GEOGRAPHY

The state is wedged between the Lakshadweep Sea and the Western Ghats. Lying between northern latitudes 8°18' and 12°48' and eastern longitudes 74°52' and 77°22',[99] Kerala experiences the humid equatorial tropic climate. The state has a coast of 590 km (370 mi)[100] and the width of the state varies between 11 and 121 kilometres (7 and 75 mi).[101] Geographically, Kerala can be divided into three climatically distinct regions: the eastern highlands; rugged and cool mountainous terrain, the central mid-lands; rolling hills, and the western lowlands; coastal plains.[102] Pre-Cambrian and Pleistocene geological formations compose the bulk of Kerala's terrain.[103][104] A catastrophic flood in Kerala in 1341 CE drastically modified its terrain and consequently affected its history; it also created a natural harbour for spice transport.[105] The eastern region of Kerala consists of high mountains, gorges and deep-cut valleys immediately west of the Western Ghats' rain shadow.[102] 41 of Kerala's west-flowing rivers,[106] and 3 of its east-flowing ones originate in this region.[107][108] The Western Ghats form a wall of mountains interrupted only near Palakkad; hence also known Palghat, where the Palakkad Gap breaks.[109] The Western Ghats rise on average to 1,500 metres (4,900 ft) above sea level,[110] while the highest peaks reach around 2,500 metres (8,200 feet).[111] Anamudi, the highest peak in south India, is at an elevation of 2,695 m (8,842 ft).[112]

Kerala's western coastal belt is relatively flat compared to the eastern region,[113] and is criss-crossed by a network of interconnected brackish canals, lakes, estuaries,[114] and rivers known as the Kerala Backwaters.[115] The state's largest lake Vembanad, dominates the backwaters; it lies between Alappuzha and Kochi and is about 200 km2 (77 sq mi) in area.[116] Around eight percent of India's waterways are found in Kerala.[117] Kerala's 44 rivers include the Periyar; 244 kilometres (152 mi), Bharathapuzha; 209 kilometres (130 mi), Pamba; 176 kilometres (109 mi), Chaliyar; 169 kilometres (105 mi), Kadalundipuzha; 130 kilometres (81 mi), Chalakudipuzha; 130 kilometres (81 mi), Valapattanam; 129 kilometres (80 mi) and the Achankovil River; 128 kilometres (80 mi). The average length of the rivers is 64 kilometres (40 mi). Many of the rivers are small and entirely fed by monsoon rain.[118] As Kerala's rivers are small and lacking in delta, they are more prone to environmental effects. The rivers face problems such as sand mining and pollution.[119] The state experiences several natural hazards like landslides, floods and droughts. The state was also affected by the 2004 Indian Ocean Tsunami.