Cretaceous sea levels

Discussion in 'Earth Science' started by sculptor, Apr 5, 2020.

  1. sculptor Valued Senior Member

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    I've found several conflicting estimates of Cretaceous sea levels.
    darned confusing
    your thoughts?
     
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  3. exchemist Valued Senior Member

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    My thoughts are: "Now how is sculptor going to try to twist this round into evidence against man-made climate change?"

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  5. sculptor Valued Senior Member

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    Well now,
    That is somewhat delusional.
    It seems rather obvious that anthropogenic atmospheric forcing should have a noticeable effect on the climate.
    Occasionally, I wonder if people who are fond of stating the obvious would tell an obese woman that she is fat.

    What I was looking for was a comparison of modern topography/elevation of shorelines and coastal plains to those of the cretaceous, incorporating an ice free, and more equable earth's climate.
    And, just how much water would be stored in the trees and soils of a temperate rainforest which would likely cover the arctic and antarctic(replacing the arctic desert). Adding in an estimation of the change in atmospheric moisture should round the information nicely.

    but alas
     
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  7. iceaura Valued Senior Member

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    Why?
    The continents have moved, since then. The ocean basins have changed shape. Entire mountain ranges have emerged. The shorelines and coastal plains are in different places, abutting different oceans. How did you plan to compare them?

    And what does "more equable" mean?
     
  8. sculptor Valued Senior Member

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    7,221
    why?
    hmmm...
    I love this earth and would know her history and moods.
     
  9. (Q) Encephaloid Martini Valued Senior Member

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    Yes, could you be any more vague?
     
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  10. iceaura Valued Senior Member

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    That hardly explains a windmill tilting project like comparing modern and ancient shorelines by "sea level".

    How were you planning to compare the Cretaceous shoreline heights with the modern ones? Were you planning to somehow match up the Cretaceous continents and oceans with "equivalent" modern ones? Calculate Cretaceous basin depths and midoceanic rises on some kind of probability distribution grounds, or ignore them?
     
  11. Xelasnave.1947 Valued Senior Member

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    Are you saying the current projected sea level rises should be looked at in the context of other factors besides those attributed to climate change?
    Alex
     
  12. iceaura Valued Senior Member

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    I'm not talking about the current sea levels at all.
    Anyone looking at them should of course include all the significant factors they can handle. Why not?
     
  13. billvon Valued Senior Member

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    A noble cause. But with your political agenda driving your understanding, there are certain things you will never be able to learn about. Which is really too bad; why choose politics over science?
     
  14. Xelasnave.1947 Valued Senior Member

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    I ask because I hear of islands in the Pacific going under at a rate which doesn't seem consistent with sea level rise and wondered if their problem may be firstly that they are sinking.
    Why not yes why not.
    Alex
     
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  15. (Q) Encephaloid Martini Valued Senior Member

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    After ten days, we still haven't seen anything about the conflicting estimates you refer? I'm assuming you're very hard a work putting all the information together so we can peruse the data and make informed opinions, yes?
     
  16. iceaura Valued Senior Member

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    30,802
    Which would have nothing to do with Cretaceous shoreline characteristics;
    Whose sea levels are impossible or useless to compare with modern shorelines anyway, because everything has moved and changed shape since then. Sculptor is just typing stuff that sounds like it might cast doubt on something to do with AGW.

    (btw: Their rate of inundation is perfectly consistent with AGW instigated sea level rise, in most cases.
    A couple are suffering from having drawn too much fresh water out from the lens under their surface, depleting their aquifer, which has caused some land sinkage in places as it has in various US locales especially in western States,
    but most of the problem is a long-predicted consequence of AGW.

    There is a common illusion or (more likely) propagandist's misrepresentation of the predicted AGW sea level rise - you can find it on this forum even in the less bizarre rightwingers' posts, sculptor's and billvon's for example - that consists of presenting either the average rise in sea level or the rise in average sea level as encompassing the threat from AGW sea level boosting. As those following the literature and research have always known, the serious inundation threat comes from the often nonlinear effects of warming sea level rise on peak storm surge heights, peak wave heights, peak tidal effects, and the like. A one cm AGW boost in local sea level can newly inundate and make newly uninhabitable land that was much higher off the former inundation level than one cm. Many low islands of the Pacific will have to be abandoned long before their land surface is below the former inundation level plus the rise in sea level - they are going to have king tides and storm surges and big waves washing right over them, saturating their soil and aquifers with salt water and flooding their houses and washing out their infrastructure, while the average sea level at the nearest shoreline is still a long way from overtopping anything.
     
    Last edited: Apr 14, 2020
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  17. Xelasnave.1947 Valued Senior Member

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    You are correct but I know this.

    First let me thank you for addressing my question.

    I did ask about the sea level predicted rise and although I forget the number that answer gave a figure that was so seemingly small I could not see why folk were so concerned.

    Perhaps you work with another number..may I ask your view and request you provide a number that you feel is reasonable.

    The thing I find most concerning is the propaganda coming from both sides really.

    Do you recall my post on the list claiming a long list of scientists had signed a letter where it was clear that was a lie and no more than propaganda.

    If the science is clear why the need to lie as it just makes folk think there is an unrelated agenda and certainly gives opponents support for claiming there is some general flaw to the proposition that all the information in support is reliable.

    To me that suggests that there should be no building etc on that land if it is vunerable to such a small change in the sea level. The fact is that land just should not be used. The small city of Lismore to the East of here is subject to flooding, it has always been subject to flooding since its foundation. The water level comes up to see the ground level shops and business in the main Street flooded to their ceilings. The cry used to be that the council should build better levies and last flood you had folk saying it was due to climate change, which weakened the AGW cause because floods go back a century and saying such was clearly propaganda of the most terrible kind, but the real issue simply is you should not build on a flood plain...
    And do they learn..absolutely not..the city was located there because in those times transport was tied to the river, but now it has no transport on it at all. Now a KLM and a half from the current CBD the land rises and there is a plateau that is a perfect place for the CBD so the smart thing to do would be relocate from the flood plain.
    And sure climate change will see heavier rain and more frequent flooding but climate change is not the problem here but building on the flood plain is and always has been.
    And when you see poor folk flooded on beach fronts all I can ask is what did you expect.
    I have no doubt but the reality is these places were always inches away from being uninhabitable and turning climate change around will not change that no more than putting up levies in Lismore changes the fact that the CBD is sitting on a flood plain...it's not that hard to work out that a plain is called a flood plain because it floods.

    Sorry to go off topic.
    I guess the thread made me realise the world changes and we need to move around to be in the best spot rather than to think we can prevent change.
    AGW is just one change we need to accommodate...Lismore needs to realise that the boats don't bring the goods these days so being a long way from the river makes total sense...leaving places that will be effected by rising sea levels makes total sense.
    Alex
     
  18. iceaura Valued Senior Member

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    30,802
    All the seriously damaging propaganda is coming from the media wing of the American fascist movement, which has taken over the Republican Party and is currently attempting to get complete control of the US government.

    There is no equivalent propaganda coming from the reality based, scientifically literate, non-Republican, liberal, or leftwing sides - any of them. There is no leftwing Fox News - there isn't even an authoritarian leftwing CNN or MSNBC, let alone a libertarian one. There is no leftwing Facebook - not even an authoritarian one. All of the leftwing intellectuals with significant followings or influence are honest and reality based, even when mistaken.

    "Both sides" in modern American politics is bullshit. Always.
    They have been inhabited, many of them, for thousands of years. They are being made uninhabitable suddenly, recently, within a century or less, by the Western industrial practice of using the atmosphere as a dumping ground for the waste products of fossil fuel combustion.

    And if you add up the number of human beings whose current and ancestral homes have always been inches away from being uninhabitable in some way, you'll get into ten digits pretty quickly.
    Assuming we can. If we let it hit as hard as it's coming there is a very good chance that accommodating it will be a fond but unrealistic daydream we used to have.
     
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  19. Xelasnave.1947 Valued Senior Member

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    I would like to think so but it would be naive to think we don't have some nutters on board and unfortunately when some folk think left wing they only think of the rat bags which I find less than helpful.

    I don't think America has a monopoly on the bullshit in politics.

    True but you can't expect that cities that grew like London for example and early inhabitants somehow made habitable can get away from the fundamental problem that its location is not ideal.

    Things can only change as cultures change. Like Lismore it needs to relocate rather than think things can go on the same way never to recognise the location is just plain wrong.

    And cities grew up on rivers for the same reason Lismore was close to the river.. trade..but we have trucks now and that changes everything however folk will hang on to the past and refuse to keep up with reality.
    The pollution certainly worries me and we can't get rid of it but that does not mean we shouldn't minimise it.
    Look at the waste with oil..V8 cars, racing etc. Oil has its place just like coal and I think the first issue to address is eliminating the waste and conserving these assets. Fortunately we have electric cars coming available but the problem is they don't make a gutsy V8 sound and therefore don't appeal to the idiots who do not see cars as transport but as toys and status symbols. It is interesting to note that the main reason Tesla cars are becoming fashionable is because they can out drag a flash BMW..how sad is that and how telling of the dumb mentality that is the main reason pollution is not managed far better.
    Sure but what does that prove?
    Once being on a river was important but today it's about being close to a major highway if you think about it.
    Just because we had to live on flood plains in the past does not mean we must live that way in a world that has changed.
    I suspect that we won't change things until folk get a different approach to wasting energy.
    Imagine the improvement if folk did not waste energy, that cars be limited to a small engine capacity, look at the damn 4wds that never see a dirt road.
    My car is 1600 cc I changed from a 1200 cc manual to an auto only because of my legs issues. I thought I needed those extra cc s but in reflection a 1200 auto would do the job...if I was in the city and did not have to do these 700klm trips on a regular basis a 500 cc car would be fine in the city for me..And I sit along the high end BMW and the non off road 4wd in the stopped traffic and think...mmm even at 1000 rpm idle each are pumping 1000 times their engine capacity say 3 or 4 Lt. each minute... The un necessary difference adds up...but you know one must have a BMW as a first car to show your importance and the Missus must have a 4wd to run the kids to school and do the shopping...and of course visit their house at night and you notice every room in the house has the light on and there are garden lights front and rear...and I bet you ask them about climate change and they are all for solar panels..in fact they often have them.
    But only to sell energy to the grid.

    Nothing will change in attitude I feel but you know they are so concerned so they fly overseas for their holidays.

    Now me I don't care if the low lying areas are flooded and if where I am becomes drought prone as I will simply relocate ...
    If the house burns down in the mean time the next one will be underground. The key is realising change is the one constant and managing change seperates the men from the boys.

    Alex
    Alex
     
  20. iceaura Valued Senior Member

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    They don't have mass followings, or significant national influence.
    The rightwing nutters do.
    If the expected or "most likely" or best supported prognostications of the AGW researchers pan out as evidence and theory says they will, you will have plenty of company in your relocation efforts - several hundred million fellow "relocaters", or as they are often called these days "refugees", will be looking for a new place to live by the time this century closes.

    If they are lucky.

    Although through procrastination and dithering we have lost our chance to curb AGW enough to prevent major disasters, we can still mitigate AGW somewhat - enough to reduce that refugee number to a more manageable one, say, hold on to a fairly productive agricultural system and a working industrial economy, give the wildlife some time to adjust - but not by trying to negotiate compromises with "both sides". The bad guys have to be fought, and their side beaten.
     
  21. sculptor Valued Senior Member

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    7,221
    I ask open ended questions because I do not want primary school responses.
     
  22. Xelasnave.1947 Valued Senior Member

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    Well I think we will need luck.

    You see when I was only 20 we were concerned about pollution from vehicles just from the view point of the air becoming of poorer quality and even back then you had folk saying the world would end in 12 years.

    Even though I still raced moto cross which was hypocritical.

    My mate was also a racer but full on about folk should drive small cars but he totally flipped and started importing big cars from the US saying the best approach was to use up the oil as fast as possible.

    I see a future where cities are under domes and food is grown hydroponically and all species that we can't eat are no more and folk will be worrying about something new.

    So to a degree I am becoming a little like my mate in so far as I think let it happen and the sooner the better so we can develop even better methods to destroy the place.

    Alex
     
  23. (Q) Encephaloid Martini Valued Senior Member

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    Maybe you should try upgrading your open ended questions to beyond primary school grade?
     
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