Remember when sea-level rise was going to cause Pacific Islands to disappear? Never mind.

Coral atolls getting larger, not sinking according to new study using satellite data

Andrew Montford writes:

Close watchers of the climate scene will probably be familiar with the work of Kench et al., who put a big spanner in the works of the climate alarm community, by demonstrating that coral atolls, far from disappearing beneath the waves, had been getting bigger over the last few decades.

Now, a new paper in Nature Scientific Reports looks as though it is going to add a fairly substantial hammer blow to those same works. The authors, Luijendijk et al., have surveyed sandy beaches around the world using current and historic satellite photographs – the same approach used by Kench – and have found that, in contrast to what a simple ‘global warming equals sea level rise’ approach might predict, more are getting larger rather are shrinking.


Coastal zones constitute one of the most heavily populated and developed land zones in the world. Despite the utility and economic benefits that coasts provide, there is no reliable global-scale assessment of historical shoreline change trends. Here, via the use of freely available optical satellite images captured since 1984, in conjunction with sophisticated image interrogation and analysis methods, we present a global-scale assessment of the occurrence of sandy beaches and rates of shoreline change therein. Applying pixel-based supervised classification, we found that 31% of the world’s ice-free shoreline are sandy. The application of an automated shoreline detection method to the sandy shorelines thus identified resulted in a global dataset of shoreline change rates for the 33 year period 1984–2016. Analysis of the satellite derived shoreline data indicates that 24% of the world’s sandy beaches are eroding at rates exceeding 0.5?m/yr, while 28% are accreting and 48% are stable. The majority of the sandy shorelines in marine protected areas are eroding, raising cause for serious concern.

Full paper

Willis identified this a long time ago on WUWT. I’d say his work has been vindicated.


64 thoughts on “Remember when sea-level rise was going to cause Pacific Islands to disappear? Never mind.

      • Considering both use “science” honorifically instead of actually applying its methods you’re spot on. Christian Science is another example of a pseudo scientific religion

  1. I guess Richard Branson also knew when he was buying his private island while touring with that other beachfront buyer Al Gore.

  2. The beaches and atolls are getting larger? Why that must mean that the oceans are evaporating faster due to anthropogenic global warming! (sarc/off)

  3. I don’t see how this study, about beaches worldwide and which doesn’t specify what is happening to coral atolls in particular (the words coral and atoll do not even appear in the study), can vindicate anything being told about coral atolls by anyone previously. Do coral atolls represent any significant amount of the total area of beaches in the world?

    • The point being that sea level rise would affect the atolls 1st since they are so low in the sea like Holland is. That being said, the whole argument really doesnt have anything to do with sea level rise because of plate tectonics, growth of of volcanic islands …..etc. However it was just another scare story of the alarmists that has been refuted.

      • Of course, those coral atolls wouldn’t even be there if sea level hadn’t been higher in the past… that’s sort of how coral atolls work, after all. You know, higher sea level… like the Holocene Highstand… which is why most coral atolls are no more than a couple meters above current sea level. This has been known since 1842.

        A volcano creates a caldera, that caldera is eroded over time until it is underwater, whereupon coral can begin growing on it.

        When sea level rises, the coral grows to reach the depth at which the coral receives the amount of sunlight necessary for maximum growth.

        When sea level subsequently falls, that higher-standing coral is uncovered, creating coral atolls.

    • The usual symptom of rising sea level relative to land is a shrinking beach. Authors of the paper appear to be assuming increasing beach width must mean dropping sea level relative to land.

      However, isostatic rebound of land is the primary factor affecting relative sea level in the northern hemisphere. I am going to guess that land rising due to isostatic rebound is balanced by land falling to the south of the pivot line.

      Each passing storm also washes away some beach sand. Beach sand is replenished by sand carried to the sea by rivers. An equilibrium is established. Dam building reduces sand carried to the sea by rivers. Jetties built at river mouths also reduces quantity of sand deposited on adjacent beaches. That beaches on average are expanding despite dam and jetty building may mean storms are not removing as much sand as previously.

      Another possibility is that increasing rainfall is increasing inland erosion in some areas, causing more sand to be carried to the sea. Increased rainfall would be balanced by increased evaporation from the seas.

      Increased overall beach area may have multiple causes, but rising sea level is not one of the possible causes. This means atolls are not threatened by an rising sea levels, to answer your question.


      • “Authors of the paper appear to be assuming increasing beach width must mean dropping sea level relative to land.”

        No. Accretion/Erosion is to a large extent independent of sea level.

        “However, isostatic rebound of land is the primary factor affecting relative sea level in the northern hemisphere.”

        However in those areas glacial scouring has removed most of the sand. Just try to find a sandy beach in Scandinavia or British Columbia. It isn’t easy.

        “Each passing storm also washes away some beach sand. ”

        Except for the ones that wash up more beach sand. Actually most storms do both, but in different places.

        • “No. Accretion/Erosion is to a large extent independent of sea level.”
          Yes, I mentioned a few factors affecting accretion and erosion other than sea level change. But where there is a beach, falling sea level will expose more beach while rising sea level will reduce the visible beach.

          “Except for the ones that wash up more beach sand. Actually most storms do both, but in different places.”
          Rivers deposit sand at their mouths. Wave action moves sand along the beach. Storms move the sand along faster than normal – temporarily outrunning the supply. Each storm results in a large area with reduced sand level and only occasionally a small area at the far limits of the storm affected area with higher sand levels. The net effect is lower sand levels after a storm. (Normal wave action moves replacement sand into the depleted section gradually over time in the years following a storm. see fig. 13-8: ) I’ve witnessed beaches in California that lost over 10 feet in one storm. I have also seen many newspaper reports of beach erosion due to storms. I have never seen a news report of a storm waves pushing sand into a city street or beach parking lot. (I have seen sand moved by wind .)

          “However in those areas glacial scouring has removed most of the sand. Just try to find a sandy beach in Scandinavia or British Columbia. It isn’t easy.”
          The article is addressing existing beaches, rare or not. Your point is lost on me. What is it?


      • There are also some questions about the accuracy of the method, as they acknowledge in the paper. They seem to get over the issue of tidal variations by averaging. I wonder if that’s good enough though. For places with a large tidal range, the beach width can vary by more than 100m depending on the state of the tide. They also note some issues caused by surf which can be wrongly classified as beach.

      • Atolls are a product of plate tectonic subsidence combined with the growing rate of coral and have little to do with sand deposition and erosion anyway. Sea level change, no matter what it is, is an insignificant factor in atoll formation since coral is capable of growing 5-10 times as fast as the sea level changes if conditions are right and plate subsidence can occur faster as well. What matters for atolls is the relation between the underlying plate subsiding and the conditions favorable for coral growth. If one is greater than the other then you either end up with a sea mount (and the hysterics blame global warming for the islands submergence), OR you get a raised coral island like Niue in the South Pacific and it doesn’t make the news.

    • Dear Nylo.

      Atolls are 100% sand.

      [??? The Marines on Midway, Tarawa, and a few other atoll-island groups in the Pacific would disagree with you. .mod]

        • The part of atolls that rise above the surface is coral sand. Reason: corals don’t live in air.

          Coral limestone is only found on land on islands that have been tectonically lifted so that former coral reefs are now above the surface. These are typically not atolls, since they don’t have a lagoon (rare exceptions do occur).

          Of course there are “transitional atolls” where the volcano or volcanoes that the atoll was built around has not completely eroded away and still exist as “high islands” within an atoll. They are rather rare. The famous Japanese base Truk (now Chuuk) is such a transitional atoll, and was indeed chosen as the main japanese base in the South Pacific for this very reason (both a spacious lagoon anchorage, and enough land for base installations and airfields).

          For your information I have visited both submerged coral reefs, true atolls, raised atolls, transitional atolls and high islands with and without a fringing reef, and am familiar with their characteristics.

          • Incorrect, go visit a few, the ocean was ~4 meters higher just 4k to 5k yr bp.

            A sand island is actually called a Kay.

            An atoll is a weathered-out volcanic cone from the upper part of a sea-mount, that arose above the waves, and which has since weathered back to sea-level again. The coral that was growing on its outer cone margins then covers the resulting submerged reef-flat. Why submerged? Because for most of the Quarternary’s glacials it was above the waves and still eroding away. The coral tends to build them back up during the interglacials. The sand is just a veneer over basaltic oceanic crust volcano with a thin layer of coral on its top.

            Hence, “coral atoll”.

    • The point is, we are supposed to be swimming in a 20-foot rise of sea level from Hansen’s 1986 ‘prophesy’ for 2006. That deadline overdue they pushed it to 2016. Now overdue that latest prediction by two years, and those dang shorelines refuse to cooperate. The one thing we know for sure from AGWrs, not one of the predictions has failed! [/sarc]

  4. When the global sealevel was 400+ feet lower 15,000 or so years ago were these Atolls 400+ feet above sea-level? I suspect they rise with sea-level.

    • After the Riss-Würm interglacial period which ended about 115,000 years ago these Atolls must have been much higher. So falling sea level is much more destructive than rising sea level for an Atoll..

    • Yes, the atolls were 400′ higher above sea level. A terrace is formed around the atolls during long periods of sea level stillstand. The terrace formed during the last glacial period is now several hundred feet underwater.

    • They were dry karstic limestone plateaus during glaciations. You can actually see what such islands look like since, despite the very high current sea-level, there are a few such ex-atolls around that have been raised by tectonics, none as high as 400 feet though. Lifu in the Loyalty Group, Mangareva, Niue and Henderson island are cases that come to mind.

      Lifu for example has been rising for a long time, and so each interglacial has left a new terrace, lower than the older ones.

    • And I’m pretty sure they were doing fine when sea-levels were higher 2000 or so years ago during the Roman Warm Period. Ephesus, a port city in the days of the Caesars, is now over a mile from the sea.

      • I think you’ll find that is land rising. It’s the same for Beaumaris and Harlech castles and the Cinque ports in Britain.

        Concerning atolls, they do rise with the seas, however not all atolls today were atolls in the last interglacial. Henderson Island is one such, which is why its flat top is nearly 10 metres above sea level, SL was much higher last time.

        There is a very good argument that much of the GBR and many atolls were not there in the last interglacial because if they were, they would be far higher above SL than they are now.

        • Atolls are volcanic sea-mounts. The can still erupt unseen at depth around their mairgins (examples of this have been observed). Fresh hot magma intrusions in areas around these can inflate large magma chambers. Hence both minor rises and falls are potential localised isostatic adjustnents, that are continually over-printing global sea level changes.

          In other words, atolls are total rubbish for getting a reliable measure of what global sea level is actually doing.

          Only a fool, or the ABC, would consider atoll island’s ups and downs as indicators of actual global sea level change.

      • Actually a number of atolls lost their freshwater lenses during the higher sea-levels in the Mid-Holocene and became barren.

  5. The only thing that seems to be ‘even worse than we thought’ were warmist predictions.

  6. … 24% of the world’s sandy beaches are eroding at rates exceeding 0.5?m/yr, while 28% are accreting …

    Shorelines have been eroding and accreting forever. link There are ways you can try to prevent your shoreline from eroding.

    Unfortunately, nearly all these methods have shortcomings.

    If a beach is eroding faster than 0.5 m/yr (20 inches per year), the tiny increase in sea level will be two orders of magnitude less. In other words, sea level rise won’t matter.

    • Do not confuse beach “width” (from start of beach to start of ocean) with water level. Typically an inch of sea level rise will take away many inches of beach width. But it depends on the beach inclination.

      • No, there is no “typical” transgression or regression of beaches. It depends on local factors: uplift/subsidence, sedimentation rates, sediment type, normal wave base, storm wave base, and ramp dip as well as maturity. That’s why real scientists only refer to global sea level rising or falling when it is universal among all beaches across the globe, indicating that eustasy has overwhelmed the aforementioned local factors.

    • If we talk about sand beaches we talk about parts of mountains transported there by mostly rivers. Everything you build which prevents these mountains to move to the sea like a dam will have negative effect on the beach.

  7. Don’t confuse the issue with truth! Truth is not wanted, and neither is rational thought. We are simply required to believe.

    “We must not think. We must believe. Believe, Katie, even if your mind objects. Don’t think. Believe. Trust your heart, not your brain. Don’t think. Feel. Believe.”

    ——Ellsworth Toohey quote, The Fountainhead, by Ayn Rand.

  8. Remember when Build-A-Bear brought us that heart-warming story[1] of a penguin that helped Save The Planet by raising awareness of “global warming” in the Arctic?
    Well, they have just hit the headlines in the UK[2] because they under-estimated the rate of rise of customers who would respond to its complete giveaway offer.
    At this moment it is the second most-read story on the BBC News website, after the latest on Trump’s arrival in the UK. Who can blame shoppers or climate researchers for making bids if you open up a stall giving away cash in exchange for filling an application form?

    [1] Under the North Star: (3-parts, 20 min total)
    [2] Build-A-Bear ‘pay your age’ offer abandoned amid ‘chaos’

    • “When I look back I will probably think, ‘what have I done that for?’, especially with what I will end up paying for parking.””


    • I’ve never heard about Build-A-Bear. I don’t feel like researching it either. Call me lazy. Anyway, this quote gets me:

      … a penguin that helped Save The Planet by raising awareness of “global warming” in the Arctic?

      Penguins do not exist in the Arctic. Given the healthy polar bear population (not to mention wolves and foxes), the dearth of penguins is unsurprising.

      • I won’t suggest you waste twenty minutes of your life that you won’t get back, so I’ll give you the gist. The penguins live in the Antarctic. They hear from their school-teacher about the imminent risk of global warming, notably that the Arctic Ice will melt and Santa Claus’s home will disappear. One of them, seriously emotionally affected, flies in a balloon to the North Pole and forms an alliance with the drowning polar bears. IIRC, he recruits Santa Claus and his family into tackling “climate change” using the Al Gore video of melting Arctic, and ice cube demonstrations. The story seems to end there (at video 3/3) in a sort of Hitchcock The Birds ending, so I am unclear whether Build-a-Bear responded to the ridiculing they got on YouTube or whether the scares moved on to another target, or whether film was complete as it is.

        If, despite this health warning, you choose to watch the entire production, here it is:
        Part 1:
        Part 2:
        Part 3:

        The YouTube comments are far more interesting than the film, even thought the latter is worth preserving as a gem of alarmist propaganda!

      • They do exist in the Tropics though. And actually in the Northern Hemisphere. The northernmost colony in the Galapagos is just north of the Equator.

        And once there were “penguins” in the North Atlantic. The name originally applied to the Great Auk Pinguinus impennis. Though it wasn’t an arctic bird. Unfortunately, because if it had been it would probably not have been exterminated.

  9. This makes excellent sense. If you really think about it the whole phenomenon of “a sandy beach” or a “sand-spit” or “a boulder-bank” can only be created when sea-levels are rising. The moment sea-levels begin to drop no further accretion will occur. During glacial ages those phenomena just remain there, probably getting vegetated – until the next inter-glacial episode.

  10. For those of us who spend a significant amount of our lives researching and writing about the extremist falsehoods of global warming alarmism and costly, intermittent green energy fraud, WHY DO WE DO IT? WHAT DRIVES US? WHY IS IT IMPORTANT?


    I have two engineering degrees and have worked on major energy projects on six continents. I am an energy expert with an outstanding track record of being correct on major issues. I have major career accomplishments that improved energy systems on a global scale.

    Since 1985 I have studied the hypothesis of catastrophic man-made global warming and wilder weather, allegedly due to increasing atmospheric CO2, and have found NO credible evidence that it exists, and ample evidence that that is false and fabricated.

    There is ample scientific evidence that “the science IS settled”, and catastrophic manmade global warming is a false crisis.

    Cheap, abundant reliable energy is the lifeblood of society. It IS that simple.

    There is further evidence that global warming alarmism has become a political , rather than a scientific matter, and is now a “false front” for extreme leftist political propaganda intended to control governments and societies.

    Here is my WHY:

    I have seen great human suffering in countries with brutal, corrupt, dictatorial governments and dysfunctional socialist systems. This human suffering is entirely avoidable, it is the product of scoundrels and imbeciles, and it must stop if humanity is to progress.

    Global warming alarmism is now a political scam that has cost society tens of trillions of dollars of scarce global resources, funds that could have put safe drinking water and sanitation systems into every village in the world and run then forever, and could have gone a long way to eliminating world hunger.

    Tens of millions of lives, mostly children, have been lost needlessly due to the global warming scam. The global warming scam parallels in many ways the banning of DDT, which also caused the deaths of tens of millions, mostly children under five.

    My core values as a man are to protect those weaker than me, and especially to protect children from harm. Global warming alarmism, like the banning of DDT, is causing the needless suffering and death of millions of children, as well as their parents. It is the greatest scam, in dollar terms, in the history of humanity, and it must be stopped.

    Regards to all, Allan MacRae, P.Eng.

    Watch this short powerful video – Simon Sinek – “Start with Why!”
    Why? > How? > What?

  11. Yet more empirical data showing that, if you want to be technical and correct regarding sea level, sea levels are not rising, they are at standstill.

  12. Somewhere I have Darwin’s book on the subject. His hypothesis was long rejected by the “scientists” of his day and long afterwards/

  13. The paper says nothing about atolls and ‘islands’ are only mentioned in the phrase “barrier islands”. The sub-title of this article “Coral atolls getting larger, not sinking according to new study using satellite data” is not supported by the paper.

  14. Isn’r nature marvelous! River deltas and coral atolls understand more about sea level that climate “scientists”.

  15. The abstract sounded like science, even including quantitative statements to back up what they were saying, until the editorial mandate of chicken-little-ism at the end.

    “The majority of the sandy shorelines in marine protected areas are eroding, raising cause for serious concern.”

    But in the actual paper it says:

    “Our analysis indicates that 32% of all marine protected shorelines are sandy of which 37% are eroding at a rate larger than 0.5 m/yr, while 32% are accreting.”

    Maybe they need a 5th grade English teacher to help them write more accurately and concise, but I bet it was editorial extortion — we won’t publish your paper until you invoke your inner chicken-little.

  16. That makes perfect sense – sea level is rising more slowly today than it has been for most of the past 18,000 years.

  17. somebody didnt read the actual article.
    also cool how satillites with 2 to 15 m resolution can detect such small rates of change.

    do read the actual article.

    nothing to do with sea level.

  18. Oh, come now! Everyone knows islands are going to tip over and capsize because of too many Marines being put on them! 😉

  19. Ive commented on what happens to coral islands and river deltas with sea level rise – they rise with it. The mechanics of deltas are such, that when sea level rises, water goes up the stream a ways, but this moves still water upstream and when river flow with its burden of sediment hits still water, it slows, drops its burden raising the bed of the river and causing the delta to build further out into the gulf. Weve known this for centuries.

    To a linear thinker’s “common sense” the ocean acts like a bath tub. If you add water (from melting land ice), the islands and deltas disappear. This is the childish a priori reasoning that Malthusian types bring to their analyses. It all seems so logical. But it isnt!

  20. Volcanoes rise When They are active and fall down again When They are dead. Coral Islands are a living organism that builds When The top of The Crater gest below sealevel. One place They found The original top of The Crater 800 meters below sealevel. At The END of The last iceage sealevel rose 130 meters. So me mot worry.

  21. The sub-heading of the above article reads:

    “Coral atolls getting larger, not sinking according to new study using satellite data”

    I downloaded the study in question, which is entitled “The State of the World’s Beaches”, and used ‘Microsoft Word’ to search for the words “coral”, “atoll” and “atolls”. They do not appear. The study is about beaches, not coral atolls.

    Nor does the study consider the effect of sea level rise on beach erosion or accretion. In fact it states explicitly that “random deviation from ‘mean sea level… is assumed to have a limited effect on the 33-year trend of shoreline change”.

    One interesting point to note is that in Table 2 of the study they list the 7 beaches classified as being the most “Erosive Hot Spots” globally and 4 of these are on the US east coast : Freeport, Texas; Rockefeller Reserve, Louisiana; High Island, Texas; and Hog Island, Virginia. Collectively these beaches are eroding at a rate of over 760,000 m2/yr (about 0.3 miles2/yr).

    Does anyone think this is the result of sea level rise on the east coast USA? If not, then why should we think that beach accretion is the result of a ‘lack’ of sea level rise elsewhere?

  22. but, just think how much bigger they would be if it weren’t for Global Warming…

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