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Rising Seas Give Island Nation a Stark Choice: Relocate or Elevate (nationalgeographic.com)

Climate change means the low-lying Marshall Islands must consider drastic measures, including building new artificial islands. National Geographic: The navigational prowess of Marshall Islanders is legendary. For thousands of years, Marshallese have embraced their watery environment, building a culture on more than 1,200 islands scattered across 750,000 square miles of ocean. But powerful tropical cyclones, damaged reefs and fisheries, worsening droughts, and sea-level rise threaten the coral reef atolls of this large ocean state, forcing the Marshallese to navigate a new reality.

In a moment of reckoning, Marshall Islanders face a stark choice: relocate or elevate. One idea being considered is the construction of a new island or raising an existing one. With 600 billion tons of melting ice flowing into oceans that are absorbing heat twice as fast as 18 years ago, the Marshallese will need to move fast. A report published by the Intergovernmental Panel on Climate Change (IPCC) in October highlighted different projected outcomes from a temperature rise of 1.5C versus 2C.

In the report, small-island developing states are identified as being at disproportionately higher risk of adverse consequences of global warming. Among them, four atoll nations: Kiribati, Tuvalu, the Maldives, and the Marshall Islands, are at greatest risk. [...] In July, speaking at a climate change conference on Majuro, capital of the Marshall Islands, University of Hawaii climate scientist Chip Fletcher discussed possible adaptation measures. When Fletcher presented a map depicting Majuro flooded under three feet of water, there was an audible gasp in the room. For climate activists in the Pacific, "1.5 to stay alive," has been the mantra of survival. "We're going to miss 1.5C," Fletcher told his audience, but added, "there's something we can do about it."

12 of 243 comments (clear)

  1. Theory vs. data by LynnwoodRooster · · Score: 4, Informative
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    Browsing at +1 - no ACs, I ignore their posts. So refreshing!
    1. Re:Theory vs. data by swillden · · Score: 5, Informative

      Data shows that coral-based islands (like the Marshalls) are growing. Eighty percent are either stable or growing. Tuvalu has added 3% more land in the last 50 years, and the Maldives, which famously held a cabinet meeting underwater to show their nation is doomed has no change in land area over the last 60 years.

      Coral atolls grow higher when sea levels rise. The question is one of rates. As long as the sea level rises are slow enough, the atolls will be more or less fine. But if the water rises faster than the corals can grow, they'll be inundated. Massive corals of the sort that make up these atoll reefs can grow up to 5mm per year. Over the 20th century the average annual sea level increase was 1.7mm. No problem, they can keep up with that. Since the 90s the rate has averaged 3.2mm per year. The corals can handle that, too... but the rate doesn't have to accelerate much more to overwhelm them.

      Indeed, even at current rates, islands are having problems. I was on Rarotonga last month, in the Cook Islands. Natives there told me that their lagoons used to be two to three times deeper than they are now. The problem is that seas are crashing higher over the reefs and depositing more sand, causing the lagoons to fill in. This has created problems for fishing and for the tourist industry (snorkeling in a foot of water isn't much fun). However, it's expected that over the next 20 years the waves will rise higher yet and begin removing sand from the lagoons and the beaches, reversing the shallowing trend and then beginning to eat away at the island. Rarotonga will be fine; it's volcanic and rises over 2000 feet above sea level at its highest point. At worst people will have to move inland a little bit. But it could easily devastate the already-fragile island economy.

      I was also on Mangaia and they're facing a different problem. Much of the island's fresh water supply comes from inland lakes which flow through tunnels in the makatea (fossil coral) to the ocean. But sea levels have risen enough that during storms water now flows in through the tunnels, turning the lakes brackish. This is having serious effects on the island ecosystems as well as making fresh water harder to come by.

      The bottom line is that for many islanders, climate change is already having very real and very visible effects, mostly due to rising sea levels. And it's going to get much worse. And many low-lying coral atolls may just disappear when the rate of sea level rise exceeds the rate at which the corals can grow.

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    2. Re:Theory vs. data by Jane+Q.+Public · · Score: 1, Informative

      Here are two revealing reports about the "ocean heat" paper.

      Author Resplandy has responded and thanked Mr Lewis for catching the mistakes.

      A Major Problem With The Resplandy Paper

      Resplandy et al. Part 2

    3. Re:Theory vs. data by Jane+Q.+Public · · Score: 3, Informative

      A relatively steady 2-3mm or less per year (in most parts of the world) would be max 180mm, or 18cm over 60 years.

      Most people, at most beaches, would not even notice this difference over that great a time period. In fact it is indistinguishable in comparison photographs even on certain Florida beaches which are well-known to be subsiding in addition to any ocean rise.

      Just FYI, I have noticed over a period of years that this "Angel" person has often been an opinionated, agressive, and mean-spirited arguer. My best suggestion is that he/she is probably not worth your time.

  2. Re:China will rescue them. by kenwd0elq · · Score: 5, Informative

    Actually, China isn't "re-developing low lying islands".. The Chinese are devastating and covering up living coral atolls by dredging in order to CREATE islands, in order to claim sovereignty over vast stretches of international water and to fortify those artificial islands to prevent or restrict commerce through the South China Sea. The Chinese don't care about islands; they care about dominance.

  3. Your link proves him right by SuperKendall · · Score: 5, Informative

    If you read your own link, you'll find since 1862 sea level has risen about 0.25 feet. That is hardly anything, and again, if you look at the data you posted it has actually FALLEN very slightly since 1950.

    Also doesn't the rather large jump around 1950 with no other rise since kind of speak to the measurement method having changed?

    --
    "There is more worth loving than we have strength to love." - Brian Jay Stanley
  4. Re: old story by ShanghaiBill · · Score: 5, Informative

    Yes I understood that they were all going to the US at some point.

    Mostly yes. But for different reasons. The "sea level rise" may be a problem someday, but for now sea levels are rising about 4mm per year, which may be a lot after a century, but is not even noticeable so far.

    Several of their islands are contaminated with radiation from US testing, and they have a high birth rate, so the "clean" islands are getting crowded. Marshallese have a right to immigrate to America, and many of them have done so. Many settled in Arkansas, where they work growing chickens for Tyson. There is also a large group of Marshallese on the Big Island of Hawaii, where they tend to be resented by the locals for working too hard.

  5. Re:The Seas AREN'T Rising.. by ShanghaiBill · · Score: 3, Informative

    Nope. Foreigners can not buy land in the Marshall Islands.

  6. Re:My favorite is Florida by willy_me · · Score: 2, Informative

    Red tide is not brought on by climate change. Pollutants in the water (fertilizer) result in optimal conditions for red tide. One has to better manage farming practices inland to prevent the pollutants from running off into the ocean. Warmer water temperatures could also be a factor - but minor compared to the impact of pollutants.

  7. Re:Floating islands by thogard · · Score: 5, Informative

    Sand based atolls are effectively floating on slightly more sense layers and most of them are in areas where that other layer is flat. The atolls dissolve on one side and get built up on the other by a mix of consistent ocean currents and prevailing winds. That causes the islands to creep along keeping their basic shape until they hit depression or hill on the lower layer. Depressions tends to destroy the atoll and the hills tend to split the atolls in two.

    These sinking islands are going to sink weather global warming is true or false but global warming always gets drug into conversation about them which sidelines the discussion.

  8. Re: The Seas AREN'T Rising.. by Anonymous Coward · · Score: 2, Informative

    Its possible he meant to say that the variance due to tides is much greater than the current sea level rise and therefor if the picture is taken at the appropriate time it could mask the sea level rise observed in the photo..,

  9. Re:My favorite is Florida by Anonymous Coward · · Score: 2, Informative

    Warmer waters are a precondition for dinoflagellae, the nitrates give them a food source that allows them to saturate the water when they die making it anaerobic in addition to the neurotoxic domoic acid they excrete. Both are required.
    Stop pretending you're a marine biologist who knows definitively what you're talking about when you don't. Red tide favorable conditions are indeed obviously part of climate change in some places, and you don't know how much.

    No, we don't need some layman's loose guess about which is worse, it varies from place to place and both are bad news because the result is dead zones and possibly eventually loss of species. Yes, climate change influences that.

    Lie casually again and you lose a finger.