[ExI] Refreezing the Arctic ocean
hkeithhenson at gmail.com
Mon Feb 8 17:51:34 UTC 2010
On another list someone wrote
> The bigger problem right now is solar insolation during polar summers. This
> is the Arctic problem in the immediate term and a intermediate problem for
> the West Antarctic Ice Sheet. A blue water Arctic is starting, I don't want
> to use the words "chain reaction" (it's not a nuclear process), but least
> non-linear warming (oceanic).
Scaled down by a factor of 25, say a 2.5-3 inch pipe 50 feet long, the
heat pipe I analyzed would suck out 4 kW with the same delta T for the
heat exchanger. The Arctic isn't as cold as the Antarctic, but at
least 5 months of the year it is cold enough to make this work. A kWh
is 3600 kJ. So such a heat pipe would freeze 4*3600/333kJ/kg, ~43 kg
of water per hour.
After 5 months, that would be ~160000 kg of ice, or 160 tonnes, or 160
cubic meters. This would be a cylinder of ice ~16 m high by ~4
meters. Such a slender ratio would have to be examined for stability
(sinking weight on a cable perhaps). The interior would be at -15 C,
which seems to me that it would likely last without much loss till the
next winter, but this would need to be calculated. In 5 years the
block would be 8 meters across.
I don't know what would be the optimum heat pipe size or spacing, or
how spacing could be maintained, but this is the general idea of how
to refreeze the Arctic ocean. What it would be doing is to raise the
effective temperature in the Arctic during the coldest part of the
year, making the radiation into space higher.
I also don't know if this is economically feasible, or even desirable
(shipping). But this is the kind of thought that would go into an
engineering solution if anyone cared to look in this direction.
The West Antarctic Ice Sheet is made for the trick of freezing it to bedrock
>>this motion would stop if the glacier was frozen to the bedrock.
> Then, it's not a glacier.
It's not going to stop them moving entirely, just slow them down. Ice
is still plastic.
(mondo snip to another post)
>> FACT: All glaciers are retreating, many already gone. Glaciers are the
>> source of the
>> majority of the world's fresh water, directly or indirectly. ...
> Sure, Keith compares them to farm land.
Only for the point that the area of glaciers isn't orders of magnitude
larger than the area humans have massively affected. This is an
economic argument: if humans were really were desperate, we could
afford to pin glaciers and slow them down.
It's not just melting in sunlight. Glaciers flow down to lower and
warmer altitudes and into the sea where they melt. Getting dark
particulates out of the air by switching away from coal and dirty
burning engines would also help slow down melting.
>> All we can do is band-aid what we can and live with the pain,
I have been aware since the early 70s. Dr Peter Vajk and I were
nearly thrown out of a Limits to Growth conference in 1975 for having
the gall to suggest there might be a way out of the problem. Now, 35
years later, and perhaps too late, space based solar power is finally
getting serious attention.
They still are not taking a systems approach which tells you that
chemical exhaust velocity is not enough for low cost energy. But the
methods,for example, air breathing part way up and laser heated
hydrogen above that, are obvious if you go back to the basic physics.
Of course, economically it only works for a large traffic model.
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