south of Terai region and continues up to the left bank of the Ganges. The southern parts of the district Jalpaiguri, North Dinajpur baring some extreme northern regions, South Dinajpur, Malda, Alipurduar and southern part of Cooch Behar districts constitute this geographical region. The narrow land mass in the North Dinajpur  district is known as Mahananda Corridor. This corridor runs north to south joining Malda with the plains of Jalpaiguri, Alipurduar and Cooch Behar. The entire part of North and South Dinajpur is silt laden plain. Mahananda River divides the district of Malda into two parts. The eastern part consists of undulating plains and some tilas and is made up of old alluvium and is a part of the Ganges delta. It is also known as Barind or Barendrabhumi. In contrast to the eastern part, the western part is made up of new alluvium and in this part River Kalindi joins  the Mahananda River. The part of Malda lying to the north of river Kalindi is known as tal. This is a lowland and covered with swamps and beels (small water bodies). Whereas the area south of the Kalindi is a very fertile land and is known as diara. The plain in the south of Jalpaiguri, Alipurduar and Cooch Behar district is also made of new alluvium deposited by numerous rivers like the Teesta, Torsa, Raidak, Jaldhaka, Sankosh, Balason, Punarbhaba, Atrai and several other small rivulets. Rarh region. Rarh is the region that intervenes between the Vajjabhumi and the Ganges Delta . Parts of the districts Murshidabad, Birbhum, Bankura, Purba Bardhaman, Paschim Bardhaman, Purba Medinipur and Paschim Medinipur constitute this region. The region is about 50 to 100  m above the sea level. This region is believed to be created from the soil from the Deccan plateau. The area is formed by the silt brought by the tributaries of Bhagirathi, Mayurakshi River, Ajay River, Damodar and Rupnarayan River which flow over the western plateau region made up of laterite soil make the soil of the area red in colour. The land slope is from west to the south-east and formation of  natural levees along the river banks is a common phenomenon. Coastal plain. A small coastal region is on the extreme south of the state. A part of the district of Purba Medinipur along the Bay of Bengal constitutes the coastal plain. This emergent coastal plain is made up of sand and mud deposited by rivers and by wind. Parallel to the coast are colonies of sand dunes and marshy areas. The Digha dune lies nearest to the Bay of Bengal while the Kanthi dune is the farthest from it. In some areas dunes occur at a distance of 15–16 km  from the coast and are 11–12 m high. Sunderbans. The Sundarbans delta is the largest mangrove forest in the world situated in the South 24 Parganas district. It lies at the mouth of the Ganges and is spread across areas of Bangladesh and West Bengal, India. The Bangladeshi and Indian portions of the jungle are listed in the UNESCO world heritage list separately as the Sundarbans and Sundarbans National Park respectively, though they are parts of the same forest. The Sundarbans are intersected by a complex network of tidal waterways, mudflats and small islands of salt-tolerant mangrove forests, and  presents an excellent example of ongoing ecological processes. The general average height of the area is 10 m. This area has been created by deposition of silt by its numerous rivers namely, Hoogly, Matla River, Jamira River, Gosaba River, Saptamukhi River, Haribhanga River and their tributaries. The formation of the delta is an ongoing process and new bars and islands are being created along the rivers and at the river mouth. A large section of the area remains under water during incoming times. The area is known for its wide range of fauna. The most famous among these is the  royal Bengal tiger, but numerous species of birds, spotted deer, crocodiles and snakes also inhabit it. It is estimated that there are now 400 Bengal tigers and about 30,000 spotted deer in the area. Western plateau and high lands. The Western plateau and highlands forms the eastern fringes of the Chota Nagpur Plateau and is made up of igneous rocks of the Archaean era as well as coal-bearing mudstone and quartzite rocks of Carboniferous period. The western part of Purulia, Bankura, Birbhum, Bardhaman and Paschim Medinipur district constitutes this area. Because of long and continuous erosion, the whole region  has been transformed into an undulating peneplain. This area is interspersed by small monadnocks locally known as tila. Some of the important hills in the area include Ajodhya Hills (677 m), Panchet (643 m) and Baghmundi of Purulia, Biharinath (452 m) and Susunia (442 m) of Bankura. The area has a slope from the west to the east. The altitude in the area ranges from 500 to 100 m. Gorgaburu in the Ayodhya Hills (677 m) is the highest point in the region. Badland Topography Ganges delta. The Ganges delta consists of the whole of Nadia, Kolkata, North 24 Parganas , and South 24 Parganas districts and the Eastern half of Murshidabad district. River Ganges passes through this vast area and divides into three distinct parts – the old delta, the mature delta and the active delta. The old delta consists of the districts of Murshidabad and Nadia. The formation of delta is complete and the rivers here are heavily silted and many have even dried up in due course of time. Silted rivers, swamps, beels and oxbow lakes forms the area. This area is also known as Bagri region. The districts of Kolkata and North 24 Parganas form mature delta region . The rivers are slow and meandering and frequently shift their courses. Swamps, beels and oxbow lakes characterises the scenery. The district of South 24 Parganas is known to be the active delta of the Ganges, where the formation of delta is still an ongoing process. Agro-climatic groups. Depending on soil and climate variations, West Bengal can be divided into six broad divisions: River. Ganges enters West Bengal near Rajmahal and then flows in a south-easterly direction. It divides into two near north of Dhulian in Murshidabad district. One branch enters Bangladesh as the "Padma" or "Pôdda", while the  other flows through West Bengal as the Bhagirathi and Hooghly River in a southern direction. The Bhagirathi-Hoogly is the main river in West Bengal which flows past some of the important cities like Murshidabad, Baharampur, Nabadwip, Chinsura, Chandannagar, Srirampur, Howrah, Kolkata, Diamond Harbour and Haldia. It empties its water into Bay of Bengal near Sagar Island in the South 24 Parganas. The Mayurakshi, Ajay, Damodar, Kangsabati, Rupnarayan and their tributaries which rise in the Western plateau and high lands flow eastwards through the different districts of West Bengal and joins the Bhagirathi on the right bank. The Mayurakshi, which  is fed by tributaries Brahmani, Dwarka, Bakreshwar and Kopai joins the Bhagirathi near Kandi, Murshidabad, the Ajay, which rises in the hills of Bihar, joined by the Kunur, flows down the plateau fringe, marking the boundary between Bardhaman and Birbhum districts joins it near Katwa and Damodar, with its small meandering distributaries, small streams, Khari, Banka and Behula joins the Bhagirathi near Uluberia. The Damodar is known as the sorrow of Bengal, is now controlled by making the Damodar Valley Project. The Dwarakeswar and Shilabati rivers join to form Rupnarayan and the Kangsabati and Keleghai rivers join to form the  Haldi. The Rupnarayan and Haldi fall into the Bhagirathi in the East Midnapure district. The Subarnarekha River after flowing for a short distance in West Bengal reenters into Orissa. These rivers carry with them plenty of water thus keeping the Bhagirathi river submerged with water throughout the year. The rivers along with water carry silt and sand eroded from the western plateaus and deposits them in the Bhagirathi and the rivers themselves. This silting is causing great inconvenience for the Kolkata Port and often result flooding in the years of heavy rain. The distributaries of the Padma River like Bhairab , Jalangi, Mathabhanga River and their tributaries enters West Bengal and joins the Bhagirathi on its left bank. The Bhairab and the Jalangi meet and their joined waters known as Jalangi falls into Bhagirathi. The Mathabhanga divides into branches namely; Churni and Ichhamati, while the Churni meets the Bhagirathi while the other flows southwards and joins the Kalindi. The Sunderbans region is covered by numerous estuaries and streams, mainly distributaries of main rivers. The rivers are interconnected and are fed by tidal waters. The major rivers of the area are Hoogly, Matla, Gosaba, Saptamukhi, Haribhanga, Piyali, Thakuran/ Jamira, Raimangal, Kalindi and  Ichhamati. The Teesta flows cutting deep gorges from north to south in the mountainous Darjeeling district, it enters the plains at Sevoke and flows in a mighty stream on straight line towards the south east until it pours its waters into the Brahmaputra in Bangladesh. Torsa, Jaldhaka, Kaljani, Raidak, Sankosh and Mahananda rivers are in the northern hilly region which rise in the Himalayas and flow in a southerly direction through the districts of Darjeeling, Alipurduar, Jalpaiguri, Cooch Behar and North and South Dinajpur and enters Bangladesh. As most of the rivers are snow fed, so most of the rivers  are perennial in nature and often floods during the rainy season. The entire region is made up of sand, gravel and pebbles laid down by these rivers. The Mahananda rises from the Dow Hills forest, near the town of Darjeeling and are fed by similar small rivers like, Mahananda, Balason, and Machi and runs in a zig-zag way through the district of Malda and joins the Padma in Bangladesh. In the central region, the main river is the Mahananda. The Tangon and Punarbhabha, and Atrai arises in the plains, while the former two joins and flows into Mahanadi, Atrai  flows into the Padma. Wetlands. The Sundarbans delta is the largest mangrove forest in the world. It lies at the mouth of the Ganges and is spread across areas of Bangladesh and West Bengal, India. The Bangladeshi and Indian portions of the jungle are listed in the UNESCO world heritage list separately as the Sundarbans and Sundarbans National Park respectively, though they are parts of the same forest. The Sundarbans are intersected by a complex network of tidal waterways, mudflats and small islands of salt-tolerant mangrove forests, and presents an excellent example of ongoing ecological processes. The area is  known for its wide range of fauna. The most famous among these is the Bengal tiger, but numerous species of birds, spotted deer, crocodiles and snakes also inhabit it. It is estimated that there are now 400 Bengal tigers and about 30,000 spotted deer in the area. Climate. West Bengal's climate varies from tropical savannah in the southern portions to humid subtropical in the north. The main seasons are summer, rainy season, a short autumn, and winter. While the summer in the delta region is noted for excessive humidity, the western highlands experience a dry summer like northern India , with the highest day temperature ranging from to . At nights, a cool southerly breeze carries moisture from the Bay of Bengal. In early summer brief squalls and thunderstorms known as "kal-baisakhi" often arrive from the north or northwest. Monsoons bring rain to the whole state from June to September. West Bengal receives the Bay of Bengal branch of the Indian Ocean monsoon that moves in a northwest direction. Winter (December–January) is mild over the plains with average minimum temperatures of . A cold and dry northern wind blows in the winter, substantially lowering the humidity level. However, the Darjeeling  Himalayan Hill region experiences a harsh winter, with occasional snowfall at places. Natural resources. West Bengal stands third in the country in terms of mineral production. The state contributes about one-fifth to the total production of minerals in the country. Coal constitutes 99% of the minerals extracted in West Bengal; fireclay, china clay, limestone, copper, iron, wolfram, manganese and dolomite are mined in small quantities. There are good possibilities of obtaining mineral oil and natural gas in the areas near the Bay of Bengal, in Purba Medinipur, Sundarbans, South 24 Parganas and North Bengal plains. Research is ongoing in  various places to locate natural gas. West Bengal is the third largest state for coal production, accounting for about half of India's total. Coal is extracted from about 228 mines in the Raniganj and Asansol region of Bardhaman district. High grade bituminous coal is mined at Raniganj, Dishergarh, Santaldih, Kulti, Barakar, Ghushik, Kajora. Coalfields stretch over an area of about . The coalfields of Raniganj support the Asansol-Durgapur industrial belt by providing fuel to the industries as well as generation of thermal power. Lignite mined in Darjeeling is used to make briquettes. Coal deposits are also found along the  Ajoy river in Birbhum district. West Bengal ranks next to Bihar and Madhya Pradesh in production of fireclay. Most of this mineral is extracted in the Raniganj region along with a small quantity also extracted from Birbhum and Purulia. China clay used in the pottery, paper, textile, rubber and paint industries is unearthed at Mohammad Bazar in Birbhum and Mejia in Bankura. The rest of the production comes from Purulia, Bardhaman, Darjeeling and Jalpaiguri. In 1993–94 1.24 lakh metric tons of fireclay were produced in West Bengal. Limestone which is used in cement industry is mined in Bankura, Purulia, Darjeeling  and Jalpaiguri. There are copper mines in Jalpaiguri and Darjeeling. Small quantities of low quality iron-ore are mined in Bardhaman, Purulia, Birbhum and Darjeeling. There is manganese in the Jhargram region of Paschim Medinipur, Purulia and Bardhaman. Wolfram is mined at Jhilimili in Bankura. The state's production of dolomite comes from the Dooars region of Jalpaiguri. 38.5 thousand tonnes of dolomite were raised in 1993–94.