Aim to understand the impact of coastal flooding in Bangladesh.     

3 Great Rivers Ganges

Brahmaputra

Meghna

A history of flooding Major floods…. 1988 1998 2004 2007

Why? Use the clues around the room to explain 5 reasons why Bangladesh floods most years

Global warming is making sea levels rise, causing the land to retain the water for an abnormally long time. Bangladesh is getting closer and closer to sea level, because the sea level is rising, the water from the floods is no longer being quickly pulled down towards the ocean. Even if the flood is not that big, the water will remain for a period indefinitely longer than it would without global warming.

Deforestation Forests, soils, and water are being rapidly destroyed. The large population has caused depletion of all the forests, and farming on slopes has caused much soil erosion. There is not enough land in Bangladesh, farmers take whatever land they can get, including slopes. The soil that is being eroded then reduces the depths of the rivers, making them easily flooded. A thirty foot deep river can become twenty feet deep, and soon ten feet of water is being pushed over the banks of the river. If the population could be controlled, there would be less and less soil erosion, and therefore the floods could be slowly phased out.

Glacier Melt in the Himalayas Low lying land/delta Settlement built on floodplain

The Monsoon

Cyclone Sidr

http://www.youtube.com/watch?v=MAkz1AVZY_Y

June 2007 Heavy monsoon rains have caused devastation in Bangladesh. The port city of Chittagong has been particularly badly hit.

The city and surrounding areas have suffered both flooding and landslides.

Worst hit was a crowded shanty town near a military area.

The hillside collapsed, burying dozens of flimsy homes.

Officials said it may take till Tuesday for rescuers to recover the bodies of all the dead in Chittagong.

Correspondents say environmental experts have been warning that the risk of landslides has increased because of illegal clearing of hillsides for housing.

Fire officials said these were the worst ever rain-triggered landslides in Chittagong.

Positive impact of flooding: Regular annual flooding is essential to people who live on the flood plain of these rivers, the farming season is planned around the floods, rice is a main crop and requires large quantities of water. Also, when the river floods it leaves behind fertile silt.

Source: www.geographypages.co.uk BANGLADESH FLOODING Bangladesh is almost _____ % made up of river floodplains, and a large number of its 120 ________ population live in areas which are prone to flooding. There are 4 major rivers which meet in the country, the Ganges, Meghna, Jamuna and ______________.These are not only large rivers, but much of their channel lies in other countries such as _________, so Bangladesh is at the mercy of changes made upstream such as the large scale _______________ of wooded areas. Many people live on small temporary islands in the middle of the river channel called ________, which can disappear during a large flood. When a river floods, natural banks or ________ are created by large particles being deposited. There is a distinction to be made between flooding, which is the normal annual inundation of the _________, and floods which are abnormal conditions when the river level is much ________ than normal. This often occurs during the rainy season called the __________. People adapt by raising their houses up, and taking advantage of the good catches of _______ in the silt-laden waters of the delta. The principal crop is ________ which is ideal. WORDBANK Brahmaputra , Floodplain , Chars , Deforestation , Rice , Monsoon , higher , Levees , Prawns , 80 , Nepal , million Source: www.geographypages.co.uk