{"id":316323,"date":"2026-03-06T17:41:14","date_gmt":"2026-03-06T17:41:14","guid":{"rendered":"https:\/\/www.newsbeep.com\/nz\/316323\/"},"modified":"2026-03-06T17:41:14","modified_gmt":"2026-03-06T17:41:14","slug":"the-sea-is-higher-than-we-thought-and-millions-more-are-at-risk-study-finds","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/nz\/316323\/","title":{"rendered":"The sea is higher than we thought, and millions more are at risk, study finds"},"content":{"rendered":"

Climate change<\/a>\u2019s rising seas may threaten tens of millions more people than scientists and government planners originally thought because of mistaken research assumptions on how high coastal waters already are, a new study said.<\/p>\n

Researchers studied hundreds of scientific studies and hazard assessments, calculating that about 90% of them underestimated baseline coastal water heights by an average of 1 foot, according to Wednesday\u2019s study in the journal Nature<\/a>. It\u2019s a far more frequent problem in the Global South, the Pacific and Southeast Asia<\/a>, and less so in Europe and along Atlantic coasts.<\/p>\n

The cause is a mismatch between the way sea and land altitudes are measured, said study co-author Philip Minderhoud, a hydrogeology professor at Wageningen University & Research in the Netherlands. And he attributed that to a \u201cmethodological blind spot\u201d between the different ways those two things are measured.<\/p>\n

\"DilrukshanDilrukshan Kumara looks at the ocean as he stands by the remains of his family\u2019s home in Iranawila, Sri Lanka, in 2023.Eranga Jayawardena \/ AP<\/p>\n

Each way measures their own areas properly, he said. But where sea meets land, there\u2019s a lot of factors that often don\u2019t get accounted for when satellites and land-based models are used. Studies that calculate sea level rise impact usually \u201cdo not look at the actual measured sea level so they used this zero-meter\u201d figure as a starting point, said lead author Katharina Seeger of the University of Padua in Italy. In some places in the Indo-Pacific, it\u2019s close to 3 feet, Minderhoud said.<\/p>\n

One simple way to understand that is that many studies assume sea levels without waves or currents, when the reality at the water\u2019s edge is of oceans constantly roiled by wind, tides, currents, changing temperatures and things like El Ni\u00f1o, Minderhoud and Seeger said.<\/p>\n

Adjusting to a more accurate coastal height baseline means that if seas rise by a little more than 3 feet \u2014 as some studies suggest will happen by the end of the century \u2014 waters could inundate up to 37% more land and threaten 77 million to 132 million more people, the study said.<\/p>\n

\"\"\/<\/p>\n

That would trigger problems in planning and paying for the impacts of a warming world.<\/p>\n

\u201cYou have a lot of people here for whom the risk of extreme flooding is much higher than people thought,\u201d said Anders Levermann, a climate scientist at the Potsdam Institute for Climate Impacts Research in Germany, who wasn\u2019t part of the study. And Southeast Asia, where the study finds the biggest discrepancy, has the most people already threatened by sea level rise, he said.<\/p>\n

Minderhoud pointed to island nations in that region as an area where the reality of the discrepancy hits home.<\/p>\n

For 17-year-old climate activist Vepaiamele Trief, the projections aren\u2019t abstract. On her island home in the South Pacific archipelago of Vanuatu, the shoreline has visibly retreated within her short lifetime, with beaches eroded, coastal trees uprooted and some homes now barely 3 feet from the sea at high tide. On her grandmother\u2019s island of Ambae, a coastal road from the airport to her village has been rerouted inland because of encroaching water. Graves have been submerged and entire ways of life feel under threat.<\/p>\n

\u201cThese studies, they aren\u2019t just words on a paper. They aren\u2019t just numbers. They\u2019re people\u2019s actual livelihoods,\u201d she said. \u201cPut yourself in the shoes of our coastal communities \u2014 their lives are going to be completely overturned because of sea level rise and climate change.\u201d<\/p>\n

This new study is pretty much about what is the truth on the ground.<\/p>\n

\"ClimateChildren playing on an uprooted tree along a beach in Mele, Vanuatu, in July. Annika Hammerschlag \/ AP<\/p>\n

Calculations that may be correct for the seas overall or for the land aren\u2019t quite right at that key intersection point of water and land, Seeger and Minderhoud said. It\u2019s especially true in the Pacific.<\/p>\n

\u201cTo understand how much higher a piece of land is than the water, you need to know the land elevation and the water elevation. And what this paper says the vast majority of studies have done is to just assume that zero in your land elevation dataset is the level of the water. When in fact, it\u2019s not,\u201d said sea level rise expert Ben Strauss, CEO of Climate Central. His 2019 study was one of the few the new paper said got it right.<\/p>\n

\u201cIt\u2019s just the baseline that you start from that people are getting wrong,\u201d said Strauss, who wasn\u2019t part of the research.<\/p>\n

Other outside scientists said that Minderhoud and Seeger may be making too much of the problem.<\/p>\n

\u201cI think they\u2019re exaggerating the implications for impact studies a bit \u2014 the problem is actually well understood, albeit addressed in a way that could probably be improved,\u201d said Gon\u00e9ri Le Cozannet, a scientist at the French geological survey. Most local planners know their coastal issues and plan accordingly, Rutgers University sea level expert Robert Kopp said.<\/p>\n","protected":false},"excerpt":{"rendered":"Climate change\u2019s rising seas may threaten tens of millions more people than scientists and government planners originally thought…\n","protected":false},"author":2,"featured_media":316324,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[22],"tags":[273,111,139,69,147],"class_list":["post-316323","post","type-post","status-publish","format-standard","has-post-thumbnail","category-environment","tag-environment","tag-new-zealand","tag-newzealand","tag-nz","tag-science"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/316323","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/comments?post=316323"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/316323\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media\/316324"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media?parent=316323"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/categories?post=316323"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/tags?post=316323"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}