{"id":73265,"date":"2021-07-26T22:30:00","date_gmt":"2021-07-27T06:30:00","guid":{"rendered":"https:\/\/www.juneauempire.com\/news\/researcher-moon-wobble-unlikely-to-flood-juneau\/"},"modified":"2021-07-26T22:30:00","modified_gmt":"2021-07-27T06:30:00","slug":"researcher-moon-wobble-unlikely-to-flood-juneau","status":"publish","type":"post","link":"https:\/\/www.juneauempire.com\/news\/researcher-moon-wobble-unlikely-to-flood-juneau\/","title":{"rendered":"Researcher: Moon wobble unlikely to flood Juneau"},"content":{"rendered":"
If recent predictions about increased coastal flooding during the next decade due to a moon wobble have you worried, you can scratch that off your list of concerns, at least for Southeast Alaska.<\/p>\n
According to an oceanographer involved with the study, Southeast Alaska faces a different phenomenon — declining ocean depths.<\/p>\n
William V. Sweet, an oceanographer with the National Oceanic and Atmospheric Administration, said ocean depths are dropping in Southeast Alaska as land rebounds from the retreat of glacial ice.<\/p>\n
“Land is springing up and rising out of the mantle,” Sweet said in a recent phone interview with the Empire. “Regional ice sheets are melting and retreating. They have tremendous mass so the crust is pushed down. When ice melts, the land rises back.”<\/p>\n
Sweet explained that the process is called “glacial rebound,” and even though sea levels are rising, the land is rising more quickly, which leads to lower overall sea levels in the area.<\/p>\n
New arboretum manager takes root<\/a><\/ins><\/p>\n The moon wobbles<\/strong><\/p>\n According to NASA’s website<\/a>, the moon wobble is a natural lunar process and is one of many factors that play a role in increasing or suppressing tidal fluctuations.<\/p>\n The moon is currently in an amplifying cycle, which will be followed by a cycle that reduces tidal fluctuations. However, when the next amplifying cycle occurs in the mid-2030s, sea levels will have risen around the planet, leading to increased coastal flooding in many places.<\/p>\n However, glacial rebound along with Southeast Alaska’s naturally dramatic tide fluctuations will mute the effect of the moon wobble in the region.<\/p>\n “It’s not to say that the wobble isn’t at play, it is anywhere there is a tide,” Sweet said. “It’s just not significant and it’s nothing compared to the tides you already have, which are among the most extreme in the country.”<\/p>\n Sweet said that the national study looked at several different factors to make predictions and that the totality of the changes is what matters for forecasts.<\/p>\n “You have to sum up several different factors. The variations in tide are significant but it’s the sea-level drop that’s critical,” he said.<\/p>\n