Wednesday 4 February 2009

Hans Erren vs the people of Shishmaref

In his blog on the Dutch newspaper Volkskrant called klimaathype (i suppose this needs no translation), skeptic Hans Erren presents his views on Global Warming.

Shismaref Shishmaref Sarichef global warming
Erren's latest post is comparing the Dutch Wadden Sea island Vlieland with the Alaskan island Sarichef where the Inuït Village Shishmaref is located. The island received some attention in Holland because of the movie The Last Days of Shishmaref by director Jan Louter, which tells the story of the islanders who fear they'll have to move to the mainland as their island slowly gets swallowed by the sea.

The Wadden Islands (or Frisian Islands) including Vlieland, are a chain of islands in the North of Holland and continuïng in Germany until the border with Denmark.

Basically the islands are sandplates sticking out above sea level, and therefore the tide has great influence on their shorelines. Mankind has done efforts to decrease erosion in order to slow down natural processes, but of course the process itself cannot be fully halted.

At the erosion side, the islands shrink while at the other side progradation makes them grow. As a result the shorelines are ever moving and in Dutch we say the islands are "walking". Because of erosion, in 1736 on Vlieland an entire village (Westeynde) was swallowed by the sea.

Erren compares the present events at Sarichef, a small (7 km long) sandy island in Alaska, to what has happened to Vlieland in the past.

Sarichef island also knows a lot of erosion, to such an extent the islanders are worried their entire village might disappear in the nearby future as erosion is taking away a couple of metres of land every year.

There are several different natural causes for this erosion, yet some effects can be linked to global warming. The arctic area in recent times has known a fast increase in temperatures, causing the permafrost to melt, making the soil more vulnerable for erosion. Above that, increased temperatures result in less sea-ice, ice which serves as a natural storm surge.

The AAAS-website has a longer article on the subject : In Arctic Alaska, the Warming Climate Threatens an Ancient Culture


On the Volkskrantblog, Hans Erren writes (my translation) :

Hans Erren global warming Shishmaref Sarichef
Hans Erren
Sarichef is a Wadden Island in Alaska, comparable to Vlieland. For the inhabitants from the village Shismaref the same fate is waiting as the inhabitants of Westeynde. They only just started living there and aren't used to walking islands, therefore they blame climate change.

That's why they don't want that the island to 'disappear in the sea".
Is the Island disappearing ? Well, no. It's just moving a little bit. At the South-West side, there's a strong growth, just like on Vlieland.

Of course, even without AGW there'd be erosion on Sarichef, that much is true. But as mentioned above, global warming probably increases erosion. Yet even if AGW is a hoax, there are two very clear problems with Erren's words. Erren writes :
  • They only just started living there and aren't used to walking islands
It's clear Erren wants to make his readers think the islanders simply aren't aware of natural processes on such islands. What he doesn't mention is the area has been inhabited for hundreds of years already. All that time, the 'walking-island-effect' has occured, and the inhabitants know the phenomena.

  • Is the island disappearing ? Well, no, it's just moving a little bit. At the South West Side, there's a strong land-growth, just like on Vlieland.
in the comments section, Erren is asked for some more information and a source for his claim. His answer is nothing but an attempt to distract attention from the question :
All i can do is point out the similarity in geometry between Vlieland and Sarichef. For the Wadden Islands there's this map by Gerbrand Gaaff (...) Progradation at the South, Erosion at the North Side.
Clearly, he doesn't even get close to answering.

I spent an hour to find a source which supports Erren's statement but all i could find was info (p.ex. in Living with the coast of Alaska by Mason et al.) which says the island doesn't grow on the South-East as Erren states, but actually is lenghtening to the North-East

Meanwhile on the volkskrantblog, Erren again is asked for sources. Given the red herring in his first reply, I'm rather curious now what he's going to say.

6 comments:

  1. wait and see jules.

    Thank you for bringing my weblog under the attention of a larger community.

    ReplyDelete
  2. all you've given so far is a red herring and an update of your post (after being asked for souces) with more maps of ... Vlieland.

    I am still waiting, that's for sure...

    ReplyDelete
  3. wait and see jules.

    Thank you for bringing my weblog under the attention of a larger community.


    That's your answer for the evidence you were asked for to back up a comment that you have already made?

    I don't mean to be rude but, my god, in Australia we have a word for that... it's called wanking, and you would be called a wanker. No insult is worse.

    Either back yourself with evidence, or admit to incautiousness with your statement, but don't wank-on mate!

    ReplyDelete
  4. update :

    On the volkskrantblog i asked three questions which Erren answered to. Well sort of.

    my questions were :
    1) why do you think the inhabitants aren't used to walking islands ?
    2) do you have a quantification for growth and erosion ?
    3) a question for a little more eplanation on what Erren means by "permafrost melt is a local phenomena"


    Erren answers :
    1) on which grounds do you conclude the Inuit have a better knowledge on the subject than the people of Vlieland
    ( of course i made no such claim J.)

    2) answer : erosion : 1m a year on the North side. Erren found no data on progradation but compares landsat images.
    (user jlaan asks whether the Landsat images can be compared, as they are taken in different seasons and there's no indication on the tide (high/low) etc.)

    3) Erren : permafrost melt, due to modern construction techniques, is highest where houses have been built. This doens't meant he island is disappearing. Since 1974, due to a shift in PDO, storm intensity decreased, and therefore erosion decreased also.
    Erren simply ignores the possible link between AGW and increased erosion due to reasons mentioned in my post : permafrost melt and less protection from sea-ice

    Personnaly i find Erren's answers unsatisfactory

    ReplyDelete
  5. 1)The only prehistoric settlements that remain in the area are simply the ones that weren't washed into the sea so it's not planning, it's luck.

    2) Patience, I am not forgetting you, I am working on the quantification, I have not come across anything in the literature, so I have to do it myself. Of course if you have any numbers, don't hesitate to provide references.

    3)
    The take home message is:
    The greatest storm erosion occured in the 50's and 70's during a cold PDO phase. During the current warm PDO phase the storm erosion rate decreased.

    Erosion is greatest on the sea front to local melting permafrost around concrete foundations.

    So:
    a) Greater erosion rates in Shismaref town is indeed man-made but not by CO2 from far away but from local melt around concrete foundations.
    b) Erosion rates are less in a warm PDO phase
    c) There is no scientific evidence that erosion rates are increasing.

    ReplyDelete
  6. 1) is not even close to an answer

    2) you should've made a quantification BEFORE making you original post in which you claim the island is just walking.

    3) not even close to answering the other possible factors that could play a role.

    i'm still not satisfied...

    ReplyDelete