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Former President Donald Trump stands onstage Nov. 15, 2022, after announcing a third run for president at his Mar-a-Lago estate in Palm Beach, Fla. (AP) Former President Donald Trump stands onstage Nov. 15, 2022, after announcing a third run for president at his Mar-a-Lago estate in Palm Beach, Fla. (AP)

Former President Donald Trump stands onstage Nov. 15, 2022, after announcing a third run for president at his Mar-a-Lago estate in Palm Beach, Fla. (AP)

Tom Kertscher
By Tom Kertscher November 17, 2022

Trump vastly understates how much experts expect sea levels to rise

If Your Time is short

  • Experts predict rises in sea level many times larger than what Trump claimed.

  • The National Oceanic and Atmospheric Administration reported that U.S. sea level in 2100 is projected to be around 2 feet higher on average than it was in 2000, "if we are able to significantly reduce greenhouse gas emissions." 

  • The National Ocean Service predicted that sea level along the U.S. coastline is projected to rise, on average, 10 to 12 inches from 2020 to 2050.

Announcing his run to retake the White House, former President Donald Trump made a claim that seemed to ridicule expert projections about climate change.

Trump juxtaposed two global threats — nuclear war and rising sea levels — in his Nov. 15 announcement at his waterside Mar-a-Lago club and residence in Palm Beach, Florida.

"You cannot mention the nuclear word; it’s too devastating. The Green New Deal and the environment — which they say may affect us in 300 years — is all that is talked about. And yet nuclear weapons, which would destroy the world immediately, are never even discussed as a major threat. Can you imagine?" he said.

"They say the ocean will rise one-eighth of an inch over the next 200 to 300 years, but don't worry about nuclear weapons that can take out entire countries with one shot."

Trump’s quip got some laughter from the audience. But his dismissal of predictions for climate change-driven sea level rise is "so far from accurate as to appear to have been entirely fabricated," said Michael Oppenheimer, director of the Center for Policy Research on Energy and the Environment at Princeton University.

A Trump spokesperson did not respond to our emails.

Sea-level rise projections much higher than Trump’s claim

Trump made virtually the same claim as president during a 2019 rally. As our friends at FactCheck.org reported, the National Oceanic and Atmospheric Administration said then that global sea level was increasing by about one-eighth of an inch per year.

Reports issued in 2022 continue to dispel Trump’s claim:

  • NOAA reported that U.S. sea level in 2100 is projected to be around 2 feet higher on average than it was in 2000, "if we are able to significantly reduce greenhouse gas emissions." The estimate grows to 7.2 feet if on a "pathway with high greenhouse gas emissions and rapid ice sheet collapse."

  • The National Ocean Service, a part of the NOAA, predicted that sea level along the U.S. coastline is projected to rise, on average, 10 to 12 inches from 2020 to 2050 — as much as the rise that was measured from 1920 to 2020.

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Gary Griggs, an earth sciences professor at the University of California, Santa Cruz, said the state of California has advised coastal communities to plan for sea level increases of between 1 foot and 2½ feet by 2050.

Griggs also said that NOAA’s tide gauge for Palm Beach shows a rise of 0.15 inches per year.

Impact of rising sea levels

Almost 30% of the U.S. population lives in relatively high population-density coastal areas "where sea level plays a role in flooding, shoreline erosion and hazards from storms," according to NOAA. 

In coastal urban areas around the world, roads, bridges, subways, water supplies, oil and gas wells, power plants, and other infrastructure "are all at risk from sea level rise," the NOAA report said.

Global warming is causing the global mean sea level to rise, because glaciers and ice sheets worldwide are melting and adding water to the ocean, and the ocean’s volume is expanding as the water warms, the agency said.

The nonprofit Climate Central projected in September that in the U.S., property with an assessed value of at least $108 billion is at risk from rising seas by 2100.

Our ruling

Trump said, "They say the ocean will rise one-eighth of an inch over the next 200 to 300 years."

Experts predict rises in sea level many times larger than what Trump claimed. One federal agency said that U.S. sea level in 2100 is projected to be at least 2 feet higher on average than it was in 2000, and that’s with greenhouse gas emissions reduced "significantly."

Trump’s statement is false and ridiculous — Pants on Fire!

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Our Sources

C-SPAN, Donald Trump announcement excerpt, Nov. 15, 2022 

CNN, "Fact check: 20 false and misleading claims Trump made in his announcement speech," Nov. 16, 2022

FactCheck.org, "FactChecking Trump’s Presidential Bid Announcement," Nov. 16, 2022

FactCheck.org, "Trump Mocks Global Warming, Lowballs Sea Level Rise," Dec. 12, 2019

Washington Post Fact Checker, "New Trump campaign, same old falsehoods," Nov. 16, 2022

New York Times, "In Announcing 2024 Bid for Presidency, Trump Echoes Old Falsehoods," Nov. 16, 2022

National Ocean Service, "2022 Sea Level Rise Technical Report," February 2022

Climate.gov, "Climate Change: Global Sea Level," April 19, 2022

PolitiFact, "No, two photos don’t reveal sea levels, don’t prove climate change is a ‘hoax,’" April 21, 2021

PolitiFact, "Plymouth Rock pictures don’t prove sea levels are the same as 1620," July 20, 2022

Climate Central, "Sinking Tax Base: Land & Property at Risk from Rising Seas," Sept. 8, 2022

Email, Gary Griggs, sea level rise expert and distinguished professor of earth sciences, University of California, Santa Cruz, Nov. 17, 2022

Email, Michael Oppenheimer, sea-level expert, geosciences and international affairs professor, and director of the Center for Policy Research on Energy and the Environment at Princeton University, Nov. 17, 2022

California Ocean Protection Council, "State of California Sea-Level Rise Guidance, 2018 Update," accessed Nov. 17, 2022 

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Trump vastly understates how much experts expect sea levels to rise

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