MARINERS-L Archives

From: "David Andrews" <>
Subject: [Mar] Nuclear Subs & Global Warming
Date: Sun, 27 Aug 2000 11:57:19 +0100

The sad fate of the Kursk has no implications for global warming. Global
warming is not due to man-made heat; if it is caused by man then it's due
to more natural heat (which is on a scale vastly greater than than anything
we make) being retained by increased carbon dioxide in the atmosphere.


The Earth intercepts about 100,000,000,000 MW of solar (light and heat)
radiation. Solar heating panels (which get about 10% of that) are reckoned
to be good for about 100 W per sq.metre directly face on to bright
sunlight.

And that's before you also take into account the heat generated within the
earth by decay of naturally occuring radioactive elements within the Earth
itself - I can't find a figure for this at the mo' but remember that all
vulcanism (ordinary eruptions as well as the Krakatoa type events) is as a
result of a fraction of that heat.



By contrast he press say that each reactor on the Kursk is a PWR of about
70 to 90 MW (that may not be accurate but it can't be far out; you wouldn't
get the Sizewell-B PWR (3000 MW) in a submarine unless its hull was the
size of the Queen Mary).

When a reactor shuts down the fission product decay heat is initially 7% of
the previous full power figure, falling to 4% at one minute, 0.7 % at 1
day, and 0.07% at 1 year. And even if the reactors didn't shut down (which
they undoubtedly did, it would have been very obvious if they hadn't) but
had remained at power, no reactor can run for ever; to keep running they
have to be re-fuelled. No power reactor could run at high power for more
than few years without re-fuelling; if it's not re-fuelled it is incapable
sustaining a chain reaction just as a boiler can't raise steam once the
coal runs out.


The problem that should concern everybody with Kursk and Kosmolets, and
presumably Thresher and Scorpion, is radioactive contamination released
when the cores corrode.


[But I must have a go at the standard long half-life quotes beloved of
many; yes Iodine-129 has a half-life of 16 million years so what ?
Everyone's body contains of the order of a milligramme of Potassium-40,
that has a half-life of a thousand-million years. You'd have to ingest a
vast amount of either to do you any harm as very little of it would decay
and irradiate you in your lifetime 70-odd years. Far better worry about
Strontium-90 which has a half-life of 28 years, (funny how you never hear
about that one these days)].


regards Dave Andrews

ex-Central Electricity Generating Board / Nuclear Electric Training Centre
(1980-84)

This thread:

• [Mar] Nuclear Subs & Global Warming by "David Andrews" <>