NASA HAS WARNED that a “wobble” in the moon’s orbit, combined with rising sea levels, will lead to a decade of high tide flooding in the 2030s. 

The space agency says that its research has shown that this flooding will likely occur due to rising sea levels caused by climate change and a shift in the moon’s orbit. 

The study, published by Nature Climate Change, looked solely at the impact on North America and did not analyse the impact on the rest of the world.

It predicts that the floods will affect almost all of the United States’ mainland coastlines, sometimes in clusters that could last a month or more. 

Hawaii and Guam will also be impacted, but northern coastlines, including Alaska’s, will be spared for another decade or longer because these land areas are rising due to long-term geological processes, researchers found.

The National Oceanic and Atmospheric Administration (NOAA) in the US reported a total of more than 600 floods in 2019. 

Nasa Administrator Bill Nelson said the combination of the moon’s gravitational pull, which causes tides in the first place, and climate change are the reasons behind the expected flooding.

“Low-lying areas near sea level are increasingly at risk and suffering due to the increased flooding, and it will only get worse,” he said.  

According to Nasa, the so-called ‘moon wobble’ is not a new phenomenon. It has occured  since 1728 and is part of an 18.6-year natural cycle.

During the first half of the moon’s cycle, the effect of sea-level rise on high tides is suppressed, while the other half increases the effect. 

While there is no imminent concern about the moon’s tide-amplifying cycle, Nasa Sea Level Change Team leader Ben Hamlington has said that because waters will be higher in the coming years, it could have a much more dramatic effect.

“We’re getting closer and closer to the flooding thresholds or tipping point in these coastal locations,” he said.

“The same variability in the past that didn’t cause flooding is now going to cause flooding.”

The study uncovered these tipping points in flood numbers by studying 89 tide gauge locations in every coastal US state except Alaska. 

Researchers then created a new statistical framework that mapped the NOAA’s widely used sea level rise scenarios and flooding thresholds, the number of times those thresholds have been exceeded annually, astronomical cycles, and statistical representations of other processes, such as El Niño events, that are known to affect tides.

They projected results to 2080.