Climate-induced flooding is expected to imperil about 300 million worldwide
Coastal areas currently home to 42 million Bangladeshis will be vulnerable by 2050 to flooding made worse by climate change, no matter how aggressively humanity curbs carbon emissions, scientists have warned.
In the second half of the 21st century and beyond, however, choices made today will determine whether the global coastlines on maps today will remain recognizable to future generations, reported the journal Nature Communications.
Destructive storm surges fuelled by increasingly powerful cyclones and rising seas will hit Asia hardest, according to the study, reports AFP.
It is estimated that one-fourth of Bangladesh’s land will be reclaimed by sea, as per the study.
Bangladeshi environment and climate professionals agreed with the study as the knowledge of rising sea level is not new but reiterated the implifloocations of water salinity.
“Bangladesh will face major risk from rising sea level which may impact increase in water salinity. But, we should understand the research methodology. Climate Central did the report based on global context. Results may vary if research is conducted on one specific coastal area of Bangladesh,” said Prof Syed Hafizur Rahman, of Department of Environmental Science at Jahangirnagar University.
“Considering the history of thousands years of Bangladesh, and the local geo-math, it may not be possible to say such type of impact will hit the coastal areas or southern part of the country by 30 years of 50 years specifically,” he added.
“The weather patterns have been changing gradually, visible by the change in temperature. The significant rise in sea level could affect the coastal people. But we should not be nervous as we can still deposit sediments in the coastal areas,” said Prof Kazi Matin Uddin Ahmed, of Geology Department at Dhaka University.
In an article titled “The future of Bangladesh regarding climate change” published recently in a Bangladeshi magazine, the author Prof Md Khalequzzaman, of Geology Department of Lock Haven University Pennsylvania, analyzed that the coastal areas have been moving 80km towards the sea in Bangladesh over the last 200 years.
It is happening mainly in the south-eastern part of the country including Bhola, Noakhali and Barisal due to the alluvial sediments deposited by the rivers.
Therefore, Bangladesh is surviving against the rising sea level. But, due to continued water-logging in the coastal part, construction of dam to protect the area may increase salinity in fresh water in coastal areas.
Over two-third at risk in Asia
More than two-thirds of the populations at risk are in China, Bangladesh, India, Vietnam, Indonesia and Thailand, reports AFP.
In each of several dozen major cities – including Bangkok, Hong Kong, Shanghai, Taizhou, Surabaya, Dhaka, Mumbai, Ho Chi Minh City and Osaka – millions will find themselves in flood zones.
Using a form of artificial intelligence known as neural networks, the new research corrects ground elevation data that has up to now vastly underestimated the extent to which coastal zones are subject to flooding during high tide or major storms.
"Sea-level projections have not changed," said co-author Ben Strauss, chief scientist and CEO of Climate Central, a US-based non-profit research group.
"But when we use our new elevation data, we find far more people living in vulnerable areas than we previously understood," Strauss told AFP.
With the global population set to increase by two billion by 2050 and another billion by 2100 – mostly in coastal megacities – even greater numbers of people will be forced to adapt or move out of harm's way.