
Why did the Tasmanians Stop Eating Fish? - pg
http://scienceblogs.com/gregladen/2010/08/why_did_the_tasmanians_stop_ea.php
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dejb
You'd have to think that the land hunters would have been the ones with both
the incentive and the means to enforce a cultural taboo on fishing. They might
not want a whole other profession of people training with weapons all day.

I could also imagine there might have been a time when there was a group who
fished which where eventually wiped out. The non-fishing group may have
demonized them so much that when they got rid of them, they just weren't able
to overcome the view that fishing was inherently evil. This is, of course,
just speculation.

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ggchappell
Can anyone explain this sentence?

> Did they just become inundated by the sea, perhaps living as the people of
> XXX live today, on a very low island in the middle of the sea, ....

There is a reference to an endnote at the end of the sentence, but the note
talks about tidal waves, not this mysterious "XXX".

~~~
btilly
There are several possible values of XXX. The most likely is the Maldives, see
<http://en.wikipedia.org/wiki/Maldives>. Note that the whole country is
seeking a place to relocate in the event of sea level rising due to global
warming. If global warming continues according to current projections, the
entire country will be under water at some point in the next century.

~~~
bugsy
Pretty much any coral atoll will do. Kiribati comes to mind for example. The
problem with these examples is that coral atolls sink naturally, a coral atoll
is what is left after the volcano it was around has finished sinking into the
ocean. It has nothing whatsoever to do with rising sea levels. Everyone
worldwide who is among the millions living on coral atolls today is facing
"rising oceans" and salivating over possible global warming payouts from
carbon tax funds. But their atolls are sinking regardless of whether carbon
dioxide levels are creating warming. In fact, higher carbon dioxide levels
being absorbed into the oceans (which is happening) create accelerated coral
growth and offset some of the sinking effects. You might as well say that more
carbon dioxide is needed as it can save these atolls. But in reality nothing
can save them, all atolls sink. Building roads on them and driving to and fro
is known to accelerate the sinking as well.

~~~
btilly
The fact that a coral atoll will sink naturally on its own in due time doesn't
change the fact that a modest rise in sea level would sink lots of atolls all
over the world.

About your carbon dioxide non-sequitur, as carbon dioxide gets absorbed in the
ocean it forms carbonic acid, which changes ph levels. A relative modest
change in ph level causes problems for animals that use calcium carbonate as a
building material. (You cannot lay down calcium carbonate structures when the
water is even slightly acidic.) A prime example is coral, and ocean
acidification has already been blamed for large coral die-offs in the great
barrier reef of Australia.

Therefore whether or not global warming is man-made, more carbon dioxide is
the last thing that coral reefs need right now.

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bugsy
We know that the oceans are the largest global sinks for CO2. Not only
carbonic acid is formed, you conveniently forget to mention that it
disseminates as a combination of dissolved CO2, HCO3, CO3 and the H2CO3 you
mention. The CO3, carbonate, is essential in the formation of coral atolls.
Without carbon dioxide sinking and forming CO3, coral could not form. The
relative mixture of what results depends on a number of factors of which ocean
temperature is the primary one. The Orr article, which is the original source
on acidification leading to coral loss, reports on a theoretical computer
model about what might happen in the future and is not based on any actual
observational data that this has happened to coral in the past or is happening
now. Coral losses in the 1998 season were due to el niño conditions and are
not related to acidification. Regarding computer models of global climate and
global ecosystem interdynamics it is telling that none so far have succeeded
in predicting anything beyond random chance. Because of this, it is not
reasonable to assume that the computer model simulations that have yet to be
compared against real life are the first ones that will finally be correct.

~~~
btilly
Let's see what happens with each of those reactions.

CO2 + H20 + CaCO3 yields Ca(HCO3)2 + energy. This reaction turns calcium
carbonate into calcium bicarbonate, which is water soluble and floats off.

HC03 is unstable, and only exists in a stable form when combined with a metal
ion. Such as happened above in a reaction that came out of destroying calcium
carbonate.

C03 is unstable, and only exists in a stable form when combined with a metal
ion. The supply of such metal ions at the present time is relatively stable
and is uncorrelated with temperature.

And when you dissolve CO2 in H2O, there is an equilibrium balance between C02
+ H2O and H2CO3.

So half the compounds you list don't exist on their own. And even high school
chemistry is enough to tell you that adding CO2 to a marine environment with
lots of CaCO3 is going to have an inevitable net effect of dissolving some of
the CaCO3 that is there.

You'd have been better off falling back on the fact that the oceans are large,
and that ph is locally more affected by ocean currents and upwelling from the
deep ocean than it is by anything in the atmosphere. Because it is true that
the yearly variation at any given location exceeds the total rise in the 20th
century, and also exceeds the projected rise in the 21st century. (That said,
the problem appears at the peaks, and high peaks can cause die-offs even
though ph levels spend most of their time in a good range.)

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bdr
Why doesn't Paul Graham have an iPhone?

