Flooding In Bangladesh:
Bangladesh is located in the South of Asia, It is surrounded by India and at the southern border there is Myanmar and the Bay of Benegal. It is one of the worl's poorest countries and is very densley populated with the population of 140million living mainly on flood plains of the river Ganges, Brahmaputra and Meghna. These three rivers have deposited tons of silt over thousands of years, creating one of the most fertile areas in the world.
Bangladesh is affecdted by both river and coastal flooding. River floods occur every year and are part of the cycle of snow-melt and monsoon rainfall. In some years the monsoon are particularly heavy or prolonged which is often the cause of extreme flood events. Coastal flooding is created by cyclones that build up in the Indian Ocean and move towards the Bay of Benegal. Water is funneled towards Bangladesh meaning as storm surge - extreme storm waves created by strong winds and low pressure, leading to higher sea levels and flooding - that may reach 6m high flooding large areas of land. When combined with heavy rainfall and river flooding, the effects of cyclones can be totally devastating.
Factors that increase the flood risk:
- Trees cleared for fuel and grazing, increased surface runoff
- Heavy monsoon rainfall causes summer flooding
- Melting of snow from the Himalayas adds to the volume of water in warmer months
- Defoestation in the Himalayas increases surface runoff
- Increased surface runoff leads to soil erosion and more silt, raising the river beds. The bed of Brahmaputra is rising 5cm/year
- 70% of total land area is less than 1m above sea level meaning there is nowhere for water to drain to
- Rapid unplanned growth has added to the problem of flooding. Urban Populations in Bangladesh have increased from 4% in 1951 to 35% in 2009. The growth is largely made up of poor migrants who often live in vulnerable areas.
- Cyclones create a storm surge
- Silt blocks river channels and creates islands, reducing the carryine capacity of rivers.
- Meeting of the three huge rivers increades the flood risk
- Bangladesh is 80% floodplain amd delta, making it susceptible to flooding.
- In India the…