The globe's first climate refugees

[Stella_Omega]

The evacuation of the Carteret Islands have begun. ... king tides have washed away their crops and rising sea levels poisoned those that remain with salt. The people have been forced to move.

Just sayin, yanno.

 

[JAMESBJOHNSON]

Nice try.

According to the articles I found, sea levels in the area have risen 6-8 millimeters over the last 7-8 years. Thats about 1/3 of an inch.

The Carteret Islands are low-lying coral islands scattered around a coral created atoll. The atoll sits atop active tectonic plates that create frequent earthquakes, and coral atolls tend to sink, over time, anyway. And the inhabitants dynamite fish in the lagoon.

 

[trysail]

The 1841 sea level benchmark (centre) on the `Isle of the Dead', Tasmania. According to Antarctic explorer, Capt. Sir James Clark Ross, it marked mean sea level in 1841. Photo taken at low tide 20 Jan 2004.
Mark is 50 cm across; tidal range is less than a metre. ® John L. Daly.

http://www.john-daly.com/index.htm

 

[voluptuary_manque]

The Carterets are an atoll. Atolls form when a volcano erupts and forms an island. Then coral reefs grow around the island. As the volcanic island erodes and sinks into the crust only the top of the reef remains. Yes, the world is getting warmer and possibly the sea level is rising but it hasn't shown up on the data, yet. After all, if all the sea ice melted the ocean levels wouldn't change because ice displaces the same volume whether frozen or liquid. Elementary school physics, that.

 

[R. Richard]

The Carterets are an atoll. Atolls form when a volcano erupts and forms an island. Then coral reefs from around the island. As the volcanic island erodes and sinks into the crust only the top of the reef remains. Yes, the world is getting warmer and possibly the sea level is rising but it hasn't shown up on the data, yet. After all, if all the sea ice melted the ocean levels wouldn't change because ice displaces the same volume whether frozen or liquid. Elementary school physics, that.

Not quite. Ice floats. Thus it increases in volume [4% IIRC] as it freezes.

 

[voluptuary_manque]

Not quite. Ice floats. Thus it increases in volume [4% IIRC] as it freezes.

True, but the the increase in volume sticks up out of the water. When it melts, the volume it displaces, just like a ship, is what it weighs.

 

[DesertPirate]

Of course the fact that temperatures have dropped for the last 10 years means nothing.

 

[Katyusha]

Yes, the world is getting warmer and possibly the sea level is rising but it hasn't shown up on the data, yet. After all, if all the sea ice melted the ocean levels wouldn't change because ice displaces the same volume whether frozen or liquid. Elementary school physics, that.

Sea ice, yes. What about the land glaciers? Greenland's ice sheet? Antarctica? Those ice sheets are melting and calving and because they aren't already part of the water they do contribute to rising sea levels. Sea ice isn't the problem (in this case). It's the land-based ice that's the problem.

**I'm not looking to debate the validity of anthropomorphic climate change here, so those of you who do want to debate it don't start with me. I'm just pointing out a fallacy I saw above.

 

[voluptuary_manque]

Oh, I'm in agreement with that, but the volume of land ice thus far hasn't been sufficient to raise sea levels. I emphasize "thus far". However, as DP pointed out, the global temps peaked a while ago and have stabilized. I am in no position to debate why that might be but the data is clear. Go figure.

 

[JAMESBJOHNSON]

The real scientific evidcence points to sun-spot activity cycles.

Of course, if its true Obama will be taxing sunshine and trying to trade our sunshine to those parts of the planet that are dark.

 

[Stella_Omega]

Thanks guys, I was browsing when I saw that article.

So manque, you're saying that the land is dropping-- not the sea rising? I can easily see how that would happen, the porous tufa compacting into soil.

 

[voluptuary_manque]

Thanks guys, I was browsing when I saw that article.

So manque, you're saying that the land is dropping-- not the sea rising? I can easily see how that would happen, the porous tufa compacting into soil.

That's very possible. Look at the Hawaiian Archipelago. It starts in the southeast with the Big Island but if you follow it northwest across the ocean you see that the islands get smaller and smaller until there's nothing left but ring-reefs of coral around what used to be a volcano. I strongly suspect that the same thing is happening here. Not that it matters to the poor people involved. Either way they have to abandon their homes.

 

[R. Richard]

That's very possible. Look at the Hawaiian Archipelago. It starts in the southeast with the Big Island but if you follow it northwest across the ocean you see that the islands get smaller and smaller until there's nothing left but ring-reefs of coral around what used to be a volcano. I strongly suspect that the same thing is happening here. Not that it matters to the poor people involved. Either way they have to abandon their homes.

Interesting thought. The big island is the largest and is the site of active volcanos. In fact, perhaps every ten years there's a major eruption and the TV shows a river of lava flowing to the sea. It's an accepted geological fact that the Hawaiian islands were formed from basically one hot spot in the Pacific tectonic plate.

 

[voluptuary_manque]

Interesting thought. The big island is the largest and is the site of active volcanos. In fact, perhaps every ten years there's a major eruption and the TV shows a river of lava flowing to the sea. It's an accepted geological fact that the Hawaiian islands were formed from basically one hot spot in the Pacific tectonic plate.

Yup, and the sinking of the central island after it moves off the hot spot to leave an atoll is standard geological dogma.

 

[Darkniciad]

Fairly sure that I've seen this island mentioned on a Discovery program at some point, and that it is indeed both sinking and eroding from the tides, rather than suffering from rising sea levels.

Can't name the program or be absolutely certain that I have the right island, but everything seems to click in my head.

 

[amicus]

Heh! Seems like the tide has changed!

AmicusVeritas

 

[slyc_willie]

From what I've read, I can only say VM's spot on. While the sea level is rising marginally, the geographic features of the island are what's causing the apparent sinking.

I'm of the mind that sea levels on this planet rise and fall in cycles. While there may be some impact caused by humans, it is invariably tempered by the natural cycles of the planet we live on.

 

[R. Richard]

Yup, and the sinking of the central island after it moves off the hot spot to leave an atoll is standard geological dogma.

It makes sense. The core of an active volcano is lava, supported by pressures from the core of the earth. The volcano grows until the weight of the core equals the pressur from below. Once an island moves off a 'hot spot' or the hot spot begins to fill with solid, rather than molten lava, there remains less force to support the solid lava core. It would seem likely that the solid lava core would then sink over time.

 

[voluptuary_manque]

It makes sense. The core of an active volcano is lava, supported by pressures from the core of the earth. The volcano grows until the weight of the core equals the pressur from below. Once an island moves off a 'hot spot' or the hot spot begins to fill with solid, rather than molten lava, there remains less force to support the solid lava core. It would seem likely that the solid lava core would then sink over time.

A textbook couldn't have put it better. Well done, that man.

 

[DesertPirate]

Yup, and the sinking of the central island after it moves off the hot spot to leave an atoll is standard geological dogma.

I heard that some of atols are the rim of the crater after it has collapsed.

 

[voluptuary_manque]

I heard that some of atols are the rim of the crater after it has collapsed.

I hadn't heard that but I see no reason to disbelieve it.