Sea levels are likely to rise faster than previously thought, meaning low-lying coastal cities in the US could be flooded much more frequently in the coming decades, a NASA study has found.
According to the study, which analyzed three decades of satellite observations, sea levels along the coasts of the contiguous United States could rise by as much as 30 centimeters above the current waterline by 2050, the research team said said in a statement (opens in new tab). The Gulf Coast and Southeast are expected to be hardest hit and likely to experience increased storm and tidal flooding in the near future, according to the study, published Oct. 14. 6 in the diary Communication Earth & Environment (opens in new tab).
The results support the “higher-quality” scenarios set out in the multi-agency in February Technical report on sea level rise (opens in new tab). The report suggested that “significant sea level rise” could hit US coasts over the next 30 years, and projected an average rise of 10 to 14 inches (25 to 35 cm) for the east coast; 35 to 45 cm (14 to 18 in) for the Gulf Coast; and 4 to 8 inches (10 to 20 cm) for the west coast.”
NASA’s study built on methods used in the earlier interagency report and was led by a team of researchers and scientists based at NASA Jet Propulsion Laboratory (opens in new tab) in California, dedicated to both exploring the deepest corners of space and using satellites to improve the “understanding” of the earth.
The NASA research used satellite altimeter measurements of sea surface height and then correlated them with it National Oceanic and Atmospheric Administration (opens in new tab) (NOAA) Tide gauge records going back over 100 years. As a result, NASA can confidently say that its satellite measurements are not anomalous and are fully supported by field results.
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While the results of the new study are undoubtedly cause for concern, Jonathan Overpeck (opens in new tab)an interdisciplinary climate scientist at the University of Michigan who was not involved in the research suggested that the projections were by no means out of the blue.
“NASA’s findings appear robust and unsurprising. We know sea level rise is accelerating, and we know why,” he told Live Science in an email. “More and more polar ice is melting, in addition to the oceans expanding as they warm. Clearly, sea level rise will get worse as long as we let it climate change continue.”
This point of view is shared by David Holland (opens in new tab)Physical climate scientist and professor of mathematics at New York University, who was not involved in the study. “The quality of the satellite data is excellent and therefore the results are reliable,” Holland told Live Science in an email. “The study shows that the global ocean is rising, and what’s more, the rise is accelerating. The projected increase for the Gulf Coast of about 1 foot by 2050 is huge hurricane-related storm surges even worse than at present.”
Other factors may also contribute to sea level rise along the US coastline. The study showed that the problems related to sea level rise “could be exacerbated by natural fluctuations”. Earth‘, such as the effects of El Niño and La Niña through the mid-2030s, with each U.S. coast projected to ‘experience intensified flooding due to an ocean shake moonwhich occurs every 18.6 years,” the statement said.
The effects of El Niño — the warming of surface temperatures in the Pacific Ocean near South America, which can lead to increased precipitation — and La Niña — the cooling of the surface waters of the Pacific oceans — can make accurately predicting sea-level rise a challenge, and may falsify the measured values. Ben Hamlington, head of NASA’s Sea Level Change Team, noted that natural events and phenomena must always be accounted for, and said all predictions will inevitably be refined as satellites collect data over time.
Despite the study’s dismal findings, some experts hope that impactful, high-quality research like this will compel decision-makers to focus on tackling the ongoing climate crisis and encourage the public to call for effective measures to be put in place.
“It’s impossible to ignore. I think so [increased flooding] catalyzes action as many coastal communities discuss these issues and how they are responding to them,” he said Robert Nichols (opens in new tab), director of the Tyndall Center for Climate Change Research in the UK, who was not involved in the study. “We have the means to deal with this mitigation challenge to stabilize the global one temperatures and slow – but not entirely halted – sea level rise, which unfortunately will continue for centuries to come warm up we’ve seen that before.”
Ultimately, humanity will have to adapt as climate change alters our planet’s oceans and seas.
“This could involve withdrawal in some places, raising land in other places and defense elsewhere,” Nicholls told Live Science. “There is no one-size-fits-all solution. If we take this path, the future is manageable. Likewise, if governments and society ignore these issues, the future will be one of real chaos.”
