Told ya so: new paper proves that coral atolls keep up with sea level rise

From the “Tuvalu needs another climate handout” department comes this paper that says what we’ve been saying on WUWT for years – the sea level rise will overwhelm coral atolls in the Pacific is just political hype. For example, here’s a selection of some of our previous posts on the issue:

Now from the Geological Society of America:

Coral islands defy sea-level rise over the past century: Records from a central Pacific atoll

P.S. Kench, D. Thompson,M.R. Ford,H. Ogawa andR.F. McLean


The geological stability and existence of low-lying atoll nations is threatened by sea-level rise and climate change. Funafuti Atoll, in the tropical Pacific Ocean, has experienced some of the highest rates of sea-level rise (∼5.1 ± 0.7 mm/yr), totaling ∼0.30 ± 0.04 m over the past 60 yr. We analyzed six time slices of shoreline position over the past 118 yr at 29 islands of Funafuti Atoll to determine their physical response to recent sea-level rise. Despite the magnitude of this rise, no islands have been lost, the majority have enlarged, and there has been a 7.3% increase in net island area over the past century (A.D. 1897–2013). There is no evidence of heightened erosion over the past half-century as sea-level rise accelerated. Reef islands in Funafuti continually adjust their size, shape, and position in response to variations in boundary conditions, including storms, sediment supply, as well as sea level. Results suggest a more optimistic prognosis for the habitability of atoll nations and demonstrate the importance of resolving recent rates and styles of island change to inform adaptation strategies.

78 thoughts on “Told ya so: new paper proves that coral atolls keep up with sea level rise

  1. The amount of science left out of climate science is astounding. Everything has one cause. CO₂. It simply is not permitted to consider an alternative explanation. AGW continues pell-mell as a religion, a political system, and a hoax.

    • Indeed so much incorrect or inconsistent data used. In this report, page 13, it shows that none of the island is below sea level;
      The Low Countries, The Netherlands have over 50% of it land below sea level and the other half just about exceeding one meter above. We are not flooding, nor floating in our wooden shoes.
      Too much focus on poor countries, supposedly sinking with the aim of getting money from the rich countries. We built dikes years ago, without being subsidised, so go and built dikes to protect the land or built a Terp (artificial dwelling/hill) to survive on during high water levels. So annoying to sit and wait for help………..

  2. “There is no evidence of heightened erosion over the past half-century as sea-level rise accelerated.”

    There is no evidence that sea-level rise has ‘accelerated’.

  3. One of the purposes of Darwin’s voyage was to study the question of coral atoll formation. The imaginations of activist scientists have gone wild cooking up new crises contradicting settled science.

  4. Interesting. It is also interesting how only alarmistic stories end up in MSM, and optimism is left to WUWT and other blogs. I assume the MSM employs too many wannabe green activists compared to science journalists.

  5. Since carbonic acid will dissolve coral, perhaps they believe that the more acidic ocean because of the increased amount of CO2 will dissolve the coral reef? (Sarc off)

  6. Once again, WUWT is first past the post with the actual science … gotta love it.


    • “WUWT is first past the post with the actual science”

      While the rest of the field is running the opposite way, hair ablaze, with attention toward the falling sky…

    • From the “Tuvalu needs another climate handout” department comes this paper that says what we’ve been saying on WUWT for years – And I have independently checked out every Tuvalu style alarmist claim and they always wrong it ( A crooked is a crook is a crook)
      It’s amazing what sea level / AGW grant money will do to peoples honesty and the stupid first world nations that can’t wait to soak their own citizens for taxes of every kind and gleefully hand it over to the Tuvalu’s of the world.

      • “stupid first world nations that can’t wait to soak their own citizens for taxes of every kind and gleefully hand it over to the Tuvalu’s of the world.”

        It’s the politicians that gleefully hand over first world nation’s tax money.
        Usually during an all expenses paid trip to the “Tuvalu’s of the world”

        “A crooked is a crook is a crook”

        What you said…

  7. I have heard this from petroleum geologists for decades. They have mapped out huge coral reefs under Alberta that grew taller as the warm and shallow inland sea rose. They did not, of course, get shorter as the seas receded.

    • If You want to see a really impressive coral reef visit “El Capitan” in Guadalupe Mountains NP, Texas. The Guadalupe mountains is an eight thousand feet tall Permian barrier reef that formed as the Delaware Basin subsided. And remember that reefs can only grow in shallow water.

  8. According to Jevrejeva’s most recent paper there was no “acceleration” in global mean sea level in the last half century.

    In fact if one was to do something as inappropriate as to try to fit a straight line to this data, there would be a slight deceleration from 1950 – 2000.

  9. I’m thinking that much of the Great Barrier Reef would have been on dry land during the last glacial ice age

    Just think of all those coral reefs dealing with a relatively sudden 300 feet rise in sea level.

    • “I’m thinking that much of the Great Barrier Reef would have been on dry land during the last glacial ice age”

      It was, essentially all of it, and so was the very large submerged reefs to the east towards New Caledonia.

      And the Florida Keys are a barrier reef that formed during the previous (Sangamonian) interglacial when sea-level was slightly higher than now. Thus it has remained partly above sea-level this time, while the corals are busily building a new one a bit downslope.

      As a matter of fact it seems that such large barrier reefs is a relatively recent phenomenon that have only arisen in the last million years of “long” 100,000 year glacial cycles. During the previous 40,000-year cycles sea-level didn’t stay stable long enoug for really large reefs to form.

      • Reefs have probably been the most dynamic of all ecosystems throughout earth history. Throughout most of this time corals had little to do with reefs and instead bacteria, algae, sponges, bivalves, and bryozoans were the dominant reef builders. Scleractinian corals didn’t arrive until the Triassic and started to dominate in the Cretaceous. These reef builders survived the K-T extinction, the extremely warm Early Tertiary, the Late Tertiary/Quaternary ice age, and I’m sure they will survive the industrial revolution.

    • Exactly. The whole “coral reef disappearing” threats are lies, and I say that because the people uttering those lies know perfectly well they are not true.

    • The Great Barrier Reef complex is maybe 18 million years old but the current reef is around 8000 years old, built on a platform of older reefs.

      Around Australia and world wide the sea level was about 150m lower than today 18,000 years ago and reached approximately modern levels around 6000 years ago.

      For a bit of real sea level rise, the sea rose 16m in the 300 years between 14,600 and 14,300 years bp……that’s a bit over 1m every 20 years .

      That would give the warmistas something to think about…….

  10. It is very hard not to think that every climate ‘scientist’ is an idiot. I guess there are many who may not be idiots, perhaps a lot of them. But it is damn hard not to think them all idiots. This post is just one more data point bolstering my thinking.

    (and yes, I do know that some are smart and just dishonest … but who likes to think of that?)

    • Publish or perish. False alarms generate a lot of publicity. William Randolph Hearst discovered this principle, did not get a Nobel prize for it, but made a lot of money, creating modern mainstream media in the process.

  11. There are obviously some limits to this process. There are many flat-topped seamounts in the oceans that are now submerged to various depths. One of the most famous is the chain of Emporer sea mounts northwest of Hawaii. In most cases, they sunk as sea floors spread and subsided.

    • It would be interesting to correlate the age of the sinking of seamounts with an ocean surface temperature. Ice ages, for example? Plate tectonics?

      • I thought most of the sea mounts were undersea volcanoes that hadn’t reached the surface.

      • The sea mount chains tend to ride downward off of the midocean ridges, though in the Pacific very few if any of these ridges are in midocean. Exceptions include the Hawaiian/Emperor seamount chains which are the result of the mantle plume under Hawaii. Consequently, most sea mounts are in the process of sinking.

    • The Emperor Sea Mounts are NW of Kure Atoll which is near the Darwin Point — i.e. the sea temperature at which coral growth can keep up with sea level rise. SE of Kure there is a chain of reefs and volcanic islands that extends to the active volcanoes on the Island of Hawaii. NW of Kure — just sea mounts.

    • Seabottom subsidence goes on all the time while during glaciations, when sea-levels are low, the corals are living and making limestone well down-slope. If subsidence has gone too far the rapid sea-level rise at the end of an ice-age may “overtop” the island so fast and so far that the corals can’t live on the top of the seamount. Once this happens the island is doomed even though it may re-emerge several more times during glaciations.

      And of course this will also happen if plate tectonics carries the island out of the zone where hermatypic (=reef forming) corals can live.

    • The seamounts once were the visible Hawaiian islands, formed by volcanism over a hotspot [mantle plume]. The crustal plate they are on keeps pushing northerly, and so they slide past the hotspot, and cease to be volcanic. Oahu is destined to follow their path, both being eroded from the top and, because it is a great pile of cooling basaltic rock, becoming too dense to stand high. In essence it is subsiding down into the earth’s less dense mantle. Hawaii – the big island – is the present locus of the hotspot and now a new submarine volcano [Loihi] is erupting SW of it. Hawaii someday will be just a seamount.

    • Emporer sea mounts northwest of Hawaii
      living coral islands are rarely found outside the tropics. while coral is found in cold waters, it typically does not build the massive reefs and atolls found in the tropics.

      coral likes warm water. the idea that coral will be killed by warming if a pure fiction resulting from ignorance. coral is most abundant in the warmest ocean waters, such as the Red Sea. That is why the Great Barrier does not extent much further south than the Tropic of Capricorn. Brisbane at 27 S does not have an offshore reef.

      coral bleaching is a natural process as one species of coral is replaced by another, because some species do better than others, depending on water temperature. come back in a couple of years and the once bleached coral is now all healthy. What kills coral is fresh water, which is why atolls have passages on their leeward side.

      Humans also kill coral, mostly through fishing, logging, farming and city building. A coral reef needs fish to keep it healthy. Otherwise algae and will kill it. Anyone that has every owned an aquarium knows the problem with algae growing on the tank walls. The reef is no different. You need algae eaters to keep the reef healthy.

      Also, the increased silt carried by rivers and streams after areas are disturbed by humans smothers the coral. As well coral is used as a building material. As it is dredged this also affects the reef.

  12. Interesting. The geological world knows the concept of a keepup reef ( a reef that grows as sealevel rises) and of a catchup reef (a reef that catches up with sealevel after especially fast relative sealevel rise has partly submerged the reef).

    On the other hand, the geological record demonstrates drowned reefs too, where fast relative sealevel rise submerges the reef which no longer grows when it falls below the photic zone.

    However, these concepts are demonstrated at geological timescales by the geological record. This paper corroborates the idea that the concept of a keepup reef holds true at present historical timescales, and rates of sealevel change.

  13. Given the timescale of sea level change, hasn’t coral simply relocated over the centuries to a more suitable habitat?

  14. Maybe Britain can rule again and the conservatives can start putting an end to some of this nonsense. Let’s see what happens in Paris.

  15. Oh. My. God.

    As a life-long surfer, until a few moments ago I thought it was perfectly self-evident to anyone with a polyp for brain that coral reefs adjust to sea level. Competition for space and light is fierce, so corals will pile on top of one another until they reach a level where they are limited by low tide exposure.

    So this has actually been an issue? Incredible! Only total desk-sissies could be so bleeping detached from reality.

    Here is one of the best reef breaks on Earth — Teahupoo, Tahiti — testament to the fact that coral reefs adjust to sea level.

    • Yes, this is indeed obvious to anybody with field experience of atolls. It is for example particularly clear in the (relatively rare) cases where tectonics causes an atoll to rise rather than subside. Take for example Lifu, one of the Loyalty islands. It consists of a central, slightly concave plateau that was originally the lagoon inside the reef. Around this is a series of “steps” where each step marks the reef-flat just below low-tide level during a past interglacial, and finally the coast, with a reef-flat forming just below low-tide level.

    • with a reef-flat forming just below low-tide level.
      actually the reef flat often forms above the low tide level, the competition is so fierce. It is not unusual to find the outermost coral reef fully exposed at low tide, and fully covered at high tide. This can vary depending on windward/leeward conditions.

      typically you get very vigorous growth right at the windward edge, even though it is continually pounded by the breaking waves. which is why it is such a nonsense that the reef cannot keep up with sea level rise.

    • to get some idea of how vigorous a coral reef is, very few man-made objects can withstand the pounding that the windward side of a coral reef takes, day in a day out. typical trade wind conditions you have something like 8 foot waves crashing on the reef every 7 seconds of the day, every day.

      steel and concrete structures may survive for awhile. Until a hurricane comes along and the waves sweep the man-made structures away. the coral reef however will still be there. Any damage to the reef is simply a new opportunity for life. New real estate to colonize.

  16. Pretty much the same goes for river deltas (eg. The Nile). A delta is at the level it is because a river slows as it hits the sea and drops its sediement. If sea level drops, the delta drops, if sea level rise, the delta rises.

    • Yes, unless you build levees (like in the Mississippi delta) so the sediment goes out to sea before dropping. Or build a dam (like in the Nile) that catches the sediment before it reaches the delta.
      In such cases the delta will inevitably sink and erode and ultimately turn into a shallow sea, since all deltas are slowly subsiding because of compaction and the accumulated weight of sediments, and this will continue for many millenia after the sediment supply is cut off.
      Rebuilding New Orleans was probably not a good idea.

  17. The old school method of using the scientific method to determine results keeps getting in the way of the agenda. Next, maybe it’ll be rediscover that marine water isn’t “acidifying” because carbonate rocks and sediments react instantly to keep stoichiometric equilibrium when adding carbonic acid.

  18. I still can’t see how they can measure sea level rise without doing so from at least as far above the ocean as geostationary orbit. Even then it would have to be a tricky bit of math taking into account the potential wobble in the center of mass of the Earth, and would have to factor out lunar tidal effects to have any hope of accuracy within a decimeter. I’m betting we can ignore spacetime curvature, so it’s not all tensors and haggis.

    But otherwise you’re left with measurements taken from shorelines.

    Shorelines change. Water always wins, and anyplace flat enough to live on will have subsidence issues, or the lucky few who live under a caldera might be rising.

    It’s very good that the atolls protect a place like the maldives, but wind, waves, and currents will ultimately have their say unless the seamounts upon which they depend are still slowly rising.

    • Not strictly true. Bob, parrot fish make the sand that builds the island as long as coral is available to supply the polyps that the fish eat.

    • wind, waves, and currents will ultimately have their say unless the seamounts upon which they depend are still slowly rising.
      it is the sinking of seamounts that creates coral atolls. rising seamounts would kill the coral. Volcanic seamounts typically sink due to their weight deforming the crust locally.

      atolls likely do have a finite lifespan (what doesn’t). As the seamount sinks and the coral grows higher and higher, eventually the structure is a risk of structural failure. the great weight of coral above will eventually exceed the material strength of the coral below. and large portions of the atoll may slide off into the abyss.

      humans face the same problem. you can only build so high, otherwise the weight of the building above will exceed the material strength of the building below, and the structure will collapse under its own weight.

  19. If coral atolls could NOT keep up with the current sea level rise, how did they survive at the end of the last ice age when the sea level rise was much faster than today?

    While we’re at it, how did sea life survive the high CO2 levels of 1,000–>2,000PPM of 50 to 300 million years ago?

    • “how did sea life survive the high CO2 levels of 1,000–>2,000PPM of 50 to 300 million years ago?”

      That was pure natural CO2. Everyone knows that man-made CO2 is destructive at levels above 350ppm 400ppm 450ppm.

    • Actually they can’t keep up with such a fast sea level rise, but they don’t have to, because at the glacial maximum the atolls were high limestone islands sticking up 300 feet or more above sea-level thanks to the efforts of corals during the previous interglacial. The corals just had to keep moving upslope.

  20. I studied geology in the 1950s and learned that coral reefs and river deltas keep pace with sea level rise and are eroded back down with sea level drop. I’ve commented a number of times during the babble about the Ganges delta and the atoll islands. As the ice maximum built up, sea level fell 120m or so and then when it melted again the sea level went back up again. Coral and the deltas have been moving up and down for eons.

    I can see we need some quiet monastery to get back to work during the present dark age and keep the records of knowledge archived until the next enlightenment makes it safe to release this knowledge again without risk of losing it. I remember when nutritionists discovered ‘fibre’ was good for our health about 30 years ago and harkened back to my granny who was born in 1878, admonishing me to eat my ‘ruffage’, you need it for your good health, young man! I’m waiting for someone to get a nobel prize for discovering the latent heat of fusion of water or some such as there seems to be so much confusion about global warming causing freezing of the Antarctic. I probably could have got a grant and publication in Science for my atoll and river delta discovery. No, that probably wouldn’t happen – politically wrong answer.

  21. The main real problem is usage of natural fresh water lenses faster than their natural rainfall replenishment.

    Solution, build solar stills and irrigate with the output. this will water the plants and then percolate into the lens stores and hopefully replenish them.

    how come that we do not see any real science or studies relating to this cheap and simple solution.

  22. Hah. If you’ve ever snorkeled around a ‘bommie’ on Australia’s Great Barrier Reef, you can see that they have grown that way (typically, a tall, vertical cylinder) precisely to keep up with rising sea levels over the last 6-8000 years. In fact that’s what the current patter on the reef explorer boats conveys: corals adapt to whatever Gaia throws at them.

  23. As a geologist (and given enough data), I would rather say “Funafuti Atoll, in the tropical Pacific Ocean, has experienced some of the highest rates of SUBSIDENCE….”

  24. Reblogged this on Climate Change Sanity and commented:
    I am rebloging a 12 May posting on WattsUpWithThat(WUWT) titled “Told ya so: New paper proves that coral atolls keep up with sea level rise.” The alarmists thought they had a great cause–more island people losing their ancestral home to fossil fuels. One of the atolls actually sued the Czech Republic saying that their burning of coal would be the cause of the loss of their atoll. Anthony Watts has been telling us that for more than ten years the alarmists were not right. Of interest, Watts points out the reasoning that the atolls keep up with the rise in sea level originated with Charles Darwin. The posting includes the abstract of a recent study about the atolls and sea level. In addition, reading the several publications on WUWT by Watts and several others provide the science behind the atolls survival for thousands of years of sea level rise.

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