Because of a “wobble” in the moon’s orbit, which is acting in concert with climate change-fueled rising sea levels, every coast in the United States is experiencing fast-growing high tide floods.

New research published recently in the journal Nature Climate Change by NASA and the University of Hawaii warns that future changes in the moon’s orbit might result in record flooding on Earth in the next decade.

Researchers discovered flooding in American coastal towns may be many times worse in the 2030s, when the next moon “wobble” is projected to begin, by mapping the National Oceanic and Atmospheric Administration’s (NOAA) sea-level rise scenarios, flooding thresholds, and astronomical cycles. They predict major infrastructure damage and community displacement as a result of the water.

While the study emphasizes the grave position that coastal towns are in, the lunar wobble is a natural phenomenon that was first documented in 1728. The moon’s orbit causes periods of greater and lower tides every 18.6 years, although they aren’t harmful in and of themselves.

“Earth’s typical daily tides are suppressed during half of the Moon’s 18.6-year cycle: high tides are lower than usual, and low tides are higher than normal,” NASA says. “Tides are magnified in the second part of the cycle, with high tides getting higher and low tides getting lower. High tides are only going to get higher as the world’s sea level rises. As a result, half of the 18.6-year lunar cycle reduces the influence of rising sea levels on high tides, while the other half increases it.”

Scientists, on the other hand, are more alarmed this time. The next high tide floods are anticipated to be more severe and frequent than ever before as sea levels rise owing to climate change, compounding already dire projections.

In 2019, the National Oceanic and Atmospheric Administration (NOAA) reported around 600 such floods. After another decade of sea-level rise, scientists predict three to four times that amount in the mid-2030s.

Based on the current study, these floods will emerge more often throughout the country and can occur in clusters lasting over a month, depending on the moon, Earth, and sun’s locations. Floods might occur as frequently as every day or every other day during certain alignments.

“Low-lying regions around sea level are becoming increasingly vulnerable and suffering as a result of rising floods, and the situation is only going to get worse,” NASA Administrator Bill Nelson said. “Coastal flooding on our coasts and throughout the world will continue to be exacerbated by the Moon’s gravitational pull, increasing sea levels, and climate change.”

Almost all of the United States’ continental coasts, as well as Hawaii and Guam, are likely to be affected. By the end of the century, sea-level rise is anticipated to have rendered hundreds of thousands of square kilometers of coastline untenable, displacing over 100 million people globally.

Researchers hope that their findings will spur more focused efforts to avert as many harmful effects on the environment and people’s welfare as possible before it becomes too late. While high tidal floods may not include as much water as hurricanes, their regularity poses a serious threat.

“What will have an impact is a cumulative effect over time,” said lead author Phil Thompson. “A firm cannot operate with its parking lot underwater if it floods 10 or 15 times each month. People lose their employment as a result of their inability to get to work. Sewage ponds have become a public health concern.”