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Re: THE Volcano Thread Pt. 2

Unread postPosted: Sat 14 Apr 2018, 23:29:00
by dohboi
https://www.radionz.co.nz/international ... t-for-help

An Ambae community leader is pleading for the Vanuatu government to act quickly to evacuate residents who are in dire straits with the island's volcano spewing ash and gas.

Due to a constant heavy ash fall which has covered food gardens, grass on which animals feed and contaminated water supplies, the government says there is no other way but to evacuate all inhabitants...


more here:

https://phys.org/news/2018-04-vanuatu-i ... rupts.html

“All crops and trees are destroyed by the ash fall. There is no food. All water storage is destroyed by the sand and acid rain. There is no water."
https://twitter.com/janinekrippner/stat ... 7988820995


http://dailypost.vu/news/ash-fall-destr ... 546a0.html

Re: THE Volcano Thread Pt. 2

Unread postPosted: Sun 15 Apr 2018, 12:42:47
by ROCKMAN
dohboi - "...unless you have evidence that there has been some increase in their activity recently." That's the problem: no one is monitoring undersea volcanic activity. The Mid-Atlantic Ridge might be putting out 5X as much material into the ocean then it was 10 years ago. Or just 20% as much as then.

Here's a Science article from 2016. The problem is that this project covers less then 1% of the subsea volcanic activity:

"WILLIAM WILCOCK had been monitoring the volcano for months as the tremors around its base grew more frequent. Such swarms of small quakes might, under normal circumstances, have stirred thoughts of alerting the authorities and perhaps warning residents nearby. But these weren’t normal circumstances. This volcano was 1.5 kilometres under the sea, and its nearest neighbours were a lot of tube worms and crabs.

Wilcock is a marine geophysicist at the University of Washington, Seattle, and part of an ambitious project to explore the 70 per cent of our planet’s surface that is invisible beneath the waves. Known as the Ocean Observatories Initiative, its aim is to wire up sections of the sea floor to an array of sensors that will continuously monitor in real time everything down there – from chemistry and currents to the ebb and flow of life. Wilcock’s volcano, Axial seamount some 500 kilometres off the US Pacific north-west coast, was laced with more cables than the average suburban neighbourhood.

Volcanoes exemplify our ignorance of the deep ocean. We didn’t know underwater volcanoes encircled the planet until the 1950s, when cartographer Marie Tharp mapped the mid-Atlantic ridge. Using echo-sounding data from research cruises, she showed that this long rise in the Atlantic sea floor – extending, she would later find, almost from pole to pole – wasn’t one ridge, but two bisected by a valley."

Re: THE Volcano Thread Pt. 2

Unread postPosted: Sun 15 Apr 2018, 13:08:32
by rockdoc123
Evidence from paleomagnetics suggest that seafloor spreading doesn't progress at a constant rate but instead has periods when the spreading rate is much faster. The fact that we seem to be seeing increased volcanic activity around plate margins (ring of fire) may be indicative that sea floor spreading rates have increased. Increased activity at spreading centres would go hand in hand with faster spreading rates.

Re: THE Volcano Thread Pt. 2

Unread postPosted: Sun 15 Apr 2018, 17:42:18
by dolanbaker
I would imagine that as the Earth has a fairly constant diameter that only slowly increases as space matter arrives, then any rapid sea floor spreading on one side would have to be countered by subduction elsewhere. So which comes first, the spreading increasing pressure forcing subduction, or subduction reducing pressure and easing spreading?

Re: THE Volcano Thread Pt. 2

Unread postPosted: Sun 15 Apr 2018, 18:12:00
by rockdoc123
The actual mechanisms are still debated somewhat but most believe circulation in the mantle coupled with density spreading of new oceanic crust from the higher ridges towards the subduction zones is the main culprit. The subducted slab is melted and contributes to volcanoes through uprising magma, the majority being assimilated into the mantle and redistributed at the ocean ridges.

Re: THE Volcano Thread Pt. 2

Unread postPosted: Mon 16 Apr 2018, 11:28:05
by ROCKMAN
Donlan - All good questions. But I doubt those dynamics can be measured in the span of a human lifetime. And worse: I doubt anyone is making much effort to measure "the big picture".

Re: THE Volcano Thread Pt. 2

Unread postPosted: Wed 25 Apr 2018, 11:03:24
by dohboi
Ambae, one of the islands of the Vanuatu archipelago, has a volcano- Monaro- that has always been active but is now destroying the habitat.

https://www.theguardian.com/world/2018/ ... t-on-ambae


A landslide and flash flood on the Vanuatu island of Ambae is complicating evacuation efforts, with as many as 800 people now sheltering in emergency relief centres.

Ambae Island is home to 11,000 people, and for the second time in six months Manaro volcano on top of Mount Lombenben has started rumbling, spewing torrents of ash, gas and rocks from its crater. The debris is causing breathing and health problems, and threatening livelihoods by burying vegetable plots and crops.

The government has declared a three-month state of emergency while it works with non-governmental organisations to safely evacuate the island and secure new homes for displaced islanders who may never be able to return.

Acting prime minister Jean Pierre Nirua said Vanuatu was the most vulnerable country in the world to natural disasters, and was currently stretched by responding to the clean-up of last month’s cyclone Hola and the unfolding Ambae emergency.

According to the Vanuatu meteorology and geohazards department the volcano remains at level three, with a danger zone surrounding the cone of three kilometres.

Due to eruption activity the cone of the volcano had widened, resulting in ash fall, gas, and acid rain, as well as a heightened risk of landslides and flash floods.

Re: THE Volcano Thread Pt. 2

Unread postPosted: Thu 26 Apr 2018, 00:45:01
by Plantagenet
Small eruptions continuing on Sentaru Volcano here on Java

Cheers

Re: THE Volcano Thread Pt. 2

Unread postPosted: Fri 04 May 2018, 08:50:59
by dohboi
https://www.cnn.com/2018/05/04/us/kilau ... index.html

Hawaii's Kilauea volcano erupts, prompting mandatory evacuations

(Video includes lava spewing out of a road in a suburban development.)

Re: THE Volcano Thread Pt. 2

Unread postPosted: Fri 04 May 2018, 11:59:58
by Plantagenet
The last eruption in this area east of Kiluea was in the 1960s---and it went on for months. All the current houses in this area have been built since this time. Whoever was in charge of residential zoning should be prosecuted --- it was very irresponsible to allow houses to be built in this area.

It will be interesting to see if this current eruption is a repeat of the 1960s eruption, or if Kiluea is doing something new.

Cheers!

Image
Its crazy to allow houses to be built anywhere along the east rift zone of Kiluea---the whole area is at extreme risk for lava flows

Re: THE Volcano Thread Pt. 2

Unread postPosted: Fri 04 May 2018, 14:07:43
by dohboi
Sooo, you're for strong government regulation and against people making money? :-D

Re: THE Volcano Thread Pt. 2

Unread postPosted: Fri 04 May 2018, 14:44:55
by Newfie
Being down here in the Carribean I’ve gotten a whole new appreciation of volcanoes. This coming week we will be passing “Kick em Jenny” an underwater volcano, an island in the making. A couple of months ago it was active and the exclusion zone was increased to about 5 miles. But it’s gone quiet again so the exclusion zone is back down to about a half mile. Lava won’t leap out and grab you, but gasses will reduce the water density to the point where your ship will sink.

Having fun.

Re: THE Volcano Thread Pt. 2

Unread postPosted: Fri 04 May 2018, 16:26:32
by Tanada
Plantagenet wrote:The last eruption in this area east of Kiluea was in the 1960s---and it went on for months. All the current houses in this area have been built since this time. Whoever was in charge of residential zoning should be prosecuted --- it was very irresponsible to allow houses to be built in this area.

It will be interesting to see if this current eruption is a repeat of the 1960s eruption, or if Kiluea is doing something new.

Cheers!

Image
Its crazy to allow houses to be built anywhere along the east rift zone of Kiluea---the whole area is at extreme risk for lava flows


I disagree completely. I think people wanting to build in the area should be required to sign a declaration of understanding to show they know the risks and any time a new person buys or leases property there they should also have to sign said declaration. Other than that I think adults have the right to do stupid stuff, otherwise you would need 24/7 security following everyone everywhere to keep them from getting boo-boo's and then you would need more security to watch over the first security and so on ad infinitum. You either have to accept people are adults, or you have to treat them as infants, there is no middle ground.

Re: THE Volcano Thread Pt. 2

Unread postPosted: Fri 04 May 2018, 17:04:54
by Newfie
Tanada,
That’s a tough choice. If you accept them as infants then you are having them followed by infants. On the other hand if you accept them as adults you assume they will not do stupid things and hurt others, unlikely.

If we treat all folks as adults then we need to accept they will off themselves on a regular basis and if they off someone else then they have proven to not be adult and need to be removed themselves.

I’m OK with that, but I doubt it will get popular approval.

Re: THE Volcano Thread Pt. 2

Unread postPosted: Fri 04 May 2018, 17:20:56
by Plantagenet
dohboi wrote:Sooo, you're for strong government regulation and against people making money?


Yes, I'm against people building homes in areas where volcanic eruptions occur frequently. This doesn't preclude the use of the land for other purposes that can make money, such as agriculture.

Part of my scientific work has involved making scientific studies of volcanic hazards, seismic hazards, flood hazards, etc.

Scientists are pretty good at delineating areas on the ground that are at clear risk from natural hazards, and at predicting the statistical likelihood of a recurrence of the natural hazard. This information is typically compiled in "hazard zone maps" that are made available to the public and are officially transmitted to local government officials.

However, its not up to the scientists to set zoning laws----its up to local governments. IMHO homes, hospitals, schools etc. shouldn't be built in areas that have a significant likelihood of being destroyed every 50-100 years of so by natural hazards but I understand that some property rights extremists like yourself will put profits over people and will fight any zoning restrictions.

Image
lava hazard map for the island of Hawaii

Cheers!

Re: THE Volcano Thread Pt. 2

Unread postPosted: Fri 04 May 2018, 17:35:06
by Newfie
We visited Monserrat where the town was built on an old ash flow, it was the level ground. They evacuated the southern half of the island. The North half is very steep, they had to build much new housing there. There is nonreal town anymore, just folks living here and there.

Then we went to St Pierre on Martinique. May 8, 1902 pyroclastic explosion took out entire town of 30,000. Then in August that year a second explosion killed another 3-4,000, one additional town and some relief workers in the old town. Looking at the geography you would think the town was protected, it wasn’t. But the sides of the volcano are full of agricultural fields and the area is being built back up. St Pierre is now about 5,000 but there are many more in newer towns and scattered about the general area.

Re: THE Volcano Thread Pt. 2

Unread postPosted: Fri 04 May 2018, 21:17:43
by Plantagenet
Newfie wrote:We visited Monserrat where the town was built on an old ash flow, it was the level ground. They evacuated the southern half of the island. The North half is very steep, they had to build much new housing there. There is nonreal town anymore, just folks living here and there.


Thats very interesting.

I went to Montserrat for a couple of weeks as a consultant during the beginning of the eruption crisis in 1995, and I arrived just after a pyroclastic flow killed a number of local people who were going back into the red zone to tend crops. There was a posh British ex-pat community living in cliffside villas along the west coast, and they put me up in a nice cliffside villa with a grand ocean view. At that time they had already mostly evacuated the town, although the British volcano response team was working out of a funky old hotel on the north edge of the town near the beach. The town had a well known recording studio that reggae artists liked to use, but the town was largely shut down although just lightly covered by ash when I was there. Now the buildings are pretty much buried by mudflows, ash and PFs I hear. The locals had mostly already been relocated to big hot stuffy brown canvas british issued military tents in a couple of sites on the north side when I was there, with most looking at being evacuated to England.

Image
Sounds like the tents are gone, but things still aren't back to normal on what is left of Montserrat.


Cheers!

Re: THE Volcano Thread Pt. 2

Unread postPosted: Fri 04 May 2018, 21:36:25
by dohboi
"property rights extremists like yourself "

moi??

I don't give a flying fig about property rights. Perhaps this was addressed to T?

I just found it interesting that, in this case, you accept that people should be told not to make money if that might end up hurting someone. This is the essence of the philosophy of an American liberal, and I hadn't pegged you for one of those.

Anyway, things seem to be getting worse:

https://www.cnn.com/us/live-news/hawaii ... -eruption/


A fifth volcanic vent has opened in Leilani Estates

Thousands without power after 6.9 quake

Earthquake triggers landslides along Hawaii's coast

Re: THE Volcano Thread Pt. 2

Unread postPosted: Sat 05 May 2018, 06:22:07
by dohboi
And now...Alaska:

https://www.cnn.com/2018/05/05/us/alask ... index.html

I wasn't even aware that Alaska had volcanoes! D'oh!

Makes sense, though, being in the 'ring of fire.'

Re: THE Volcano Thread Pt. 2

Unread postPosted: Sat 05 May 2018, 09:24:13
by Newfie
Plant,

Take this with a grain of salt, stuff I got from the old guy who showed us around the island. Let’s hope I’ve got the numbers straight.

Pre eruption there were about 12,000 in the island.
Now there are about 5,000 remaining. So 7,000 emigrated to the UK and elsewhere.

Wrong! 10,800 emigrated. If the 5,000 remaining only 1,200 are from Montserrat, the balance, 3,800, are immigrants from Haiti, DR, and Guyana, places even less fortunate than Montserrat. They come there to establish citizenship which takes 6 years and then enables them to move to the UK.

Or so I’ve been told. I don’t really know the truth but it sounds reasonable although one has to ask why the government would allow such a thing. I suppose there are reasons.

It does lead one to ask when they should just abandon the entire island, turn it into a nature park.

Newfoundland struggles with these decisions.

http://www.cbc.ca/news/canada/newfoundl ... -1.4560571

In follow up to the above the most recent vote was 100% in favor of resettlement.