Tuvalu - What is the real picture?

[BLAST FROM THE PAST]

Sea level rises have accellerated recently adding to the 17cm rise for the 20th century. The main culprit for the speed up in rise is meltwater which , in 05' outstripped the amount due to thermal expansion.

The coolists who see a 'cooling ocean' must have a lot of work to do to explain away the accelleration when the cooler oceans should be contracting (suggesting even more meltwater input)

Maybe you should show me where you look for your data BFTP as I'm sure it's have me less concerned than the places I plunder at present (NASA,NSIDC,NOAA et-al).

Here's the latest from the N.S.

http://www.newscientist.com/article/mg2032...we-thought.html

Ok GW

Then how do we explain this

http://news.bbc.co.uk/1/hi/sci/tech/5076322.stm

The tiny country of Tuvalu is not cooperating with global warming models. In the early 1990s, scientists warned that the Pacific coral atoll of nine islands - only 12 feet above sea level at its highest point - would vanish within decades, swamped by rising seas. Sea levels were supposedly rising at the rate of 1.5 inches per year.

However, new measurements show that sea levels have fallen 2.5 inches since that time. Similar sea-level declines have been recorded in Nauru and the Solomon Islands. (London Telegraph, 6 Aug 2000)

In 2003, Nils-Axel Mörner and his colleagues (see below) pub-

lished a well-documented paper showing that sea levels in the

Maldives have fallen in the last 30 years.

"The Maldives in the central Indian Ocean consist of some 1,200

individual islands grouped in about 20 larger atolls," says Mörner.

In-as-much as the islands rise only three to seven feet above sea

level, they have been condemned by the IPCC to flooding in the

near future.

Mörner disagrees with this scenario. "In our study of the coastal

dynamics and the geomorphology of the shores," writes Mörner,

"we were unable to detect any traces of a recent sea level rise.

On the contrary, we found quite clear morphological indications

of a recent fall in sea level."

Mörner’s group found that sea levels stood about 60 cm higher

around A.D. 1150 than today, and more recently, about 30 cm

higher than today.

"From the shape and freshness," Mörner says, "one would assume

that the sea level fall took place in the last 50 years, or so."

"In the IPCC scenarios," Mörner concludes, "the Maldives were

condemned to disappear in the near future." "Our documentation

of actual field evidence contradicts this hypothesis."

From "New perspectives for the future of the Maldives"

Nils-Axel Mörner, Michael Tooley, and Göran Possnert,

Global and Planetary Change, Vol. 40, Issues 1-2,

Jan 2004, pp 177-182

Nils-Axel Mörner, Paleogeophysics and Geodynamics,

Stockholm University, Sweden

Now it seems the graph was taken from 23 recording stations, maybe it isn't anywhere globally accurate enough. It seems some places rise as others fall?

Also I totally agree with Cap'n B, where is the acceleration? More inaccurate spin from GW? Also where are the locations of the tidal records?

BFTP

[Gray-Wolf]

http://www.sciencedaily.com/releases/2008/...80618143301.htm

I've had a peep and this is the latest research I could find on sea levels.

Tuvalu just brings forward skeptics mags and right wing U.S. commentaries/blogs. The latest 'reasonable' hit was last year, take a look

http://www.tuvaluislands.com/warming.htm

[jethro]

My understanding of Tuvalu is not so much that it is suffering sea level rises, but more that it is suffering severe over-population problems and economic crisis. The government has been trying for years to get either the USA or Japan to pay for the damage caused to the island during WWII; I think the appeals for the rest of the world to compensate them for AGW caused problems is a huge red herring.

http://www.tuvaluislands.com/news/archived.../2002-03-30.htm

http://www.ingentaconnect.com/content/bpl/...000002/art00001

[Methuselah]

My understanding of Tuvalu is not so much that it is suffering sea level rises, but more that it is suffering severe over-population problems and economic crisis. The government has been trying for years to get either the USA or Japan to pay for the damage caused to the island during WWII; I think the appeals for the rest of the world to compensate them for AGW caused problems is a huge red herring.

http://www.tuvaluislands.com/news/archived.../2002-03-30.htm

http://www.ingentaconnect.com/content/bpl/...000002/art00001

It tells me one thing, Jethro: some of the doomsayers got their predictions badly wrong.

[Chris Knight]

My understanding is that coral atolls are always witin a few metres of sea level by nature. Ancient, extinct ocean volcanoes erode, and shallow water coral species colonise the submerged fringes of the island. Eventually the volcano erodes away completely, leaving a shallow lagoon surrounded by coral islands.

Living, atoll-building coral is only present in the top few metres of tropical seas, requiring sunlight, but not too much UV, and just cool enough water temperatures to ensure that the coral polyps are the dominant organism. The living coral is neither submerged too deep, nor exposed by tidal action.

Diminishing sea levels, or rising sea beds expose the reefs, the exposed corals die, and erosion takes place, creating sand and a habitat for water-, air-, and animal-borne plant seeds and spores to germinate. Sand binds together with roots of vegetation and rain produces freshwater water tables. Wind and tides build up more sand, birds and rafted animals occupy the various ecological niches. Coral eaters, such as parrot fish, produce even more sand, and occasional storms and tsunamis both strip away and deposit more debris on the islands.

Eventually man discovers the island, and settles there. If the island provides enough for a large population to develop such as in Tuvalu, the balance between people and nature becomes even more precarious. Freshwater aquifers are overdrawn, and become brackish or saline. Sand is used to produce concrete for roads, sea defences, and buildings, and the physical structure of the islands becomes more prone to erosion. Pollution and overfishing kills the local corals, and rapidly the source of the replenishing coral sand disappears, and in time the islands die, and disappear into the ocean.

[osmposm]

Thank you very much for that excellent, clear summary of the nature of atolls, Chris; it that brought together threads of things I half-knew, and several I didn't.

I thought this was an interesting and pretty balanced piece for laymen on the state of Tuvalu from Nature in 2006: http://www.scidev.net/uploads/File//pdffil...ture/tuvalu.pdf

I was particularly taken with the quote from Bill Mitchell, manager of Australia's NTC (National Tidal Centre): “We’re going to be waiting around for a fair while before our estimates of sea-level rise become statistically meaningful,” he says. “Everyone presses you to give a number. We put a vast amount of effort into telling people that you should not be using numbers yet.”

There are several interesting papers on South Pacific sea levels linked here that confirm that position: http://www.bom.gov.au/pacificsealevel/presentations.shtml

Once again I am very taken with a quote (from a 2003 paper): "On average, global relative mean sea levels have risen between 1 and 2 mm/year over the last century and there has not been a detectable acceleration due to climate change."

There are just too many variables involved in too short a period of measurements to enable us conclude yet just what is going on; it's no wonder there are so many arguments about it. But Jethro, I tend to agree with you: at the moment the AGW issue is pretty much a big red herring.

It would be ironic (and very educative) if all the Tuvaluans were eventually moved off the islands as existence had become untenable; and as a result of the removal of humans, the islands re-established a natural dynamic balance, and flourished once more at a few metres ASL - whatever slow changes there were in that level, and however they were caused.

[BLAST FROM THE PAST]

Thansk for some pretty informative and very relevant posts folks.

Paul no worries, ta for PM.

Fred

[Pingo]

Tuvalu will always be near sea level due to the nature of its bedrock. Same withthe Ganges delta. The delta will always flood every now and then, but then miraculously redeem itself and new settlements will appear, because lo and behold living in fertile areas and flood plains are fertile areas.

Nothing to see here, please AGWers avert your gaze and stop rubbernecking, it's what has always happened.

[oldsnowywizard]

i thought islands like Tuvalu were impacted more by earthquakes and seismic conditions which meant that the islands itself can rise.. i think i saw a programme saying something about dead coral being found up on the beaches well away from current sea heights. Just thought i would add that little one..

[Pingo]

i thought islands like Tuvalu were impacted more by earthquakes and seismic conditions which meant that the islands itself can rise.. i think i saw a programme saying something about dead coral being found up on the beaches well away from current sea heights. Just thought i would add that little one..

It's nice Old Snowy to meet someone who has researched the history of Pacific islands properly