New study claims rising sea levels far worse that previously calculated
A new research suggests that if carbon emissions peak by 2020, land now home to roughly a fifth of the populations of Bangladesh and Vietnam may be lower than high tide lines by 2100.
Quoting the research by Nature Communications, the World Economic Forum in an article said hundreds of millions more people are already at risk from climate breakdown-caused coastal flooding and sea level rise than previously thought.
The research also fears that the proportion under threat would rise to a third of the population in Bangladesh if emissions continue unchecked.
Even with immediate and deep emissions cuts, large swathes of the coastal land we live on now could be uninhabitable by the end of the century, the article said.
“Existing estimates of risk from sea-level rise – taken from NASA’s Shuttle Radar Topography Mission – did not exactly paint a rosy picture for coastal communities. But, in using space-based satellite imagery to measures the elevations of surfaces closest to the sky, much of the data actually reported the elevation of treetops and rooftops, rather than the ground itself.”
“As a result, it overestimates coastal elevations by more than two metres on average, and more than four metres in urban areas,” the article added.
Based on the new model, it has been estimated not 28 million but 110 million people already live below the current high tide line. At the same time, instead of 68 million people living below annual flood levels, the figure is now 250 million – the same number that live less than one metre above sea level.
Mentioning that the increase in vulnerability to sea-level rise and flooding is not evenly distributed, the report also said more than 70% of those living on at-risk land are in eight Asian countries: Bangladesh, India, Vietnam, Indonesia, Thailand, the Philippines, China, and Japan.
“And for many of these countries, the increase in risk that the new model predicts for the coming decades is much higher than three-fold.”
It also mentions that modern defences, such as levees and seawalls, will remain vital in protecting hundreds of millions of coastal residents, but these by no means guarantees protection against future sea levels and storms as superstorms already breach flood defences in the most developed cities in the world.
It also said that away from urban areas, the astronomical costs of protecting large areas from sea-level rise and flooding means that millions will need to be resettled in the coming decades – or else forcefully displaced by the rising seas.
“Even in countries such as the US and the UK, sea-level rise this century may require large-scale migration away from unprotected coastlines. In countries less able to cope, loss of lives and livelihoods, political chaos, and conflict are highly likely without support,” it said.