This week an unusually high tide, sometimes called a king tide, swept through the island nation's capital city, Majuro. Even something as modest as a swelling tide can have an outsize effect in the Marshalls, which comprises low-lying islands in the Pacific Ocean -- the highest elevation in the entire island chain is just 10 meters.

"Around 1,000 people were displaced as a result of the king tide, and a number of family homes were completely wiped out by the encroaching seas," Marshall Islands Minister for Foreign Affairs Phillip Muller told FP by email. Muller said it was the worst king tide to hit the Marshalls in decades.

"On Tuesday, the cabinet declared a state of emergency, and government agencies are now in high gear to help the communities in Majuro to deal with the situation. But the cleanup has only just begun, and many of the Marshallese affected will never fully recover."

The tide washed through a landfill, picking up trash and sewage, and a cemetery, jostling gravesites. It also damaged buildings and homes. "We are hopeful that those houses that are far away enough from the shoreline that they may be able to be repaired in such a way that a similar tide within the next five to 10 years can be staved off," Marshall Islands Climate Change Minister Tony de Brum said, but he stressed that the king tide will have lingering effects. "When the king tides come, the salt inundates, it doesn't go away. . . . The salt remains in the soil and in the groundwater."

The Marshall Islands are periodically inundated by high tides like this. The country last suffered severe tidal flooding in June 2013, when tides washed over storm walls and flooded the Majuro airport and the home of the president. "The president tells me that he has since added another foot to the height of his protective sea wall," Muller says. "Such is the new reality of climate change in the Pacific."

The tide this week "is a combination of a little bit of everything," Steven Gill, a senior scientist at NOAA National Ocean Service's Center for Operational Oceanographic Products and Services, told FP. The highest tides, like this one, are associated with the alignment of the sun and moon during perigee -- the point at which the moon's orbit passes closest to Earth.

That's also being exacerbated by changes in sea level. "What we're noticing is that it really depends on what's going on with the sea levels," Gill said. He noted that "it can't be said it is entirely a matter of global warming," citing variations in sea level around the Pacific and seasonal variation, but said that "over the long term, there's an increasing sea level trend in that area."

The Intergovernmental Panel on Climate Change estimates that, on average, sea levels could rise between 28 and 98 centimeters over the next century, which would put much of the Marshall Islands underwater. "While we are doing what we can," Muller says, "even the most conservative estimates of sea-level rise, including from the latest U.S. National Climate Assessment, suggest that RMI [the Republic of the Marshall Islands] will literally be wiped off the map some time before the end of the century, given the appalling lack of effort by big emitters to reduce their greenhouse gas emissions."