Where is the Gulf of Mannar?

The Gulf of Mannar lies between the south-eastern tip of India and the north-western coast of Sri Lanka.
Between India and Sri Lanka lies a chain of limestone islands covered with sand, as well as sand islands, stretching from India’s Pamban Island (also known as Rameshawaram island) to Sri Lanka’s Mannar island. This chain of islands is called Adam’s Bridge in English, Ātham Pālam in Tamil and Rama Sethu in Malayalam. The name Adam’s Bridge was given by a British mapmaker, and referred to legend that said that Adam (the first man in Christianity and Islam) crossed from India to Sri Lanka along this bridge to reach Adam’s Peak in the central part of Sri Lanka. The Indian name Rama Sethu refers to the Indian legend Ramayanaya: the bridge is supposed to have been built for the Indian Prince Rama to cross from India to Sri Lanka to rescue his wife Sita from Ravana, the king of Sri Lanka (http://en.wikipedia.org/wiki/Gulf_of_Mannar). Sethu means bridge.

Evidence from the past shows that Adam’s Bridge once connected India and Sri Lanka but now there is sea between the limestone and sand islands. The sea level in the past was much lower, therefore, there was a connection. Wave currents move the sand so that some sand islands disappear during certain parts of the year. According to historical records, people walked across Adam’s Bridge up until the 15th century, until a bad storm broke up the chain. However, even now much of Adam’s Bridge can be waded across.

Adam’s Bridge is 30 km long. The sea in this area is very shallow (1.5 to 3.5 m only), with sand shifting and resettling with wave currents.

Adam’s Bridge starts from Pamban island in Tamil Nadu, India (connected to the mainland by a man-made bridge) and ends at Mannar island in Sri Lanka. Mannar island is connected to the mainland by a causeway – which is a road raised over water with a few culverts underneath to allow some water to pass under.

To the northeast of Adam’s Bridge is the Palk Bay which leads to Palk Strait. Although they are narrow, ships can move pass through straits. Palk Strait is named after the British governor James Palk.
(http://en.wikipedia.org/wiki/Gulf_of_Mannar).

To the southwest of Adam’s Bridge is the Gulf of Mannar. The Gulf of Mannar is a shallow area of water connected to Lakshadweep Sea, which is part of the Indian Ocean in which the tip of India, Sri Lanka and the Maldives are found.

1.2 The climate in the Gulf of Mannar

The rainfall and the shape of the surface of the land dictate Sri Lanka’s climate.

In the centre of the island are high hills, surrounded by less high hills. Below this is the large area of mostly flat land.

Sri Lanka is a tropical island where the temperature does not vary much. However, rainfall varies greatly. The island receives its rain from two monsoons, the southwest and the northeast monsoon. The southwest monsoon comes from the direction of the Bay of Bengal, from May to September. The water vapour bearing winds cool as they rise above the central hills, and fall down as rain on the side of the hills that face the wind. During this period, the rest of the island remains more or less without rainfall.

Meanwhile, the northeast monsoon, blowing overland from India, snakes round the central hills to bring rain to the whole island from November to March. This means that the part of the island southwest of the hill is wet through most of the year, while the rest of the country has a dry spell. Because of this combination of both the shape of the surface of the land and rainfall, we are able to tell apart different climatic zones in the island. For the purpose of this module, we will use the Wet Zone, the Dry Zone, the Intermediate Zone and the Arid Zone. The Arid Zone receives only about 650 mm of rain every year, and suffers a long dry period for nearly three quarters of the year.

Much of the coastline near Mannar District lies in the Arid zone and the Dry Zone.


Climatic Zone Average Rainfall Remarks
Wet Zone 2,000 mm – 5, 000 mm The upcountry wet zone generally receives rain throughout the year. The low country wet zone is likely to have about 5 -6 months without rain.
Intermediate Zone 1,100 mm – 2,000 mm • The up country Intermediate Zone receives better rainfall than the rest of the Intermediate Zone.
• Some parts of the Mid Country Intermediate Zone may have about 6 months without rain.
• The Low Country Intermediate Zone may have about 6 months without rain.
Dry Zone 700 mm – 1,000 mm The Dry Zone receives rain only for about 3-4 months, mainly from the northeast monsoon. The rest of the year is dry.
Arid Zone About 650 mm The Arid Zone receives limited rain only for about three months. The lowest rainfall is in Hambantota. The rainfall in Mannar, Jaffna and parts of Kilinochchi district is also low (in the region of about 700 mm).