MAJURO - Rising sea levels are amplifying long-standing concerns about nuclear contamination in the Marshall Islands, prompting renewed appeals from local leaders for major emitting nations to do their part to address climate change.
The small independent Pacific state, consisting of 29 low-lying atolls and more than 1,000 islands, is among the most vulnerable countries in the world to rising seas.
Scientists predict that by 2100, sea levels could rise by about 2 meters, bringing longer periods of flooding and accelerating the erosion already reshaping the coastline.
The archipelago was the site of extensive Cold War nuclear testing carried out by the United States, leaving a legacy of nuclear contamination and questions over measures taken to safely dispose of and seal radioactive materials.
Those questions are now becoming concerns as sea levels are expected to soon engulf a concrete dome designed to contain the radioactive leftovers.
In the country's capital, Majuro, the effects of rising sea levels are visible daily. The main road west of the airport lies on a thin strip of land with ocean on either side, narrowing to around 15 meters at high tide. Seawater seeps through seawalls and washes onto the pavement, a routine inconvenience for residents.
"It's scary, of course, but there's nothing we can do," said Kamje Kaisha, a local carpenter.
Years of erosion have stripped away beaches that once served as natural buffers, leaving the roots of large trees exposed and destabilizing shoreline homes.
The land loss has also disrupted cultural practices. Marshallese families have traditionally buried their loved ones near the sea, reflecting a close relationship with the ocean.
But rising waters have submerged dozens of graves in recent decades, forcing some families to abandon tombs and relocate others further inland.
"We're a country (that produces) less carbon emissions but bigger countries are contributing a lot," said landowner John Zedkaia. "I think they really (need) to step up, because pretty soon we're going to be one of the first countries (to go) underwater."
Exacerbating the climate threat, the Marshall Islands continue to grapple with the legacy of the U.S. nuclear weapon testing. From 1946 to 1958, the United States conducted 67 atomic-bomb tests in the islands, leaving widespread contamination.
In the late 1970s and early 1980s, cleanup crews gathered roughly 100,000 cubic yards of contaminated soil and about 6,000 cubic yards of radioactive debris from former nuclear test sites on Enewetak Atoll and placed it into an unlined crater on Runit Island.
The site was then sealed with a concrete dome made of 357 panels, creating what is now known as the Runit Dome.
A 2024 U.S. Department of Energy report concluded that even with climate change, including a hypothetical collapse of the dome in 2090, radiation exposure would remain low and not affect public health.
The dome has long worried residents. Rising seas, which are steadily encroaching on the structure, have intensified those fears.
Enewetak Senator Jack Ading was skeptical of the U.S. government's assurances, saying that since the dome was built without a lining underneath, it could have been leaking radiation and contaminating the surrounding marine ecosystem since its installation.
Roughly half of Enewetak's approximately 200 residents have moved to Hawaii or Majuro, seeking higher ground and better health services, according to Ading. "So yes, they're worried," he said.
At COP30 in Brazil, the Marshall Islands raised the issue of the United States' nuclear legacy within the broader context of climate justice. But Washington's absence from the summit, despite being the world's second-largest emitter of greenhouse gases, frustrated many Marshallese.
Recent remarks by U.S. President Donald Trump directing the resumption of nuclear testing, without specifying where, further unsettled communities still living with the consequences of past tests.
Kenneth Kedi, director of the Marshall Islands Nuclear Institute and a former speaker in the nation's parliament, said the country's two greatest challenges -- climate change and nuclear injustice -- are increasingly intertwined.
"These are the major issues that have had a profound impact on our lives and have changed the way we live," he said.
He warned that other Pacific nations should also be concerned, saying, "There is no seawall in the middle of the ocean" that can prevent a nuclear hazard from spreading.