In addition to the direct effects of climate change induced sea level rise, it is important to be aware of the effect of salt infiltration on farming. Much of the world’s cropland is near the coast and at low altitude. It is therefore vulnerable to being rendered infertile by salt from the oceans, as increased sea levels produce brackish rivers and more extreme storm surges. Many of these croplands are in developing countries, where the compounded effects of climate change are most likely to overwhelm domestic adaptation capacity.
Scientists have predicted that a 90cm increase in sea level would cause major infiltration problems in Bangladesh. Most recent scientific evidence suggests a sea level rise of about 1m by 2100, and possibly significantly more.
Seas ‘threaten 20m in Bangladesh’
By David Shukman
BBC News, Bangladesh
Up to 20 million people in low-lying Bangladesh are at risk from rising sea levels in the coming decades, according to new research.
Scientists predict that salty water could reach far inland, making it hard to cultivate staple foods like rice.
The research comes as the government appeals for $5bn (£3bn) over five years to combat climate change.
In May, Cyclone Aila left thousands homeless, killed many and caused widespread flooding and damage.
The predictions come from the Centre for Environmental and Geographic Information Services (Cegis) in Bangladesh.
It suggests a surprisingly small area of land will be permanently lost to the waters, but notes that vast tracts in the south-west could be inundated every monsoon season.
Rising Seas Are Flooding Bangladeshi Farms With Salt Water
The slow but ongoing process is disrupting the local economy.
Shondha Rnai’s small island paradise in the Bay of Bengal is threatened by salt. The little fresh water she needs is taken up by shrimp cultivation for the U.S. and Europe.
She’s one of roughly 8 million people living on artificial islands built by the Bangladeshi government in the 1960s to create 1.2 million hectares of farmland to feed its growing population.
Known by the Dutch term polder, these 139 islands surrounded by dikes are now under assault by rising seas, sinking land, a strained supply of river water, and a radical shift in farming practices: from land-based agriculture to shrimp cultivation.