Bangladesh expands despite global warming
New data suggests that Bangladesh is getting bigger - in contrast to earlier predictions that much of the low-lying nation would sink because of rising sea levels due to climate change.
According to specialists, more than 1 billion metric tonnes (MT) of sediment travels down the Ganges, Brahmaputra and Meghna rivers to the Bay of Bengal annually, much of which comes to rest along the southern shoreline.
Known as 'accretion', the process has been going on for decades and is already having an impact.
Using satellite imagery, scientists at the Dhaka-based Centre for Environmental and Geographic Information Services (CEGIS) a government-owned research organisation, now say the country is growing by 20 sqkm annually.
In the 1950s, Bangladesh (then East Pakistan) was 147,000 sqkm in size. Today it is 148,393 sqkm - growing at a rate of 232 sqkm every 10 years.
But the news also raises many questions, particularly as others have predicted that Asia's most densely populated nation was on the verge of sinking.
According to the UN Intergovernmental Panel on Climate Change (IPCC), by 2050, nearly one-fifth of Bangladesh's land mass would be under water, 20 million Bangladeshis would become environmental refugees and the country would lose 30 percent of its food production.
James Hansen, director of the NASA Goddard Institute for Space Studies, went so far as to predict that with a 25m rise in sea levels, the entire country could well sink by 2100.
'Bangladesh will suffer the consequences of the greenhouse effect and climate change even if the emergence of new lands off its coast continues,' Reazuddin Ahmed, director of the Department of Environment (DoE), said.
'If global warming causes the predicted sea rise to happen, it will far exceed the rate of sedimentation in the Bay of Bengal, and the inundation will occur,' he said.
CEGIS based its results on more than 30 years of satellite imagery of the coastal area.
'We compared the satellite images of 1973 with those of now, and saw that there has been accretion of nearly 1,000 sqkm of new land in the Bay of Bengal where all three major rivers of Bangladesh meet with the sea and deposit the silt that they carry from upstream,' confirmed Maminul Haque Sarker, head of CEGIS. [See satellite images]
'If these deposits of silt at the mouth of the rivers continue we might get another 1,000 sqkm of new land in the next 50 years,' Sarker said.
'Natural accretion has been going on here for hundreds of years along the estuaries and all our models show it will go on for decades or centuries into the future,' said Mahfuzur Rahman, head of Bangladesh Water Development Board's Coastal Study and Survey Department.
'Natural accretion due to sedimentation more than compensates for the loss of land caused by river bank erosion,' he added.
In the 1950s and 1960s the government built scores of dykes and polders to prevent floods and the intrusion of saline water in the southern part of the country.
Rahman is convinced that by building more dams and polders Bangladesh would be able to help create 4,000-5,000 sqkm of new land in the near future.
Bangladesh - one of the lowest producers of greenhouse gas - is expected to ask for billions of dollars to fight the effects of climate change at a conference of international donors scheduled for 10 September in London.
According to the World Bank, the goal of the conference is to highlight that Bangladesh is already living with climate change and why tackling the issue is critical to sustain progress made towards achieving the country's Millennium Development Goals. The conference will also highlight the need for an agreement on global emissions reduction, the bank said.