| Impact of rising sea level on Bangladesh Billy I Ahmed The World Bank reported in 2001 that the sea level is rising at the rate of about 3.0 mm a year in the Bay of Bengal. It warned of loss of Bengal tigers in the Sundarbans, world's largest mangrove forest, and threats to hundreds of bird species. fifteen to twenty per cent of Bangladesh is within one meter of the sea level. This means predicted sea level rise at a rate that is increasing will not only affect millions of people -- estimates at 13 to 30 million -- but will also flood out much rice production. The World Bank warned of a decline of rice crop up to 30 per cent with predicted sea level rise. This is not a one-time event that sometime in the future will affect so many. It is a constant process of ever higher tides which affects more and more people even in times of lower river flow and good weather. Sea levels are predicted to be rising twice as fast as was forecast by the United Nations, threatening hundreds of millions of people with catastrophe, scientists said recently in a dramatic new warning about climate change. Rapidly melting ice sheets in Greenland and Antarctica are likely to push up sea levels by a metre or more by 2100, swamping coastal cities and wiping out the living space of 600 million people who live in deltas, low-lying areas and small island states. Low-lying countries with increasing populations, such as in Bangladesh, Burma and Egypt, could see large parts of their surface areas vanish. Experts in Bangladesh estimate that a one-metre rise in sea levels would swamp 17 per cent of the country's land mass. The Pacific islands such as Tuvalu, where 12,000 people live just a few feet above sea level, and the Maldives would face complete destruction. Even Britain could face real challenges in lower-lying areas along the east coast, from Lincolnshire to the Thames estuary, with a much greater risk of disastrous "storm surges" such as the great flood of 1953 that killed 307 people. The waters created in the Himalayas flow out to east and west through the Ganges and Brahmaputra Rivers. The rivers meet to form the Meghna, which is second only to the Amazon, and then course south in hundreds of distributaries to form the largest delta on the planet. The floodplain of the Ganges and Meghna rivers makes the world's largest delta. Bangladesh is facing threat of global warming and the disaster unfolding for its impoverished population is all too obvious. The two rivers meander gently to the sea through the fertile green plain where the country grows most of its food. Soon it is all expected to disappear as rising seas leave vast areas of Bangladesh under water, wiping out much of the agriculture, displacing up to 30 million people and destroying species such as the Bengal tiger. The Sundarbans, situated in Bangladesh's south-western region, is one of the last untouched places on Earth and home to the largest population of tigers left in the wild. But the trees in the Sundarbans have suddenly started dying. And not just that: they have started dying in a way nobody has seen before, from the top-down. Nobody is sure what the cause is, but the country's leading scientists think the trees are dying because, in recent years, the water has turned from fresh to salty. The Sundarbans is a massive mangrove swamp, and the sea level has begun rising. What we are seeing may be one of the first casualties of rising sea levels caused by global warming. It is not just the Sundarbans that is already suffering the effects of rising salinity. Farmers in coastal areas who used to grow rice have switched to farming prawns, after the water in their paddy fields got too salty. This is the landscape of Bangladesh. The 140 million people share the same culture with Bengali Indians, Muslims and Buddhists, and to a lesser extent, with the hill people of Myanmar. This great delta is under constant change. Over time river channels are forming and eating away islands and sandbars depending on the amount of run-off, the rainfall of monsoon and cyclones, and the Bay of Bengal tides. Bangladesh is often battered by tropical cyclones and tornadoes, which funnel along its coast and then flood the low-lying delta. The country is well used to floods. But sea levels along the coast are rising fast - by three millimetres a year - as are water temperatures, making Bangladesh one of the most heavily populated areas in the world so vulnerable to the effects of climate change. Not quite like the Odyssian story, the Bangladeshis must look this Medusa in the face. Their fate is not being turned to stone but just the opposite -- seeing their lives washed away. The great cyclones (Southern Hemisphere hurricanes) of 1970 and 1991 taught many lessons to the government and the people. The people are resilient and used to the vagaries of river and weather. Still the population living along rivers on land less than a meter above high tide makes the issue crucial.. Retired national meteorologist M.H. Khan Chowdhury, citing the reports available, said, "On an average, river erosion takes away about (19,000 acres) of land every year. About one million people are directly or indirectly affected by river-bank erosion every year in Bangladesh." Tidal influence up the rivers extends to Dhaka, so even when river flow is normal the level of water follows the sea.For mile after mile the level of rice fields and buildings along the rivers are no more than a metre above high tide. Much shoreline is lower and filled with water during each high tide.. This is happening not at the height of monsoon when flooding is common, but at the end of the dry season. The writer is a tea planter, columnist and researcher http://www.thefinancialexpress-bd.com/2009/03/16/61312.html |
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