The discrepancies are much bigger in certain regions, like Southeast Asia and Pacific nations, where ocean dynamics are more complex. There, coastal sea levels are up to several meters higher than commonly estimated.
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From a global perspective, the findings indicate that hundreds of millions more people — particularly in Vietnam, the Philippines, Indonesia, the Maldives and other Southeast Asian and Pacific nations — are living closer to sea level than widely assumed by Western experts and policymakers.
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It’s hard to imagine not being able to trust a map in an age where GPS and satellite imagery is so prevalent. But the new study has identified a far-reaching problem in the method that researchers often use to understand coastlines and how they might change in a warming climate.
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In the simplest of terms, they were underestimating where coastal sea levels already are.