CurtAdams@aol.com wrote:
>
> In a message dated 3/26/00 6:16:15 AM Pacific Standard Time,
> neptune@mars.superlink.net writes:
>
> Re flooding the rift valley:
>
> > On the practical side, what do you [anyone] think about the impact of this
> > poor man's macroengineering project? Would it be a net gain or loss for
> > people living there and in adjoining regions? What would its impact be in
> > global climate and ecology?
>
> For the local humans, generally good: they'd get ocean access, a milder
> climate, and more rain. Some farmland and such gets flooded at the bottom,
> but it's probably replaceable. Be a real headache keeping the pollution down,
> though.
>
> For the local ecology or paleontology, it's a catastrophe. Desert critters do
> very poorly in shallow seas and anything interesting gets covered up or eaten
> :-/
>
> The rift valley isn't large enough to affect the whole world's climate or
> ecology
> directly.
>
> >Michael S. Lorrey retroman@turbont.net wrote:
>
> >> The only thing separating the Rift Valley from being flooded is about
> >> 100 meters
> >> of rock on the shore of the Red Sea. I could fix that situation with a
> >> couple dozen pounds of C4.
>
> I'm not convinced that blowing a (relatively) small hole in the rock barrier
> will
> suffice to flood the valley. The flow rate would have to exceed evaporation
> from the entire flooded valley, and that's a lot. There are several places
> where large river flows still don't suffice to raise a sea even close to sea
> level
> (e.g., the Caspian Sea) Flooding the rift valley is at most a mesoscale
> project,
> but I think you'd need more than a few dozen pounds of conventional explosive.
The Caspian sea is limited a) by the fact the Russians dammed off and
redirected one of its main tributaries, and b) it is supplied by a
limited water shed.
Compared to the size of the Rift Valley, the Indian Ocean is a virtually
infinite watershed.
The sea level of the Indian ocean will not change, it will have a
constant head pressure. Since the slope on the valley side of the
separator has a significant drop to it, cutting one channel ten feet
across from the sea to the slope would cause a significantly high flow
and velocity, equal to a constant spring flood flow. The erosion will
cause the channel to widen. Granted that it needs to get bigger to get
the Valley to equal sea level, but that isn't necessary, you aren't
trying to make it a port. There is currently a small stream flowing into
the valley from the sea, but the water seeps through the rock that
blocks it off, but you are right, that small amount of flow that is
existing evaporates off within a few miles. Making a large enough flow
to cause significant erosion will create a self expanding channel.
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