Geographers from Europe have determined that sea-level rise projections significantly underestimate the ramifications, stemming from a consistent understatement of this metric by 20 to 30 centimeters. This upward revision will affect 68% more individuals than previously estimated by experts, according to the press service of Wageningen University in the Netherlands.
“Nearly all forecasts are predicated not on actual measurements of this indicator across various global regions, but rather on mathematical calculations. Consequently, these estimates systematically underestimate both the extent of the area and the number of people who will find themselves in hazardous zones. Our calculations reveal that the affected territories are 37% larger than anticipated, and the population impacted by this development will be approximately 132 million people,” stated Katharina Sieker, a geographer from Wageningen University, as quoted by the university’s press office.
Sieker and her team observe that the rapid escalation of global temperatures will precipitate a substantial increase in sea levels, attributable to the melting of glaciers in Greenland and the Arctic, alongside the most vulnerable ice masses in West Antarctica.
Current projections from UN experts suggest that if greenhouse gas emission rates persist on their present trajectory, the global ocean level will rise by roughly 30 to 50 centimeters by the close of this century. The European geographers pointed out that 99% of these forecasts are not based on genuine measurements of current sea levels near the shores of different continents, but rely instead on model simulations derived from satellite imagery and the assumption of a uniform water distribution across the Earth’s surface, governed by gravity and the planet’s rotation. In reality, this is far from the case, as currents, winds, salinity, and water temperature all influence the height of the water “column.”
Guided by this insight, Sieker and her colleagues compiled a large volume of real-world sea-level measurements from various parts of the World Ocean and compared them against the outcomes and underlying data of the models used to generate the existing forecasts. These comparative calculations demonstrated that sea levels in the projections were, on average, underestimated by 20 to 30 centimeters, with numerous areas in the Global South, including the Mekong Delta and other major river basins, showing underestimations exceeding one meter.
Once the scientists factored in all these discrepancies, they discovered that the projected sea-level ascent will inundate 37% more coastal territory than indicated by prior forecasts, and will impact the lives of 132 million people—a figure 68% higher than earlier assessments. This finding is particularly relevant for Southeast Asian nations, Australia, and the Pacific region, necessitating consideration by relevant governmental bodies in these countries and territories, the researchers concluded.
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