Inconvenient Study: Sea level rise likely not to drown low-lying Pacific atolls

By H. Sterling Burnett

A new study published in Geology, the journal of the Geological Society of America, indicates even if seas continue to rise, low-lying islands and atolls, such as Kiribati, Tokelau, and Tuvalu and are likely to adapt to the rising seas rather than sink beneath them, contrary to climate model projections.

Lead author Megan Tuck, of the University of Auckland, teamed with Dr. Murray Ford, also from the University of Auckland, Professor Paul Kench, at Simon Fraser University in Canada, and Professor Gerd Masselink from the University of Plymouth in the UK to recreate the effect of rising seas using a scale model of tiny Fatato Island on the southeast rim of Funafuti Atoll in Tuvalu to test the ability of the real island to withstand predicted climate affects.

Fatato Island on the southeast rim of Funafuti Atoll in Tuvalu. The researchers recreated a scale model of tiny Fatato Island, an uninhabited island on the southeast rim of Funafuti Atoll in Tuvalu, to test the ability of the real island to withstand predicted climate affects.

The researchers simulated higher sea levels and storm-generated waves up to 4m in a 20 meter (m)-long water chute to replicate real-world sea levels of 0.5 m and 1 m. During the experiment, Tuck, et al., used lasers to track changes in the model as simulated sea levels rose, finding the crest of the island—its highest ground—actually increased 1.13m height as higher sea levels and strong wave action washed sand and gravel inland. The experiment found lower lying areas could decline as the height of the crest increased, though that might not occur because lower lying ground on such atolls and islands are “are continually replenished by sediment from the surrounding reef.”

This paper confirms earlier research by the same scientists in which, using aerial photos beginning in 1943 to track changes to the 101 islands that make up the Tuvalu archipelago, they found the islands’ land area grew by 2.9 percent or approximately 73.5 hectares over the past 40 years, even as sea levels rose.

Tuck, the lead author, says these two sets of findings show low-lying islands are more dynamic and resilient than is commonly assumed. Tuck said in a news release discussing the Geology paper:

“Atoll islands do not sit inert on the reef, instead the gravel and sand they are made up of shifts on the reef itself so that the land changes in response to environmental conditions,”

SOURCE: SciMex press release


The paper in Geology (behind paywall)

Physical modelling of the response of reef islands to sea-level rise

Summary

Sea-level rise simulation suggests that low-lying Pacific islands such as those in Tuvalu, Tokelau and Kiribati are likely to adapt to the effects of climate change rather than simply sink beneath the waves, according to Kiwi researchers. The researchers created 1:50 scale replica of the uninhabited island of Fatato in Tuvalu and submitted the model to rising water levels and mock storm-generated waves. They found that the highest part of the island actually got higher as rising sea levels and strong wave action washed sand and gravel toward it. They say this shows the islands may be more resilient than we thought as they may be able to change shape to adapt to the climate.

Abstract:

Sea-level rise and increased storminess are expected to destabilize low-lying reef islands formed on coral reef platforms, and increased flooding is expected to render them uninhabitable within the coming decades. Such projections are founded on the assumption that islands are geologically static landforms that will simply drown as sea-level rises. Here, we present evidence from physical model experiments of a reef island that demonstrates islands have the capability to morphodynamically respond to rising sea level through island accretion. Challenging outputs from existing models based on the assumption that islands are geomorphologically inert, results demonstrate that islands not only move laterally on reef platforms, but overwash processes provide a mechanism to build and maintain the freeboard of islands above sea level. Implications of island building are profound, as it will offset existing scenarios of dramatic increases in island flooding. Future predictive models must include the morphodynamic behavior of islands to better resolve flood impacts and future island vulnerability.


Of course, our own Willis Eschenbach was way ahead of these guys.

Advertisements

87 thoughts on “Inconvenient Study: Sea level rise likely not to drown low-lying Pacific atolls

    • Somehow half baked theories trump actual data.

      When you point at data that shows how things really work, people ignore you and just keep on bloviating.

      • Just no data to prove your intelligence .the water ines at 45,ooo ft prove that .
        Tip UTCthere is alot of nuclear reactors for the cheap too .

    • Darwin figured it out 175 years ago – even without knowing that the seas have risen 120 meters in only 14,000 years. Do these researchers really think they are the first to discover this?

      • I suspect a very big issue regarding this is the utter lack of study or acknowledgement of previous research in these areas.
        Ignoring the past allows some researchers to proclaim new discoveries, whilst they could have easily made these same discoveries by picking up a text book.

        • … they could have easily made these same discoveries by picking up a text book.

          Scientists like to cite the original research. I’ve never seen a citation for a first year physics text. The trouble is that the original work will be difficult to understand and there is plentiful opportunity for confusion and error. The first year text book, on the other hand, is written after people have thoroughly understood and simplified the concepts involved.

          Hansen cited a paper by Bode and made a fundamental error that Monckton et al gleefully pointed out. An electronics expert would understand the implicit assumptions made by Bode, who was working with vacuum tubes. Hansen clearly did not.

          When Hansen wrote his paper, there were a slew of textbooks that clearly explained feedback at any level of complexity you could desire. Hansen, good academic that he is, didn’t go looking. There’s no excuse for that kind of willful ignorance but that’s how academics seem to roll.

          • “Hansen cited a paper by Bode and made a fundamental error that Monckton et al gleefully pointed out. ”

            Monckton’s would be paper is a mess but should be published or rejected on legitimate grounds. In either case making claims that he has found “fundamental errors” as though it is established fact in misleading.

          • Greg August 6, 2019 at 10:56 am

            Actually, it’s really simple. If you’re going to do feedback analysis a la Bode, you have to specify and justify your choice of the reference level to which the input signal is compared. It’s fundamental.

            Monckton et al pointed out that Hansen seems to have ignored the reference level problem. That’s a fundamental problem if I ever saw one. It means that Hansen et al miscalculated the system gain.

            Personally, I think Hansen’s use of feedback analysis is inappropriate. Monckton et al accepted, for sake of argument, that it was appropriate and then demonstrated that Hansen et al did the analysis wrong anyway.

      • Exactly. Darwin’s book published in 1841 remains valid regarding atolls and sea level rise, but the consistent, repeated science is somehow ignored in favor of mere drama. And thanks to Willis for correctly directing our attention to this several years ago.

  1. So it is recognizing that Charles Darwin was right, and the coral growth rate can keep up with either subsidence of the substrate or sea-level rise. Which is why a subsiding volcanic island becomes an atoll.

    • Not all volcanic islands are subsiding. However many volcanic cones do erode away, but not so much from wave action. The peaked cinder cones of the volcano are made of soft material and will erode due to wind and rain as the waves don’t quite reach that far. The run-off will surround the island with additional sediment, and because coral does not like to be buried under sediment it will cause a ring reef to grow (forming an atoll lagoon) .
      Wind and rain will continue to erode the cone until only its hard basalt (or granitic) core remains if any.
      Shield volcanoes (Hawaiian islands) ooze rather than spew ash and form wider flatter more durable islands as opposed to cinder cone volcanoes (Montserrat).

      I don’t believe shield volcanoes will form coral atolls due to their creation methods.
      Any geologists/volcanologists willing to expound upon this?

      • All volcanic islands are continually sinking into the crust.
        I posted on this about a week or two ago.
        The dynamics are well understood. The weight of the volcano causes subsidence into the crust.
        Virtually all the atolls are the remains of basalt(shield) volcanoes, because that is what you get at mid ocean volcanoes in the Pacific.

      • Midway Atoll is part of a chain of volcanic islands, atolls, and seamounts extending from Hawai’i up to the tip of the Aleutian Islands and known as the Hawaii-Emperor chain. Midway was formed roughly 28 million years ago when the seabed underneath it was over the same hotspot from which the Island of Hawai’i is now being formed. In fact, Midway was once a shield volcano perhaps as large as the island of Lana’i. As the volcano piled up lava flows building up the island, the load of it depressed the crust and the island slowly subsided over a period of millions of years, a process known as isostatic adjustment. As the island mass subsided, a coral reef around the former volcanic island was able to maintain itself near sea level by growing upwards. That reef is now over 160 m (516 ft) thick (Ladd, Tracey, & Gross, 1967; in the lagoon, 384 m or 1,261 ft), comprised mostly post-Miocene limestones with a layer of upper Miocene (Tertiary) sediments and lower Miocene (Tertiary e) limestones at the bottom overlying the basalts. What remains today is a shallow water atoll about 10 kilometers across.

        The islands of Midway Atoll have been extensively altered as a result of human habitation. Starting in 1869 with a project to blast the reefs and create a port on Sand Island, the ecology of Midway has been changing. Birds native to other NWHI islands, such as the Laysan Rail and Laysan Finch, were released at Midway. Ironwood trees from Australia were planted to act as windbreaks. Seventy-five percent of the 200 species of plants on Midway were introduced. The FWS has recently continued this trend by introducing the Laysan duck to the island, while, at the same time, extending efforts to exterminate other introduced species.

        The atoll has some 32 kilometers of roads, 7.8 kilometers of pipelines, one port (on Sand Island, which is closed to public use), and two runways (both paved, around 2,000 meters long). As of 2004, Henderson Field airfield at Midway Atoll has been designated as an emergency diversion airport for aircraft flying under ETOPS rules. The FWS closed all airport operations on November 22, 2004. Since that time, no public visitation at all has been allowed.

        https://www.cs.mcgill.ca/~rwest/wikispeedia/wpcd/wp/m/Midway_Atoll.htm

  2. good grief…it’s 3.1mm/yr……that’s 1 inch a decade…..10 inches in 100 years

    9 inches total since 1880……140 years

    • Closer to 1.6 mm/yr per tide gauge data. The 3.1 mm/yr number comes from satellite altimetry which is likely errant.

      • I believe that is a worldwide average of all tide gages.
        The atolls of the Pacific are notable for having a generally lower than average rate of SLR.
        Here are link to those tide gage charts directly from the source.
        Note on this first one, Johnson Atoll, that the SLR is said to be ~0.75 mm/yr, and yet a look at the peaks on the graph show no up trend at all. Recent peaks are no higher than the oldest ones, although more recent low points on the graph appear to not be as low as the older ones from several decades ago.
        This could easily be interpreted to mean there is no overall change.

        https://tidesandcurrents.noaa.gov/sltrends/sltrends_station.shtml?id=1619000

        Here are two links from which Pacific Islands and Atolls can be selected and examined.
        I am hard pressed to see a long term steady trend in any of them, prior to about the year 2000.
        Before that, they all just fluctuated up and down, but since then, then mostly all show an slow uptrend.
        Keep in mind that these charts are nothing like raw data…it is highly processed and are actually anomaly charts with many sources of variability removed, and then plotted against a baseline.
        Personally, knowing the people doing this are the same ones who made such a joke of pretty much every historical data set, taking any of the charts at face value is more of an exercise in trust than anything else, and IMO these people have amply demonstrated how trustworthy they are.
        https://tidesandcurrents.noaa.gov/sltrends/sltrends_us.html
        https://tidesandcurrents.noaa.gov/sltrends/sltrends_global.html

  3. I like the saying that the islands can “adapt to climate change”. Doh, that’s what they’ve been doing since their inception.

  4. Another example is the most beautiful place on earth IMO – Bora Bora. Apparently sinking at 1 centimeter/century. I think the coral reef might be able to keep up with that.

  5. I first made the claim that coral atolls were not in danger from sea level rise in a peer-reviewed article in Energy and Environment in 2004, fifteen years ago. It has since been cited in 24 other peer-reviewed journal articles.

    Six years later, I published the same ideas as a blog post here on WUWT entitled “Floating Islands“. My thanks to Anthony for being willing to publish that, as well as all of my work. And in some ways, my post here has been more influential and has had greater reach than my peer-reviewed paper. It’s the beauty of WUWT, it reaches almost everyone who is interested in climate science.

    I took a lot of grief for my study, especially in the early days, with lots of folks dissing either my scientific claims, or my scientific education (I have none), or both. Heck, there were even folks that seriously claimed that I was wrong because “Islands don’t float!” …

    As a result, I’m overjoyed that in the last few years, a number of scientists have come to the conclusion that I was quite correct in my statements.

    Anyhow, that’s the story of the re-discovery of coral atoll construction and growth, and I’m proud of my part in it. To be fair, I had a couple of advantages. First, I was just trying to point out to a bunch of willfully blind folks what Darwin had discovered a couple of centuries ago … and second, I’d just spent three years living on and diving around a coral atoll, so I’d seen firsthand the processes and the creatures that I was describing.

    The other post about reef dynamics that I’m quite proud of is my post entitled “Why The Parrotfish Should Be The National Bird“, as it highlights the plight of a keystone reef species that is endangered everywhere.

    Here on the coast, fog is rolling in, listening to the Giants baseball game with my gorgeous ex-fiancee, life is good. My best to all.

    w.

    • Willis: “The other post about reef dynamics that I’m quite proud of is my post entitled “Why The Parrotfish Should Be The National Bird“ […]”

      That was one of my favorite posts of yours; things I wouldn’t know if I didn’t read WUWT and nicely done by you.

      That post still jumps to mind whenever I read about sea level rise dooming some island or other.

      • Thanks for your kind words, H.R. I don’t write for popular acclaim … but it is indeed nice when it comes.

        w.

    • Absolutely, Willis, but I wonder about how accurate the “model” of those atolls were wrt ocean depths, extinct volcano slopes, trade wind patterns etc.

      When I was a kid and played mud puddles it was easy to model estuarine delta islands and see how they always stayed just above sea level around the entrance of powerful streams as they replicated the real world situation quite well.

      But I wonder how they modelled the Parrotfish?

      • Would be easier, and more fruitful, to model the influence of Parrot fish to their environment than the single fish themself.

        Don’t ya think. Too.

    • Thank you Willis for spending that time to research. We, armchair scientists, lack time to even look at the public data. Or read the existing studies beyond abstract level.

    • Wrasse species eat coral and pass the sand out their bums. Much of the coral sand of lagoons and atolls comes from them! Islands are dynamic.

    • I got my education on parrotfish poops in two ways.

      First, when my wife and I went on an anniversary trip to Tortola BVI, and did a snorkeling trip on a catamaran. When I cnorkeled on the several coral reefs we dropped anchor at around Tortola, I came out of the water and asked our charter captain, “What on earth is that loud chattering noise I hear down below?” He explained it was the parrotfish eating old dead coral using their powerful bony beaks, reducing the calcerous coral skeleton material to fine bits of white sand particles, and digesting the parasitic sea life living on the corals. That cacophony of sound quite impressed me!

      Then years later, I was working on a development project in the Bahamas, and we retained an environmental consulting firm to do the necessary environmental study so that we could get our development permit from the government. While flying over the Bahamas Bank and the vast stretches of white sand underlying the shallow aqua waters between islands and cays, I commented to the effect, “where did all that white sand come from?” And the consultant, sitting next to me, told me that it all came from parrotfish poop, built up over the eons of time, to an approximate thickness exceeding several thousand feet over the baserock .. and now covers tens of thousands of square miles of ocean bottom just in that small part of the world’s oceans, but replicated in many other places.

      That certainly impressed me! All due to nothing but coral reefs and a little fish! And a bunch of dissolved carbon dioxide in the ocean’s waters.

      • Duane

        I recently went to Tioman Island off the East coast of Malaysia. What you describe and what Willis tuned me in to is all in evidence. On the south end of Tioman there are very lumpy corals 20m from shore that are nearly impossible to walk on, broken and crumbling as they are, only 1/2 m below the surface. There is a huge amount of debris rolling back and forth (broken coral) mixed with coral sand, tearing at the coral bed. The amount of wear and tear is tremendous, resulting in a lovely white beach. Getting out 150 m, the water deepens and the coal is old and dead.

        Off the NW coast, snorkling was the right way to see things. The amazing range of corals living in the top 4-5 metres of water is delightful. Below that, in the much colder water, there is nothing save a million sea urchins nestled in the broken and apparently dead coral. The only living portion is that top 4 to 5 metres.

        Everywhere there were fish in the thousands, notably parrot fish. At another spot famous as a shark nursery and turtle haven, I observed the largest fish of all – again, parrot fish, huge and blue. What surprised me about all this was that below a certain depth it all looks dead and crumbling, with the living corals all near the surface. It might be temperature (it gets cold quickly as one descends) or the need for sunlight. The activity and growth at 2-4m depth was amazing. Canyons and valleys and the thousands of nibbling parrot fish. I am so happy Willis turned me onto this essential relationship.

        Deep into the sea, the coral looks as dead as a door nail. Broken, crumbling and largely barren. All the action is near the surface – 120m above where it was only 14,000 years ago. It is obvious how these ecosystems work and thrive in rising seas. There is some evidence on shore that sea level was 2m higher at some time in the recent past.

        • It is obvious how these ecosystems work and thrive in rising seas.

          Crispin,

          With that statement you have all you need to know about coral ecosystems.
          No biologist has ever recorded a living thriving coral ecosystem growing above sea level.

          The corollary of course is this: – Falling sea level is bad news for flat topped steep-sided coral atolls which can easily become exposed and the corals killed.
          In the case of Carbonate Ramps however with their shallow seabed gradient, such as the Emirates Coast in the Persian Gulf, each generation of new corals are able to migrate down-slope more easily and so the carbonate ramp ecosystem is able to survive sea level fall.

    • Willis,

      I have always read your blog posts and comments on this topic with great interest. So I’m also interested in the size of the study grant(s) that you’ve received over the years for all your research. That study proposal that involved 3 years diving around a coral atoll must have gotten you top dollar!

  6. Sediment transport is only one part of how coastal areas adapt to sea level rise.

    In tropical and subtropical seas, mangroves both trap sediment and anchor biological detritus that build the shoreline vertically. And coral reefs also migrate vertically with sea level rise, providing both mechanical protection from beach erosion as well as contributing new sediment (i.e., parrotfish poop).

    • Duane

      In addition to all of the mentioned sources of sediment from the breakdown of corals, there is the additional sediment source of calcareous algae.

      When I visited the Caicos Islands in 1991 on a carbonates sedimentology field trip organised by Hal Wanless of the University of Miami, we were shown the prolific growth of calcareous algae on the underwater stems of the mangroves on the lagoon side of Middle Caicos. These algae are the origin of Micrite, (lime mud) which is an additional abundant type of calcareous sediment that forms the shallow water tidal mud banks in which the mangroves grow. This link between the calcareous algae and the exposed mangrove roots on which the algae flourish is an example of biological sedimentation feedback.

      See also The Oceanic Central Heating Effect

      • Yes, Philip, that too.

        Wonderfully complex system we have where the climate, geology, and biosphere all work together in many varied ways!

        And to think that the bozo climate alarmists still pretend that the only thing that matters is the concentration of CO2 in the atmosphere. Only truly ignorant simpletons, no real scientists, could ever think that anything in nature is just one thing only, in total isolation from everything else in the universe.

  7. Coral can keep up with natural sea level rise, 200 ft or so since the last ice age. But with human induced climate change, the coral cannot keep up with sea level rise. Political science 101.

    Question: how does the coral know which is which? Natural or human induced. This is a great mystery. More research is needed.

    sarc off

    • The average sea level rise since the end of the last glaciation period has been about 1 meter per century, but there were some periods within the current interglacial during which SLR was about 2.5 meters per century.

      The current sea level rise today worldwide is only about 0.25 meters per century. Very slow … of course, that’s because most of the glaciers that existed at the end of the last glaciation period have already melted so there’s just not that much melting left to do before either it’s all gone, or the next glaciation period begins ..or at least a minor cooling phase like the “Little Ice Age”.

      • Yep. Alarmists often like to cite Meltwater Pulse 1a as an example of catastrophic sea level rise. The problem is that it occurred early during the last deglaciation… when there was a lot more ice.

        • Yes, David … I expect that only a very tiny percentage of those self-styled climate experts understand the least bit about system dynamics and rate equations that depend upon initial and current mass on the reaction rate of the system. Most chemists and engineers get it … ditto with astrophysicists and medical doctors too. Climate “experts” ??? Not much.

  8. Will someone tell the “cargo cult” political classes of these islands the truth? Or is it politically incorrect to do so?

  9. The Australian BOM is also way ahead of them. Have a look at the Pacific Sea Level and Geodetic Monitoring Project, http://www.bom.gov.au/pacific/projects/pslm/. Drill down to the monthly reports which carry tables and graphs of sea level rise over 14 Pacific Island countries. The project has been running for over 20 years.

  10. The global average sea level rise rate, as measured since 1992 using precision radar altimeters on the TOPEX, Jason-1, Jason-2, and Jason-3 spacecraft, is linear at 2.9 +/- 0.4 mm/year.

    Please get back to me 50 years from now when we will have seen what actually happened with about 6 inches of accumulated sea level rise . . . you know, something bordering “significant”. But even this may not happen if Earth enters another cooling period, like the LIA, before then.

  11. What the hell?

    1. I thought group think was rampant amongst the cultists!
    2. What were the gate keepers thinking! Doesn’t all science that fails to follow the party line get spiked!

    • Haven’t you ever gone to a party and woke up not knowing how you got where you got?

      Of course you have … that is how you ended up backing the non-science you do … the non-science you now know was a heap load of grass digested by a bull.

      • I’ve thought for a while now that Mosher has had that gnawing feeling he is on the wrong wagon, at least subliminally. He may be setting himself up by scolding skeptics for not doing good science so that in a decade or so he can say to the world “Hey guys, I was trying to help you out to make a better case for your skepticism. I knew all along you were right.”

        That will keep his record of always being right at a clean 100%.

  12. Know it well; the mushroom project.
    A project that didn’t quite spit out the data it was meant to so consequently it’s kind of the BOM’s best kept secret.
    Huge money, lots of red faces, no internal agreement on how to manipulate the data; consequently, no press releases, articles, new research based on PSLGM data.
    This UN directed Au Gov kow-tow via BOM kind a backfired but no matter the alarmists keep plugging on with the BOM press-releases that really matter when there’s an unusually hot day or two!

  13. Nice to know that these islands can replenish their altitudes, but is there a lesson to contemplate about airstrip management?
    Airstrips will not rise with sea level rise unless incoming sediment is able to wash over them and accumulate. Geoff S

    • Runways need resurfacing occasionally, and the easy way to do this is to spread a new surface on the old one.

      Making runways rise faster that the sea should be trivial for a well used airfield.

    • Don’t know about the runways, but a friend who lived in the mountains of Colorado for many years watched the county road in front of his cabin rise 1/4 inch per year when averaged over several years.

  14. How convenient. You can explain missing sea level rise by floating islands. Are continents floating too? New York, Miami and Stockholm., IIRC.

    Do we have data of the global ocean volume change? Judith Curry? Thermal expansion is not expected because, Argo shows next to zero temperature change. Temperatures at least in coastal areas follow sea water temperature.

    Human population lives in coastal areas. Land-locked areas miss cargo ships for cheap transport. So, people are planning floating cities. Boat homes exist already in Amsterdam.

    Climate crises cancelled. Sea level rise, if it happens, is not a problem.

  15. Meetings International invites you to Amsterdam, The Netherlands to be part of Coastal Zone 2019 Conference in September 2019 to discuss “Sustainable Management of Coastal Ecosystem- A Global Responsibility”.
    Participate as
    #Speakers or Delegates
    #Media Partner
    #Sponsors or Exhibitors
    We request you to be our Media Partner and help us in making this event a success.
    For details:
    https://www.meetingsint.com/conferences/coastalzone
    Joel Adams|+65-3158 1626
    coastalzone@insightsummits.com
    coastalzone3@gmail.com

    • HYDROGEOLOGY OF TARAWA ATOLL, KIRIBATI by G. Jacobson & F.J. Taylor, 1981…

      GEOLOGY
      Tarawa is a coral atoll formed on top of a volcanic seamount which rises steeply from 4000 m of water. The atoll is roughly triangular in plan and comprises a chain of small islands on the south and northeast sides which partially enclose a central lagoon (Fig. 2). The islands are generally 2-3 m above present sea level. The surface material of most of the islands is coral sand. In places, cemented coral hardpan forms a terrace 1.5-2 m above sea level. The first four bores drilled on Bonriki and Buariki intersected coral sand to depths of 7.5-11.5 m below the ground surface (Appendix 1). Beneath the sand, these bores intersected buried coral reef, 1.5-12.0 m thick. Beneath the buried coral reef, some of the bores encountered interbedded limestone and sand; others had a limestone sequence extending to 30 m below surface, the maximum depth of drilling. The total thickness of the limestone sequence is unknown. ^The nearest atoll to Tarawa that has previously been drilled is Funafuti in the Ellice Islands (Fig. 1), where volcanic basement was not encountered even at 330 m. The nearest atoll where basement has been intersected is Enewetok in the Marshall Islands, where basalt was encountered beneath 1300 m of limestone.

      https://d28rz98at9flks.cloudfront.net/13901/Rec1981_031.pdf

      Tarawa was 2-3 m above sea level in 1981… What is it today? “Highest elevation 3 m (10 ft)

      What was the elevation when the U.S. Marine Corps landed in 1943?

      Intelligence reports from Betio were sobering. The island, devoid of natural defilade positions and narrow enough to limit maneuver room, favored the defenders. Betio was less than three miles long, no broader than 800 yards at its widest point and contained no natural elevation higher than 10 feet above sea level. “Every place on the island can be covered by direct rifle and machine gun fire.” observed Edson.

      Betio, Tarawa Atoll 1943

      Betio, Tarawa Atoll today

      • 1300 meters.
        Proving that the volcanic peaks these islands are built upon are continually subsiding into the ocean crust.
        And yet we see atolls across the tropics in the Pacific.
        Every one of them has kept up with not only sea level rise, but continuous subsidence of the whole structure into the crust.

    • Did you read the study? It said the atolls can move laterally, can you live on an area that moves laterally?

      I think some people on here don’t actually care about the science. LOL

      Just when I thought i came across a site that might not be super biased. Ugh.

      • That’s lateral thinking for you Sean. Bit of a climactic change from the old glug glug glug meme wouldn’t you say?

      • Much of the state of CA is moving laterally as well. I guess that answers the question regarding habitability of laterally moving land.
        We do understand the science perhaps to a greater degree with a bit of perspective you lack?
        All sedimentary depositions change area regularly(islands, deltas, river bottoms, flood plains, etc.), but at such a pace as to NOT be an issue except when major storms or flooding occurs.

  16. Oh well, these scientists possibly got themselves taxpayer-funded carbon-spewing trips to these islands, nice gig. Those fancy umbrella drinks also most likely included in the expense account. The main question missed, did they use plastic straws?

  17. “The researchers simulated higher sea levels and storm-generated waves up to 4m in a 20 meter (m)-long water chute”

    4m waves at a scale of 1:50 would be the equivalent of a 200m wave … now I’ve heard that the climate cult make idiotic assertions but …

    • When making scale models of real sized physical objects engineers and scientist understand that certain physical characteristics of materials, water and and air, simply do not scale linearly like dimensions. Surface tension is one such property. Hollywood invariably cannot make a scaled flood scene without water droplets appearing the size of basketballs or even larger, when we know in reality that no such things would occur.

      Therefore we have created various “dimensionless” scaling factors based upon the phenomena we are attempting to measure at a reduced scale. This is what allows wind tunnel models of aircraft and ship models in a wave tank to generate meaningful data which can be verified in the real world. Often these values will require the actual physical object to have its physical dimensions altered to maintain these non-dimensional relationships. An airplane model being tested for in a water tank to determine external flow field creation must look different due to the differences between the density and viscosity of water versus air. It will look shorter and stubbier with more rounded features, but will yield essentially the same applicable measures as a model appropriately sized to fly in air.

      Perhaps you may have heard some of these mentioned:
      Reynolds number, for drag and flow and flow
      Froude number, for wave energy interaction
      list of several different “numbers” and their uses:
      https://en.wikipedia.org/wiki/List_of_dimensionless_quantities
      https://archive.siam.org/books/textbooks/MM13Sample.pdf

  18. The Wikipedia article for Tarawa states that Tarawa will be the first Pacific Island to be lost to rising sea levels, and the population will have to be evacuated to Fiji. What a load of tosh.

    • The study doesnt back what you are implying. The study says that the whole island can move laterally, which would imply the likelyhood that the population would have to move.

      I find it weird how people will take any information and try to change it to fit their narrative. These same scientists will tell you this is not generally good for the atolls that have people living on them… But it is good news for wildlife that is supported by these atolls.

      • Sean the manner in which you attempt to describe the situation doesn’t give me the impression that you understand the mechanics of the coastal dynamics of islands, or that through selective word choice are deliberately misconstruing the issue.

        Coastal deposition changes with wind wave and ocean current flows on islands…as with all land formations its called weathering. This process has been occurring and continues to occur on these islands long before man arrived. I suspect that the inhabitants may have needed to reposition their dwellings numerous times throughout the time they have occupied these islands.
        The east coast of the US is no exception either. On
        Cape Cod, out in Truro, the foundations of the original broadcast towers for Marconi’s trans-Atlantic wireless are presently several hundred yards out to sea and visible only during low tides if even then.
        The point its that the islands are not disappearing beneath the waves in any near future.

    • Matthew K August 6, 2019 at 12:24 am

      The Wikipedia article for Tarawa states that Tarawa will be the first Pacific Island to be lost to rising sea levels, and the population will have to be evacuated to Fiji. What a load of tosh.

      Tosh indeed. See my post “So Many People … So Little Rain“.

      w.

  19. During the experiment, Tuck, et al., used lasers to track changes in the model as simulated sea levels rose, finding the crest of the island—its highest ground—actually increased 1.13m.

    So pleased models & not real world data were used, I don’t like the real world, it’s so inconvenient! 😉

    • Allen the Brit, technical modelling is an old, fascinating tool and – happens in the real world.

      https://technology.tki.org.nz › Tech…

      Technological modelling / Technological knowledge / Technology in the NZC …

      Technological modelling is the testing of design ideas to see if they can contribute to a fit-for-purpose technological outcome. There are …

      http://www.vitroeurope.com › 3d-technica…

      3D Technical Modelling | Vitro Europe

      The latest technical devices need to be designed as 3D models before full scale production can begin and that means a tremendous …

      http://www.enterprisesciences.com › mode…

      Modeling and Simulation Services | – Enterprise Sciences, Inc.

      Custom Scientific and Technical Modeling – Some problems such as signal processing, image processing, and other data processing …

      https://www.google.com/search?q=technical+modelling&oq=technical+modell&aqs=chrome.

      Easy to scale lengths and weights, velocities, accelerations, …

      The challenges are scaling of turbulences in fluids, gases, …

      Think of model railroads and you know how old and real worldly this practices are.

      • Yes , very well put.
        Its a physical model, which does have its limitations too, not anything like a computer model to generate results far in the future

  20. I just read the paper, it doesnt make the claim it sounds like you are trying to make. Sure some of the islands will change, but from the study it doesnt look like low lilying atolls that are inhabited will be habitable with these constant changes.

    Isnt that the issue, not that they will still be there, but moved laterally.

      • So you are saying you dont actually care what the scientists are actually saying, and will stick to whatever your beliefs are?

        Sure there are people who will exploit climate change, but it isnt any different than people who take this study which says it is still bad for people living on an Atoll, and twist it to: Atolls are fine, people can live on one that move?

        • Sean,
          Your questions lead me to think you have a different understanding of what island movement is. Inhabitants are not experiencing earthquakes or ground shifting. It is only measureable on an island wide scale over years of time. These islands have been “moving” at essentially the same pace since their creation. It would take a major erosion event such as big storm or tsunami to create much of any noticeable difference .
          As to uninhabitable atolls, there are many now that may have been inhabited in the past and many which are currently uninhabitable but will become habitable in the future. Most due solely to weather, but the Chinese are having an effect on that number.

  21. That is unless you decide to increase activities which deter coral growth like expanding an airport to increase tourism, hotels and human solid waste discharge.

    • Waste discharge is a separate issue, but how exactly does construction on onshore infrastructure deter coral from growing offshore in the reef zones?

      • Changes to on-shore infrastructure such as increased impermeable surfaces (paved roadways, parking lots, etc.) will effect coastal run-off flows. You might categorize storm drain run-off as waste discharge, but they are two different sources.

  22. I have recently been reading a whole bunch of stuff from a variety of sources on the subject of Pacific islands, and one piece of information I came across is really very interesting but little noted: When volcano is in the process of growing and reaches the surface of the ocean, what happens as it break above the surface is very different than what occurs on established islands.
    It turns out that it is very difficult for the transition from sea mount to island to occur, because as they begin to poke above the surface, they are subject to extreme forces of erosion from wave action, far more than takes place where there are offshore reefs, where there is offshore sand banks, and where there is a island already above the waves and therefore not over-washed by every wave that comes along.
    Several times new islands have been seen to form temporarily from underwater active volcanoes, only to disappear ago at some later time, typically very quickly.
    But some do persist. To do so, it takes some combination of events, such as calm seas over a period of time the island is trying to first form, and of course a large amount of material erupting one the island has begun to form…enough to require a long time before it can erode away.
    Here are some links showing how fast they tend to erode and a little about how rare are new islands that persist for more than a few months. The first has some very cool time lapse videos of how quickly the waves take bites out of them:

    https://svs.gsfc.nasa.gov/4602

    https://svs.gsfc.nasa.gov/12800

    The sea mount in the Hawaiian chain called Lohoi is currently 3000 feet below the surface, and about 10,000 feet in height above the sea floor.
    It is expected to take “several tens of thousands of year”s to emerge above the waves, if it ever does. This is based on the growth rate of other volcanoes in the chain.
    https://geology.com/usgs/loihi-seamount/

    Compared to the number of seamounts (the name given to ones that do not break the surface at the present time), the number of islands is very small.
    I suspect this pay be due in part to the special conditions that must occur to make the transition from sea mount to an island with a considerable lifetime above the waves.

Comments are closed.