“a new study, published Wednesday in the journal Nature, has found that the vast majority of scientific studies that calculate coastal sea level have underestimated how high the water already is”
“Coastal sea levels are, on average, eight inches to a foot higher than these scientific studies and maps indicate worldwide, the research found”
“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”
“The problem starts with a decades-old method that compares satellite-based measurements of land elevation to something scientists know as a “geoid model,” which is a technique for estimating mean sea level based on Earth’s gravitational field. This method was once considered “state-of-the-art,” Dr. Minderhoud said, and was commonly taught in graduate school”
“But other satellites and instruments can measure real sea level and reveal local differences from factors like currents, winds and tides, which can also influence sea levels but are not included in the gravitational-field model. Scientists can most accurately estimate sea level when both pieces of the puzzle are combined correctly”
“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”