Kolkata is located in the eastern part of India. It has spread linearly along the banks of the Hooghly River. The Kolkata Municipal Corporation has an area of 205 square kilometres.[1] The city is near sea level, with the average elevation being 17 feet.[2] The whole area is in the Ganges Delta which starts within 100 km south of the city. Most of the city was originally marshywetlands, remnants of which can still be found especially towards the eastern parts of the city.
Geology
Indo-Gangetic Plain, the soil and water are predominantly alluvial in origin. Kolkata is located over the "Bengal basin", a pericratonic tertiary basin.[3] Bengal basin comprises three structural units: shelf or platform in the west; central hinge or shelf/slope break; and deep basinal part in the east and southeast. Kolkata is located atop the western part of the hinge zone which is about 25 km (16 mi) wide at a depth of about 45,000 m (148,000 ft) below the surface.[3] The shelf and hinge zones have many faults, among them some are active. The total thickness of sediment below the Kolkata is nearly 7,500 m (24,600 ft) above the crystalline basement; of
these the top 350–450 m (1,150–1,480 ft) is quaternary, followed by 4,500–5,500 m (14,760–18,040 ft) of tertiary sediments, 500–700 m (1,640–2,300 ft) trap wash of cretaceous trap and 600–800 m (1,970–2,620 ft) permian-carboniferousGondwana rocks.[3] The quaternary sediments consist of clay, silt, and several grades of sand and gravel. These sediments are sandwiched between two clay beds: the lower one at a depth of 250–650 m (820–2,130 ft); the upper one 10–40 m (30–130 ft) in thickness.[4] According to the Bureau of Indian Standards, on a scale ranging from I to V in order of increasing susceptibility to earthquakes, the city lies inside seismic zone III.[5]
City geography
Spread roughly north–south along the east bank of the Hooghly River, Kolkata sits within the lower Ganges Delta of eastern India; the city's elevation is 1.5–9 m (5–30 ft).[6] The city is fringed by extensive mangrove ecosystems and tidal flats.[7]
The urban agglomeration encompassed 72 cities and 527 towns and villages, as of 2006[update].[9] Suburban areas in the Kolkata metropolitan area incorporate parts of the following districts: Kolkata, North 24 Parganas, South 24 Parganas, Howrah, Hooghly and Nadia.[10]: 15 Kolkata, which is under the jurisdiction of the Kolkata Municipal Corporation (KMC), has an area of 205 km2 (79 sq mi).[11] The east–west dimension of the city is comparatively narrow, stretching from the Hooghly River in the west to roughly the Eastern Metropolitan Bypass in the east—a span of 9–10 km (5.6–6.2 mi).[12] The north–south distance is greater, and its axis is used to section the city into North, Central and South Kolkata. East Kolkata is also a section.
East Kolkata is largely composed of newly developed areas like Topsia, Picnic Garden, Tangra, Gobra, Kustia, Tiljala, Anandapur, East Kolkata Twp, Panchasayar, Madurdaha, Nayabad, Kalikapur, Purbalok, Mukundapur, Ajoy Nagar, Hiland Park, Chak Garia, Patuli, Budherhat, Nayabad and New Garia. Outlying developing areas include Dhapa, Uttar Panchannagram, Chowbaga, Bantala and VIP Nagar. In the pace of rapid urbanization and growing demand for housing and commercial spaces, the New Town, Kolkata was created on the eastern outskirts of Kolkata to serve the dual purpose of establishing a new business centre to reduce the mounting pressure on the existing Central Business Districts (CBD) and increasing housing stock supply by creating new residential units.
Howrah and Hooghly (Urban)
Technically Howrah and the urban part of Hooghly all have individual identities alongside they are the part of Kolkata Metropolis. Likewise Howrah city is a twin city of Kolkata city. Nabanna, Santragachi, Belur, Bally, Uttarpara, Konnogar, Rishra, Serampore, Bhadeswar, Chinsurah, Hooghly, Chandannagor and Bandel all cities under Kolkata Metropolitan Area, having their fragrance of history, culture. This area is called "Little Europe Of India". All areas are well connected with the city centre.
Kolkata has a Tropical wet-and-dry climate, with summer monsoons. The annual mean temperature is 29.2 °C (84.6 °F); monthly mean temperatures range from 19 to 30 °C (66 to 86 °F) and maximum temperatures can often exceed 45 °C (113 °F) during May–June. Winter tends to last from December to early-February, with the lowest temperatures hovering in the 12 °C — 14 °C range during December and January. The highest recorded temperature is 43 °C (109 °F) and the lowest is 5 °C (41 °F).[20]
Monsoon is the most notable phenomenon in the climate of the city. Maximum rainfall occurs during the monsoon in August (306 mm) and the average annual total is 1,582 mm. Early morning mists and evening smog occur often due to temperature inversions. Summer is dominated by strong southwesterly monsoon winds. The city's total duration of sunshine is 2,528 hours per annum, with the maximum insolation occurring in March.[21] Often during early summer, spells of thunderstorms and heavy rains lash the city, bringing some relief from the heat and intolerable humidity. These thunderstorms are locally known as Kalbaishakhi (Nor-wester). According to a United Nations Development Programme report, its wind and cyclone zone is a "very high damage risk".[5]
^"Introducing KMA"(PDF). Annual Report 2011. Kolkata Metropolitan Development Authority. 2011. Archived from the original on 5 June 2013. Retrieved 9 February 2012.{{cite web}}: CS1 maint: unfit URL (link)
^"007 Kolkata (India)"(PDF). World Association of the Major Metropolises. Archived from the original(PDF) on 8 March 2012. Retrieved 31 August 2007.
^Sahdev, Shashi; Verma, Nilima, eds. (2008). "Urban Land price Scenario- Kolkata − 2008". Kolkata—an outline. Industry and Economic Planning. Town and Country Planning Organisation, Ministry of Urban Development, Government of India. Archived from the original(DOC) on 26 April 2012. Retrieved 20 November 2012.
^Sahdev, Shashi; Verma, Nilima, eds. (2008). "Urban Land price Scenario- Kolkata − 2008"(DOC). Trends in land prices in Kolkata. Industry and Economic Planning. Town and Country Planning Organisation, Ministry of Urban Development, Government of India.
^Yardley, Jim (27 January 2011). "In city's teeming heart, a place to gaze and graze". The New York Times. New York. Archived from the original on 6 March 2014. Retrieved 27 November 2011. To Kolkata, it is the 'lungs of the city,' a recharge zone for the soul.
^Das, Soumitra (21 February 2010). "Maidan marauders". The Telegraph. Kolkata. Archived from the original on 18 January 2012. Retrieved 27 November 2011.
^Chakravorty, Sanjoy (2000). "From colonial city to global city? The far-from-complete spatial transformation of Calcutta". In Marcuse, Peter; Kempen, Ronald van (eds.). Globalizing cities: a new spatial order?. Oxford, UK: Blackwell Publishing. pp. 56–77. ISBN978-0-631-21290-4.