alt.energy.renewable

On Apr 13, 1:54=A0pm, David Moss
wrote:
> On Sat, 12 Apr 2008 02:32:20 -0700, Fran wrote:
> > On Apr 12, 6:26=A0pm, David Moss wrot=
e:
> >> On Sat, 12 Apr 2008 01:19:19 -0700, Fran wrote:
> >> > He's right about it being comaparatively benign *in the present
> >> > tense*. Human activity is prejudicing that.
>
> >> Seems to me that even in the worst case scenario some people are going
> >> to have to pack up their bags and move somewhere else.
>
> > In the *worst case scenario*, David, there weill be a lot more to worry
> > about than having to move. Some of the modelling for 550 PPM by 2050 has=

> > temperatures up 10 degrees C by 2100 and possibly rises in sea levels of=

> > 6-7 metres. I regard that as improbable, but if it came to that those
> > who were alive to witness it would surely be cursing those who failed to=

> > do everything conceivable and viable to arrest it now.
>
> >> I've done that quite
> >> a few times, whats the problem?
>
> > I don't suppose moving the world's ports and the connected
> > infrastructure and residences to places deemed outside the possible
> > disruption many years before it actually occurred would generate any
> > logistical, economic or political issues ...
>
> > Fran
>
> I've seen quite a few photos of steps leading into the sea, or ancient
> cities being dug out of the sand. It is a mistake to think the
> infrastructure we pride ourselves so much on having built will last more
> than a few centuries no matter what we do.

Yes, but as in all things, the speed at which change is driven
is pertinent. Having to phase change infrastructure over a cycle
lasting centuries is nothing like the burden of having to do it over
20-50 years. Given sufficient time and orderly procedures, we can
adapt. The point is that the precise amount of time and the size of
the necessary response remains unclear, and to fall short invites
disaster.

http://www.acecrc.org.au/uploaded/117/797532_01ib03_sealevelgeneral_07.pdf

This shows some modelling not for the worst case scenario but a faily
midrange one -- where sea level rises are 0.5 metres by 2100. Note
that surge and tide events that should occur once every few decades
now occur in the thousands or ten thousand (depending on location) in
that time.

Hansen speaks in his worst case scenario of one metre sea level rises
per 20 years or about 5 metres by 2100. If ocean heating and
associated thermal transport and increased albedo continue to disrupt
the Greenland and West Antarctic ice sheets as they are now, then even
this rate of sea level rise *might* be optimistic, and 6-7 metres by
2075 is not entirely excluded.

The question remains -- where does one put the ports and the
supporting infrastructure when one is in a hurry? You can't just wheel
them back.

And what of what economists call 'the hinterland' but which in
geographical practice should probably be called the 'juxta'land -- the
land along the coasts of the world which are typically the most
densely populated and often have some of the most agriculturally
valuable land? Are they to be abandoned or protected? Either way, it
won't be cheap.

> The sea is not going to rise
> seven metres overnight. Its not goint to do it in a few days, weeks,
> months or years. It isn't even going to do it in a few decades, even in
> the worst case scenario.

Yes, in the worst case scenario, it well might. And even being
optimistic, it probably will within 150 years.

> If the worst comes to pass we will simply
> rebuild our ports a bit further up the beach as they need replacing.
>
> Personally I think peak oil is a far greater threat to human welfare than
> global warming.
>

You raise this as if this were an opposing to thing to worry about
when it's part and parcel of the same problem -- another reason to act
swiftly in the here and now on reducing the fossil fuel concentration
in energy.

Fran