[semi OT] Mankind capable of destroying all life on earth?
Hardy Hestert
In the introduction they talked about our blue planet, life since
billions of years and, for the first time in history, mankind being able
to end it all.
That's not quite exact, I thought, they were not able to sterilize the
planet. Of couse we were, and are still, able to easily kill all of
mankind and pretty much every mammal on earth, but what about about the
depths of the oceans, the submarine volcanic ecosystems, supposedly the
cradle of earth's very first lifeforms? What about hardy (I like that
word :) bacteria and our dear friends, the cockroaches?
Nowadays the nuclear arsenals are much bigger, not to mention the
biological and chemical killers our great minds have created. But I
think it's still an interesting question. What would be the last
strongholds (including those made by man) of life on earth, and would we
be able to destroy them all? And how to destroy them?
Is mankind able to completely sterilize earth?
Hardy
James Nicoll
Yes, but not using the devices you mention, the nuclear part of
which would scarcely suffice to set California on fire. Disease is too
is too species specific (1) and the Earth is Very Big, too big to done
in with mere chemical weapons.
If we developed a collective death wise the best route would be
to dump as many greenhouse gases into the atmosphere as possible in the
hopes of triggering a runaway wet hot greenhouse effect.
--
"Frankly, Captain, I feel interstellar diplomacy is out of our
depth."
"Ah, hence the nuclear weapons."
Hardy Hestert
Greenhouse effect? Now that's one suggestion I didn't expect at all. How
hot could you get this planet forcing a greenhouse effect? Honestly I
can't imagine that it would even get hot enough to extinguish all live
on the surface. Too hot for anything to survive in the polar regions or
on the highest mountains?
And I think it would be really hard to crack those submarine volcanic
ecosystems. Heat doesn't seem to be such a big problem for them and
that's some pretty damn big oceans if you try to poison them so badly
that nothing could survive.
Leif Magnar Kj|nn|y
Hardy Hestert <hes...@t-online.de> wrote:
>James Nicoll schrieb:
>>
>> If we developed a collective death wise the best route would be
>> to dump as many greenhouse gases into the atmosphere as possible in the
>> hopes of triggering a runaway wet hot greenhouse effect.
>>
>> --
>> "Frankly, Captain, I feel interstellar diplomacy is out of our
>> depth."
>> "Ah, hence the nuclear weapons."
>
>Greenhouse effect? Now that's one suggestion I didn't expect at all. How
>hot could you get this planet forcing a greenhouse effect?
Push enough crap into the atmosphere and it could end up like Venus.
"Enough" would probably have to be rather a lot, though. I'd guesstimate
it would take a concerted high-tech effort over a long time to actually
bring it about.
>And I think it would be really hard to crack those submarine volcanic
>ecosystems. Heat doesn't seem to be such a big problem for them and
>that's some pretty damn big oceans if you try to poison them so badly
>that nothing could survive.
Bring mean surface temperatures to several hundred degrees Celsius and
the oceans will eventually vaporize.
--
Leif Kj{\o}nn{\o}y | "Its habit of getting up late you'll agree
www.pvv.org/~leifmk| That it carries too far, when I say
Math geek and gamer| That it frequently breakfasts at five-o'clock tea,
GURPS, Harn, CORPS | And dines on the following day." (Carroll)
James Nicoll
>hot could you get this planet forcing a greenhouse effect? Honestly I
>can't imagine that it would even get hot enough to extinguish all live
>on the surface. Too hot for anything to survive in the polar regions or
>on the highest mountains?
The thing is, Earth is apparently only about ten million km
from the inner edge of the habitable zone for the sun, on the brink,
in geological time, of going run away greenhouse as it is.
What happens to planets like Earth or Venus 3 billion years ago
is that the temperature goes up, some of the ocean evaporates, which
raises the temperature a bit so more water evaporates and so on. You
get to a point where the planet resembles the inside of a pressure
cooker fairly quickly. Then the cold trap keeping H2O from reaching
the top of the atmosphere goes away and UV begins cracking the water
into H and O2. The H escapes. Meanwhile, carbon sequestered in the
crust is cooked free and the lack of water contributes to the behavior
of the crust changing (I am not sure if Earth could get the same kind of
global surfacing volcanism Venus has had at least once, though).
You end up with almost no water and a surface hot enough to melt
lead. The last refuge of life is up in the clouds.
>And I think it would be really hard to crack those submarine volcanic
>ecosystems. Heat doesn't seem to be such a big problem for them and
>that's some pretty damn big oceans if you try to poison them so badly
>that nothing could survive.
In a run away greenhouse, the oceans boil away. Look at Venus.
Steve Hilberg
>Greenhouse effect? Now that's one suggestion I didn't expect at all. How
>hot could you get this planet forcing a greenhouse effect? Honestly I
>can't imagine that it would even get hot enough to extinguish all live
>on the surface. Too hot for anything to survive in the polar regions or
>on the highest mountains?
>And I think it would be really hard to crack those submarine volcanic
>ecosystems. Heat doesn't seem to be such a big problem for them and
>that's some pretty damn big oceans if you try to poison them so badly
>that nothing could survive.
Considering it's hot enough to melt lead on the surface of Venus, it would
seem that most life on Earth would not be able to survive that either....
--
Steve Hilberg <Necromancer> CITES Workstation Services Group
<hil...@uiuc.edu> KB9TEV
Member, APAGear I don't even know what CITES stands
http://www.apagear.org for, so I don't speak for them.
-----------------------------------------------------------------------------
"As we were forged we shall return, perhaps some day. | VNV Nation,
I will remember you and wonder who we were." | "Further"
Mary K. Kuhner
>> to dump as many greenhouse gases into the atmosphere as possible in the
>> hopes of triggering a runaway wet hot greenhouse effect.
>hot could you get this planet forcing a greenhouse effect? Honestly I
>can't imagine that it would even get hot enough to extinguish all live
>on the surface. Too hot for anything to survive in the polar regions or
>on the highest mountains?
Well, Venus is that hot. It's closer to the sun, but not
proportionately closer, and the excess heat is attributed to a vicious
greenhouse effect. Possibly the Earth could be heated to that
level (about 800 degrees F, as I recall, which will kill even
hot-springs bacteria). You could try the gas-pumping factories
in _Arrival_, though you'd need an awful lot of them.
>And I think it would be really hard to crack those submarine volcanic
>ecosystems. Heat doesn't seem to be such a big problem for them and
>that's some pretty damn big oceans if you try to poison them so badly
>that nothing could survive.
Even harder to reach would be the deep groundwater ecosystems.
Someone drilled two miles down into the Columbia Shield rock
formation and found bacteria living off, if I recall correctly,
sulfur or hydrogen reactions. Two miles of rock is pretty good
insulation. The 800 degrees might eventually succeed, or
might eventually kill the water cycle that keeps this area
moist. Lesser degrees of heating, enough to wipe out all larger
surface organisms, probably would go unnoticed down there.
My suggestion would be to go out to the asteroid belt, start
capturing big honking rocks and bombarding with them. Not one or
two dinosaur-killers, but a continual stream of them. If you
pounded the same place, could you rupture the crust?
But it's actually very hard to wipe out life. The best attempt
in Earth's history was made by the first photosynthesizers.
They started releasing toxic free oxygen and really screwed
up the environment, poisoning the vast majority of species. But
life not only survived but adapted in two different ways. There
are still a lot of anaerobes who have managed to insulate themselves
from the oxygen menace. And there are actually critters, ourselves
included, that have become completely dependent on the poisonous
stuff and couldn't live without it.
Unless you freeze the planet solid or raise it above the boiling
point of water, remove the entire atmosphere, or completely
ruin the crust, I think (bacterial) life is here to stay.
Mary Kuhner mkku...@eskimo.com
James Nicoll
Mary K. Kuhner <mkku...@kingman.genetics.washington.edu> wrote:
>Hardy Hestert <hes...@t-online.de> wrote:
>>James Nicoll schrieb:
>
>>> If we developed a collective death wise the best route would be
>>> to dump as many greenhouse gases into the atmosphere as possible in the
>>> hopes of triggering a runaway wet hot greenhouse effect.
>
>>Greenhouse effect? Now that's one suggestion I didn't expect at all. How
>>hot could you get this planet forcing a greenhouse effect? Honestly I
>>can't imagine that it would even get hot enough to extinguish all live
>>on the surface. Too hot for anything to survive in the polar regions or
>>on the highest mountains?
>
>Well, Venus is that hot. It's closer to the sun, but not
>proportionately closer, and the excess heat is attributed to a vicious
>greenhouse effect. Possibly the Earth could be heated to that
>level (about 800 degrees F, as I recall, which will kill even
>hot-springs bacteria). You could try the gas-pumping factories
>in _Arrival_, though you'd need an awful lot of them.
Yup. I did not say it would be easy.
>
>Unless you freeze the planet solid or raise it above the boiling
>point of water, remove the entire atmosphere, or completely
>ruin the crust, I think (bacterial) life is here to stay.
Freezing isn't going to kill the deep bacteria until the
Earth's core stops being a source of heat, which should be some time.
David Dyer-Bennet
No.
I don't think we're anywhere close.
Technical civilization, essentially certain (the capability, I mean)
IMHO.
Humanity, pretty likely.
All mammals, pretty likely.
All vertebrates, pretty likely.
All woody plants, pretty likely.
All insects, not very likely.
All multicellular creatures, not very likely at all.
Never mind the bacteria and other little guys.
--
David Dyer-Bennet, dd...@dd-b.net / http://www.dd-b.net/dd-b/
John Dyer-Bennet 1915-2002 Memorial Site http://john.dyer-bennet.net
Dragaera mailing lists, see http://dragaera.info
Hardy Hestert
I'm trying to get informed on the Runaway Greenhouse effect and that
Molten Lead Venus Scenario. A problem here seems to be that many
articles on that topic obviously follow a political agenda concerning
greenhouse gas emissions, either being overly simplistic Greenpeace
horror scenarios or appeasements from oil/economy lobbyists.
For my taste the venus comparision is often being uttered a little too
easily. (We know how much the media love to talk about Armageddon
scenarios, like all those billions of asteroids that could hit earth
every day.) Please correct me if I'm wrong (which I could very well be),
but isn't the incoming energy (sunlight) inversely proportional to the
square of the distance to the sun? That means that venus at 0,7 AU has
twice the earth's energy input per square meter. I think for a
greenhouse effect that's one major difference. On the other hand earth's
slightly stronger gravity provides higher atmospheric pressure. And
there's surely a lot of other factors to be considered. For me the
barrier you have to cross on earth to turn a greenhouse effect into a
venusian runaway greenhouse effect seems to be pretty high. I'm not
saying it's impossible, but you'd really have to push it...
However, sterilizing earth by triggering a runaway greenhouse effect
seems to inevitably be a long term project. Probably mankind would be
extinct long before the point of no return is reached. But then who'd
keep the greenhouse gas generators running?
Finally... remember the question is if mankind IS (not WILL EVER BE)
capable of sterilizing Earth. Right now, still more out of intuition
than out of knowledge, I'd say "no". Given enough time we can build a
bomb to literally blow it away so we wouldn't have to bother with
greenhouse strategies.
Hardy
Timothy McDaniel
"All"? Among posters here, I think Keith at Polarnet would lose his
job but enough of the locals ought to remember the old ways that he
might survive. I don't think Tuna, Texas, would rate any nukes, or
for that matter Alice Springs, Papua New Guinea, or Mali, or even
significant chunks of most continents.
Fire off every nuke at every plausible target in the world and
billions would still survive the strike. If there were global warming
or nuclear winter, things would get really grim, but I would expect
many millions of survivors.
>and pretty much every mammal on earth
"Pretty much every mammal"? Rodents and lagomorphs? Puh-lease.
>Nowadays the nuclear arsenals are much bigger
According to http://www.brook.edu/FP/PROJECTS/NUCWCOST/50.HTM , the
peak year for the US was 1966, with 32,193 warheads. The 2002 number
is 10,600.
Cue a long flamewar about the effects of nuclear war.
(A flamewar. How appropriate.)
--
Tim McDaniel, tm...@panix.com; tm...@us.ibm.com is my work address
James Nicoll
Hardy Hestert
> >ecosystems. Heat doesn't seem to be such a big problem for them and
> >that's some pretty damn big oceans if you try to poison them so badly
> >that nothing could survive.
>
> Even harder to reach would be the deep groundwater ecosystems.
> Someone drilled two miles down into the Columbia Shield rock
> formation and found bacteria living off, if I recall correctly,
> sulfur or hydrogen reactions. Two miles of rock is pretty good
> insulation. The 800 degrees might eventually succeed, or
> might eventually kill the water cycle that keeps this area
> moist. Lesser degrees of heating, enough to wipe out all larger
> surface organisms, probably would go unnoticed down there.
Deep groundwater ecosystems. Good one. Thanks, I'd like to keep
believing that we're not (yet) able to sterilize this world.
Hardy Hestert
About that nuclear strike... there may be less warheads now, but we
could quickly build a few thousand more, the fissionable material
doesn't disappear tht quickly. Also among those 10,600 warheads we have
now there's surely some state-of-the-art big ones which make the '66
models look like firecrackers. If we then also release all those
viruses, poisons and what-the-hell-do-I-know I think we should be able
to eliminate (at least) mankind. You can also do something against rain
forests, plankton and other green stuff to create an oxigen problem.
James Nicoll
Hardy Hestert <hes...@t-online.de> wrote:
>Responding to most posts in this part of the thread...
>
>I'm trying to get informed on the Runaway Greenhouse effect and that
>Molten Lead Venus Scenario. A problem here seems to be that many
>articles on that topic obviously follow a political agenda concerning
>greenhouse gas emissions, either being overly simplistic Greenpeace
>horror scenarios or appeasements from oil/economy lobbyists.
>
>For my taste the venus comparision is often being uttered a little too
>easily. (We know how much the media love to talk about Armageddon
>scenarios, like all those billions of asteroids that could hit earth
>every day.) Please correct me if I'm wrong (which I could very well be),
>but isn't the incoming energy (sunlight) inversely proportional to the
>square of the distance to the sun? That means that venus at 0,7 AU has
>twice the earth's energy input per square meter. I think for a
>greenhouse effect that's one major difference.
Remember that the sun is continually getting brighter and would
have been only about 2/3rds as bright when Venus did the planetary teapot
thing as it is today. Boiling Venus did get more energy but only about a
third more.
As well, while Venus had to make do with CO2 and water for
greenhouse gases, we know how to make much better ones (CFCs and HCFCs).
These can have the additional benifit of destroying the ozone layer,
always a plus in these scenarios.
>On the other hand earth's
>slightly stronger gravity provides higher atmospheric pressure.
Note that itty bitty Titan manages to hang onto a 1.5 bar
atmosphere. Gravity is a bad guide to air presssure.
> And
>there's surely a lot of other factors to be considered. For me the
>barrier you have to cross on earth to turn a greenhouse effect into a
>venusian runaway greenhouse effect seems to be pretty high. I'm not
>saying it's impossible, but you'd really have to push it...
>
>However, sterilizing earth by triggering a runaway greenhouse effect
>seems to inevitably be a long term project. Probably mankind would be
>extinct long before the point of no return is reached. But then who'd
>keep the greenhouse gas generators running?
By that point we'd hopefully have reached the magic ocean surface
temperature of 27 degrees C, where the runaway effect is thought to start
taking place. Oddly, all the articles I saw that cited that temperature
then said something like 'Luckily the oceans only get as hot as 30.5 C'
from which I deduce the reporters are extraterrestrials with tickets off
world already bought.
You can go the other way as well. If you can chill the Earth to
-50 C, the albedo will be high enough to keep it there indefinitely. There's
strong evidence that this Snowball Earth scenerio occured shortly before
the Cambrian. This should do for most of the complex life, although the
bacteria will keep motoring on.
Hardy Hestert
> -50 C, the albedo will be high enough to keep it there indefinitely. There's
> strong evidence that this Snowball Earth scenerio occured shortly before
> the Cambrian. This should do for most of the complex life, although the
> bacteria will keep motoring on.
> --
> "Frankly, Captain, I feel interstellar diplomacy is out of our
> depth."
> "Ah, hence the nuclear weapons."
If the snowball cenario occured before... it didn't last ;o)
That's it for tonight.
Hardy
Earl Colby Pottinger
> Hardy Hestert <hes...@t-online.de> writes:
> >Greenhouse effect? Now that's one suggestion I didn't expect at all. How
> >hot could you get this planet forcing a greenhouse effect? Honestly I
> >can't imagine that it would even get hot enough to extinguish all live
> >on the surface. Too hot for anything to survive in the polar regions or
> >on the highest mountains?
>
> >And I think it would be really hard to crack those submarine volcanic
> >ecosystems. Heat doesn't seem to be such a big problem for them and
> >that's some pretty damn big oceans if you try to poison them so badly
> >that nothing could survive.
>
> Considering it's hot enough to melt lead on the surface of Venus, it would
> seem that most life on Earth would not be able to survive that either....
Considering that they are now talking about possible life in the upper clouds
of Venus, even that is not a sure bet anymore.
Earl Colby Pottinger
--
I make public email sent to me! Hydrogen Peroxide Rockets, RAMDISK, Cabin
Raising, Camping, BoatBuilding. What happened to the time?
http://webhome.idirect.com/~earlcp
James Nicoll
Hardy Hestert <hes...@t-online.de> wrote:
>> You can go the other way as well. If you can chill the Earth to
>> -50 C, the albedo will be high enough to keep it there indefinitely. There's
>> strong evidence that this Snowball Earth scenerio occured shortly before
>> the Cambrian. This should do for most of the complex life, although the
>> bacteria will keep motoring on.
>
>
ways to reverse the effect. With the rocks covered in glaciers
CO2 can build up and provide a greenhouse effect and if that
doesn't work the Sun will get brighter.
Mars may be stuck in a stable icebox or not. It's possible
it flips between two states, warm(er) and wet(er) vs cold, dry and
more or less airless.
Also it's possible that ice planets, like Europa, have oceans
filled to saturation with CO2 and other gases thanks to the icy crust
that locks in the gases. This could make poking holes into the oceans
quite interesting, as the pressure drops and the gases all suddenly
come out of the solution. Imagine a seltzer bottle the size of a planet...
Timothy McDaniel
Hardy Hestert <hes...@t-online.de> wrote:
>Timothy McDaniel schrieb:
>>
>> In article <3DB59D3F...@t-online.de>,
>> Hardy Hestert <hes...@t-online.de> wrote:
>> >Nowadays the nuclear arsenals are much bigger
>>
>> According to http://www.brook.edu/FP/PROJECTS/NUCWCOST/50.HTM , the
>> peak year for the US was 1966, with 32,193 warheads. The 2002 number
>> is 10,600.
>
>could quickly build a few thousand more
I was answering "nowadays".
In any event, the US hasn't built any new nuclear devices in about
twelve years, and no tritium for 14 years, says
http://nuketesting.enviroweb.org/hew/Nwfaq/Nfaq7-2.html#usa , so I'm
not sure it would be all *that* fast to resume manufacturing.
>Also among those 10,600 warheads we have now there's surely some
>state-of-the-art big ones which make the '66 models look like
>firecrackers.
http://nuketesting.enviroweb.org/hew/Nwfaq/Nfaq7-2.html#usa says that
the largest US warhead in 1998 was 1200 kt, with most being much
smaller. The Russians appear to be comparable. But the 1954 US tests
alone mostly had yields in the 6900-15000 range.
Certainly both the US and the Russians could build very high-yield
nuclear warheads within years. However, since destruction scales by
the 2/3 power of the nominal yield, larger warheads do not give as
much bang as you would think. Current thought is to have smaller-
yield devices more precisely aimed.
Charlie Stross
as <mkku...@kingman.genetics.washington.edu> declared:
> But it's actually very hard to wipe out life. The best attempt
> in Earth's history was made by the first photosynthesizers.
> They started releasing toxic free oxygen and really screwed
> up the environment, poisoning the vast majority of species. But
> life not only survived but adapted in two different ways. There
> are still a lot of anaerobes who have managed to insulate themselves
> from the oxygen menace. And there are actually critters, ourselves
> included, that have become completely dependent on the poisonous
> stuff and couldn't live without it.
There is the germ of an SF story in here. Posit this: there exist more
efficient anaerobic metabolic pathways than any that have evolved on
earth, and complex life based on these pathways is common elsewhere in
the galaxy. Some of these life forms sent out genetically engineered
weapons a long time ago, designed to poison possible rivals by turning
their atmosphere to a thin, deadly soup of oxidizing agents. Unfortunately
they never expected organisms to exist that can actually metabolize the
stuff ...
Yes, the blue-green algae are berserkers!
-- Charlie
Charlie Stross
> You can go the other way as well. If you can chill the Earth to
> -50 C, the albedo will be high enough to keep it there indefinitely. There's
> strong evidence that this Snowball Earth scenerio occured shortly before
> the Cambrian. This should do for most of the complex life, although the
> bacteria will keep motoring on.
Your chosen weapon is: paint.
To be precise, you need some silvery (high-albedo) organic liquid that
does not oxidize rapidly, and that forms a reflective monolayer on top of
water. (Maybe some kind of saturated halogenated fatty acid, tweaked for
reflectivity?) Pour several tens of megatons of this shit into the Pacific
and Atlantic and you can turn up to 70% of the earth's surface reflective
in a matter of months. If you can arrange to keep replacing it until
the temperature drops low enough to keep the polar ice caps expanding
you've won. You could drop large weighted bags of the stuff into the
deep ocean trenches, with small pores to allow the goop to leak up
towards the surface over a period of time.
As an added bonus, if it reduces oxygen exchange between the oceans and
the atmosphere this increases its lethality in the short term.
-- Charlie
Robert Sneddon
<tm...@panix.com> writes
>
>http://nuketesting.enviroweb.org/hew/Nwfaq/Nfaq7-2.html#usa says that
>the largest US warhead in 1998 was 1200 kt, with most being much
>smaller. The Russians appear to be comparable. But the 1954 US tests
>alone mostly had yields in the 6900-15000 range.
>
>Certainly both the US and the Russians could build very high-yield
>nuclear warheads within years. However, since destruction scales by
>the 2/3 power of the nominal yield, larger warheads do not give as
>much bang as you would think. Current thought is to have smaller-
>yield devices more precisely aimed.
There are also physical limits - a 10MT warhead is a big device (maybe
not as big as depicted in _Dr. Strangelove_ but not far off). The urge
for small warheads came from the MIRV strategy developed in the mid-60s
where one launcher could deliver several warheads to a geographically-
spread range of targets rather than one big boom to a single spot. If
you want something that will fit into a W-87-sized casing you accept
your max yield is limited to something like 500kT.
The Czarbomba was a freefall bomb the Russians developed back in the
50's -- its yield when tested was something like 53 MT (and it is
thought it might have been an attempt to build a 100MT bomb that
squibbed) but it took a heavily-modified bomber to carry it and the
weight severely limited the distance it could travel; I've heard it said
the bomb was the size of a Greyhound bus and twice the weight.
ObSF: A novel I once read about a secret American project which used
Saturn Vs as *seriously* heavy-lift ballistic missiles.
--
Robert Sneddon nojay (at) nojay (dot) fsnet (dot) co (dot) uk
Karl M. Syring
<snip>
> Yes, the blue-green algae are berserkers!
Very successful ones, caused havoc for a billion years. But why are they
genetically almost identical with their supposed victims? Ha, explain
that.
Karl M. Syring
Robert Sneddon
<no...@nospam.demon.co.uk> writes
[Following up to myself...]
>
> ObSF: A novel I once read about a secret American project which used
>Saturn Vs as *seriously* heavy-lift ballistic missiles.
Just remembered the title -- "Doomsday Wing". The Saturns were tipped
with multiple megatonne cobalt-enriched warheads (and launched from Very
Big underground silos). I *think* the author might have been Don
Pendleton.
William December Starr
mkku...@kingman.genetics.washington.edu (Mary K. Kuhner) said:
> Well, Venus is that hot. It's closer to the sun, but not
> proportionately closer, and the excess heat is attributed to
> a vicious greenhouse effect.
Whoops, you lost me there. What does "proportionately closer"
mean here?
-- William December Starr <wds...@panix.com>
William December Starr
Robert Sneddon <no...@nospam.demon.co.uk> said:
> The Czarbomba was a freefall bomb the Russians developed back in
> the 50's -- its yield when tested was something like 53 MT (and it
> is thought it might have been an attempt to build a 100MT bomb that
> squibbed) but it took a heavily-modified bomber to carry it and the
> weight severely limited the distance it could travel; I've heard it
> said the bomb was the size of a Greyhound bus and twice the weight.
>
> ObSF: A novel I once read about a secret American project which
> used Saturn Vs as *seriously* heavy-lift ballistic missiles.
Hmm. I wonder what the (theoretical) yield is on the biggest
(theoretical) muthah we could deliver from orbit via the space
shuttle is.
Leif Magnar Kj|nn|y
William December Starr <wds...@panix.com> wrote:
>In article <ap4cg8$sp6$1...@nntp3.u.washington.edu>,
>mkku...@kingman.genetics.washington.edu (Mary K. Kuhner) said:
>
>> Well, Venus is that hot. It's closer to the sun, but not
>> proportionately closer, and the excess heat is attributed to
>> a vicious greenhouse effect.
>
>Whoops, you lost me there. What does "proportionately closer"
>mean here?
I'm guessing it means that the temperature difference is not
directly attributable to the increased insolation.
Naive math: Since equilibrium blackbody temperature goes as the
fourth root of insolation per unit area, and insolation goes
as the inverse square of distance from the sun, a planet's
temperature should be inversely proportional to the square root
of its orbital radius. Venus at 0.72 AU should have an average
surface temperature only about 1.2 times that of Earth: About
340 Kelvin, or a mere 60-70 degrees Celsius. This, of course,
turns out not to be the case, because it ignores (among other
things) the greenhouse effect which Venus has in spades.
Robert Sneddon
<wds...@panix.com> writes
>
>Hmm. I wonder what the (theoretical) yield is on the biggest
>(theoretical) muthah we could deliver from orbit via the space
>shuttle is.
KH-11 satellites and the Hubble telescope are about as big as can be
carried by a Shuttle (that similarity is not a coincidence). They are,
guess what, about the size of a Greyhound bus, but not as heavy. With
modern weapons design capability (mostly computational) I'd guesstimate
that inside an aeroshell plus deorbiting kick motor that would fit into
the Shuttle cargo bay you might get 200MT of bang today.
James Nicoll
William December Starr <wds...@panix.com> wrote:
>In article <ap4cg8$sp6$1...@nntp3.u.washington.edu>,
>mkku...@kingman.genetics.washington.edu (Mary K. Kuhner) said:
>
>> Well, Venus is that hot. It's closer to the sun, but not
>> proportionately closer, and the excess heat is attributed to
>> a vicious greenhouse effect.
>
>Whoops, you lost me there. What does "proportionately closer"
>mean here?
It is not closer to the sun by enough to account for the
difference in temperatures seen, I think she means. If it was just
a matter of the fourth root of the difference in sunlight received,
Venus would be unpleasantly warm but not smelter-hot.
cd skogsberg
> The Czarbomba was a freefall bomb the Russians developed back in the
>50's -- its yield when tested was something like 53 MT (and it is
>thought it might have been an attempt to build a 100MT bomb that
>squibbed) [...]
My understanding was that the Czarbomba was the first two stages in
what was designed as a three-stage bomb -- in the test the third stage
was replaced with lead.
http://nuketesting.enviroweb.org/hew/Russia/TsarBomba.html
/cd
--
"A tornado is like an ex-wife. It is entirely unpredictable,
strikes without warning, and no matter what you do it's going to get
the house." -- Dan Sorenson
Mary K. Kuhner
>mkku...@kingman.genetics.washington.edu (Mary K. Kuhner) said:
>> Well, Venus is that hot. It's closer to the sun, but not
>> proportionately closer, and the excess heat is attributed to
>> a vicious greenhouse effect.
>Whoops, you lost me there. What does "proportionately closer"
>mean here?
I was trying, awkwardly, to say that I'd read that if Earth got
as much sunlight as Venus, but nothing else changed, Earth would
not be as hot as Venus is. Venus' atmosphere traps heat more
effectively than ours.
(Of course, "nothing else changed" is implausible.)
This is hazy memory of pop-science reading, though, so don't take
my word for it.
Certainly Earth, at its given distance from the sun, can be quite
a bit warmer or quite a bit cooler than it is now; we don't
understand exactly what would have to change, but since both
extremes have occured, there are clearly ways for them to occur.
As far as we know, though, there has been continuity of life
through all adventures so far. (If there had been a very early
mass-kill we might not know about it at all, or might mistake
previous-cycle fossils for early this-cycle fossils; the very
early fossil record is extremely sparse.)
Mary Kuhner mkku...@eskimo.com
lal_truckee
> CLIP
> Also among those 10,600 warheads we have
> now there's surely some state-of-the-art big ones which make the '66
> models look like firecrackers.
Nope.
James Nicoll
Turns out big warheads were a blind alley: you can make em but
they are not all that useful.
David Dyer-Bennet
> In article <m23cqy2...@gw.dd-b.net>,
> David Dyer-Bennet <dd...@dd-b.net> wrote:
> >
> >All woody plants, pretty likely.
> >
> What about buried seeds and such?
Hmmm; may not have allowed for enough of that. Depends on how long
the full-blown nuclear winter lasts. Seeds last a long time
sometimes.
David Dyer-Bennet
> In article <3DB59D3F...@t-online.de>,
> Hardy Hestert <hes...@t-online.de> wrote:
> >Of couse we were, and are still, able to easily kill all of mankind
>
> "All"? Among posters here, I think Keith at Polarnet would lose his
> job but enough of the locals ought to remember the old ways that he
> might survive. I don't think Tuna, Texas, would rate any nukes, or
> for that matter Alice Springs, Papua New Guinea, or Mali, or even
> significant chunks of most continents.
>
> Fire off every nuke at every plausible target in the world and
> billions would still survive the strike. If there were global warming
> or nuclear winter, things would get really grim, but I would expect
> many millions of survivors.
I would expect 0 large mammals surviving beyond 25 years, myself,
after an all-out nuclear war.
Mark Blunden
Because they're genetically tailored to each environment, by
reverse-engineering existing life-forms. This ensures that they can feed off
the existing biosphere.
--
Mark.
* That power would set me up above the gods!
James Nicoll
David Dyer-Bennet <dd...@dd-b.net> wrote:
>jdni...@panix.com (James Nicoll) writes:
>
>> In article <m23cqy2...@gw.dd-b.net>,
>> David Dyer-Bennet <dd...@dd-b.net> wrote:
>> >
>> >All woody plants, pretty likely.
>> >
>> What about buried seeds and such?
>
>Hmmm; may not have allowed for enough of that. Depends on how long
>the full-blown nuclear winter lasts. Seeds last a long time
>sometimes.
Yes, and the amount of nukes we can toss around aren't much
compared to the things that dinged the Yukatan and India 65 million
years ago. The Indian pockmark is apparently 600 km wide. Trees seem
to have survived both.
Keith Morrison
>>>Of couse we were, and are still, able to easily kill all of mankind
>>
>>"All"? Among posters here, I think Keith at Polarnet would lose his
>>job but enough of the locals ought to remember the old ways that he
>>might survive.
Problem is, I look out my window and there's a big plausible target
sitting there, aka the Cam Main North Warning Station. Assuming a
two-stage strike with the second involving bombers, I'm sitting on
one of the first places to go boom.
--
Keith
wth...@godzilla1.acpub.duke.edu
> Responding to most posts in this part of the thread...
>
> I'm trying to get informed on the Runaway Greenhouse effect and that
> Molten Lead Venus Scenario.
[...]
>
> For my taste the venus comparision is often being uttered a little too
> easily. (We know how much the media love to talk about Armageddon
> scenarios, like all those billions of asteroids that could hit earth
> every day.) Please correct me if I'm wrong (which I could very well be),
> but isn't the incoming energy (sunlight) inversely proportional to the
> square of the distance to the sun? That means that venus at 0,7 AU has
> twice the earth's energy input per square meter. I think for a
> greenhouse effect that's one major difference.
This is true, but because of its high albedo
Venus actually absorbs less sunlight than
the earth does. If we got all of earth's
carbon into the atmosphere without changing
the planetary albedo we'd be warmer than
Venus.
If somehow a runaway greenhouse earth had the
same albedo as Venus does we would be cooler,
but not by as much as you might think.
On the other hand earth's
> slightly stronger gravity provides higher atmospheric pressure.
Not a relevant factor here.
> However, sterilizing earth by triggering a runaway greenhouse effect
> seems to inevitably be a long term project. Probably mankind would be
> extinct long before the point of no return is reached. But then who'd
> keep the greenhouse gas generators running?
The point is that once the planet reaches a certain
threshold, though it is nowhere near as warm as Venus,
the process will continue by itself, with no further
help from us.
I don't know exactly where the threshold is (nobody
does), but a hundred times the current CO2 seems certain
to be enough. That is easily achievable. We could do
it in a thousand years, or if we put our minds to it
in a century. True, the atmosphere would be toxic
long before that point. You'd have to keep a few
thousand workers alive for a couple of decades after
the rest of the species had died.
>
> Finally... remember the question is if mankind IS (not WILL EVER BE)
> capable of sterilizing Earth. Right now, still more out of intuition
> than out of knowledge, I'd say "no".
To me the answer is clearly "yes". Don't bother
with coal and oil, oil shales have many times as
much carbon as all the coal and oil reserves we
have found, limestone an order of magnitude more yet.
Use nuclear power to liberate it.
William Hyde
EOS Department
Duke University
Craig Richardson
>Hardy Hestert <hes...@t-online.de> writes:
>> Finally... remember the question is if mankind IS (not WILL EVER BE)
>> capable of sterilizing Earth. Right now, still more out of intuition
>> than out of knowledge, I'd say "no".
>
> To me the answer is clearly "yes". Don't bother
> with coal and oil, oil shales have many times as
> much carbon as all the coal and oil reserves we
> have found, limestone an order of magnitude more yet.
> Use nuclear power to liberate it.
Thus providing a nice, albeit rather final, irony. I like it.
--Craig
--
Managing the Devil Rays is something like competing on "Iron Chef",
and having Chairman Kaga reveal a huge ziggurat of lint.
Gary Huckabay, Baseball Prospectus Online, August 21, 2002
Paul F. Dietz
> Yes, and the amount of nukes we can toss around aren't much
> compared to the things that dinged the Yukatan and India 65 million
> years ago. The Indian pockmark is apparently 600 km wide. Trees seem
> to have survived both.
>
Nothing hit India 65 million years ago. There's a huge flood
basalt there, but it started well before the K/T impact (the
iridium boundary marker is present in an intertrap layer
of sediments between flow layers.)
Paul
Keith F. Lynch
> Posit this: there exist more efficient anaerobic metabolic pathways
> than any that have evolved on earth, and complex life based on these
> pathways is common elsewhere in the galaxy. Some of these life forms
They really stink!
(Ever smelled anaerobes? They really do smell extremely vile. Remind
me not to visit their homeworld.)
--
Keith F. Lynch - k...@keithlynch.net - http://keithlynch.net/
I always welcome replies to my e-mail, postings, and web pages, but
unsolicited bulk e-mail (spam) is not acceptable. Please do not send me
HTML, "rich text," or attachments, as all such email is discarded unread.
Damien Sullivan
>
>genetically almost identical with their supposed victims? Ha, explain
>that.
They killed all their victims. We're descended from broken berserkers.
Geneticists who say otherwise are just confused by gene-sharing.
:)
-xx- Damien X-)
James Nicoll
There appears to be a 600 km by 400 km crater off the coast
of India near Bombay, about 65 million years old. It was discovered by
Sankar Chatterjee and named "Shiva".
Karl M. Syring
> Karl M. Syring wrote:
> > "Charlie Stross" <cha...@antipope.org> schrieb
> > <snip>
> >> Yes, the blue-green algae are berserkers!
> >
> > Very successful ones, caused havoc for a billion years. But why are
> > they genetically almost identical with their supposed victims? Ha,
> > explain that.
>
> Because they're genetically tailored to each environment, by
> reverse-engineering existing life-forms. This ensures that they can
feed off
> the existing biosphere.
Not good. Blue-green algae do not need anything but inorganic matter and
light. Would explain the existence of mosquitoes, though.
Karl M. Syring
Karl M. Syring
Hmm, but it means the constructors of the berserkers lost control of
their instruments. Hopefully, nobody comes to do damage assessment.
Karl M. Syring.
John Schilling
>tm...@panix.com (Timothy McDaniel) writes:
>> In article <3DB59D3F...@t-online.de>,
>> Hardy Hestert <hes...@t-online.de> wrote:
>> >Of couse we were, and are still, able to easily kill all of mankind
>> "All"? Among posters here, I think Keith at Polarnet would lose his
>> job but enough of the locals ought to remember the old ways that he
>> might survive. I don't think Tuna, Texas, would rate any nukes, or
>> for that matter Alice Springs, Papua New Guinea, or Mali, or even
>> significant chunks of most continents.
>> Fire off every nuke at every plausible target in the world and
>> billions would still survive the strike. If there were global warming
>> or nuclear winter, things would get really grim, but I would expect
>> many millions of survivors.
>I would expect 0 large mammals surviving beyond 25 years, myself,
>after an all-out nuclear war.
On what do you base this expectation?
I would expect several billion humans surviving at D+25 years, with even
odds that some of them will be building spacecraft.
Nuclear *war* is a non-starter for causing the extinction of, well,
anything. War is by definition a conflict, with each party's efforts
deliberately confouded by someone else's efforts plus the general
chaos of war. Entire cities, *lots* of cities, will be entirely
spared in the confusion.
To wipe out even the entire human race, much less "large mammals"
generally, you have to postulate cooperative efforts to that end
on a global scale. Mass suicide, not mass murder.
--
*John Schilling * "Anything worth doing, *
*Member:AIAA,NRA,ACLU,SAS,LP * is worth doing for money" *
*Chief Scientist & General Partner * -13th Rule of Acquisition *
*White Elephant Research, LLC * "There is no substitute *
*schi...@spock.usc.edu * for success" *
*661-951-9107 or 661-275-6795 * -58th Rule of Acquisition *
Chris Clayton
wth...@godzilla1.acpub.duke.edu wrote:
> Hardy Hestert <hes...@t-online.de> writes:
> >
> > Finally... remember the question is if mankind IS (not WILL EVER BE)
> > capable of sterilizing Earth. Right now, still more out of intuition
> > than out of knowledge, I'd say "no".
>
> To me the answer is clearly "yes". Don't bother
> with coal and oil, oil shales have many times as
> much carbon as all the coal and oil reserves we
> have found, limestone an order of magnitude more yet.
> Use nuclear power to liberate it.
Yeah, but just TRY to get funding for that kind of project
in the current economic environment.
--
Chris Clayton
John Schilling
>Hardy Hestert <hes...@t-online.de> writes:
>> Responding to most posts in this part of the thread...
>>
>> I'm trying to get informed on the Runaway Greenhouse effect and that
>> Molten Lead Venus Scenario.
[...]
>> However, sterilizing earth by triggering a runaway greenhouse effect
>> seems to inevitably be a long term project. Probably mankind would be
>> extinct long before the point of no return is reached. But then who'd
>> keep the greenhouse gas generators running?
> The point is that once the planet reaches a certain
> threshold, though it is nowhere near as warm as Venus,
> the process will continue by itself, with no further
> help from us.
How does the carbon get out of the lithosphere? Because Earth
did not take the Venus route in the first place, we've had four
billion years for an alternate process to put most of our carbon
well out of reach of the atmosphere, and it is not obvious to me
that the process is reversable on anything less than a geologic
timescale.
> I don't know exactly where the threshold is (nobody
> does), but a hundred times the current CO2 seems certain
> to be enough. That is easily achievable. We could do
> it in a thousand years, or if we put our minds to it
> in a century. True, the atmosphere would be toxic
> long before that point. You'd have to keep a few
> thousand workers alive for a couple of decades after
> the rest of the species had died ... Don't bother
> with coal and oil, oil shales have many times as
> much carbon as all the coal and oil reserves we
> have found, limestone an order of magnitude more yet.
> Use nuclear power to liberate it.
For a hundred time current atmospheric CO2, you need six hundred
trillion tons of limestone or a quadrillion tons of oil shale.
I'm not sure there is that much oil shale to be had. Limestone,
yes, but all the world's mining industries combined are only good
for bringing up fifty billion tons of ore per year, so you're
talking twelve thousand years of dedicated effort.
Oh, and three hundred quadrillion kilowatt-hours of electricity to break
down the limestone. That's twenty thousand years of total generation
from all sources, not just nuclear.
OK, maybe mining and power generation and the associated support
industries only occupy about 10% of the world's labor force. And
maybe we can get a runaway greenhouse effect with ten times current
atmospheric CO2 levels rather than a hundred. Maybe if we really
devoted ourselves, we really could start the process in a century
or two.
But it takes more than "a few thousand workers for a couple decades".
It takes all six billion of us for the whole time, all working the
limestone mines and CO2 "refineries" and nuclear powerplants to run
them, even at current levels of automation.
Which means that the process fails when the atmosphere gets toxic,
heck, when the climate gets nasty enough to shut down most agriculture.
We reach an equilibrium when things are sufficiently bad that the
surviving population is fully employed in keeping itself alive and
has no time for the Great Planetary Suicide Project.
We can certainly arrange a catastrophic climate change if we work at
it, and maybe if we don't. But universally lethal climate change, I
don't see that as possible with any human effort in the near future.
No Venusian infernos, sorry.
Chris Byler
wrote:
>In article <3DB59D3F...@t-online.de>,
>Hardy Hestert <hes...@t-online.de> wrote:
>>I'm watching a documentary about the Cuban Missile Crisis on German TV.
>>In the introduction they talked about our blue planet, life since
>>billions of years and, for the first time in history, mankind being able
>>to end it all.
>>
>>That's not quite exact, I thought, they were not able to sterilize the
>>planet. Of couse we were, and are still, able to easily kill all of
>>mankind and pretty much every mammal on earth, but what about about the
>>depths of the oceans, the submarine volcanic ecosystems, supposedly the
>>cradle of earth's very first lifeforms? What about hardy (I like that
>>word :) bacteria and our dear friends, the cockroaches?
>>
>>Nowadays the nuclear arsenals are much bigger, not to mention the
>>biological and chemical killers our great minds have created. But I
>>think it's still an interesting question. What would be the last
>>strongholds (including those made by man) of life on earth, and would we
>>be able to destroy them all? And how to destroy them?
>>
>>Is mankind able to completely sterilize earth?
Almost certainly not. Ask again after we develop the technology to
push the sun to the end of the main sequence a few billion years ahead
of schedule.
> Yes, but not using the devices you mention, the nuclear part of
>which would scarcely suffice to set California on fire. Disease is too
>is too species specific (1) and the Earth is Very Big, too big to done
>in with mere chemical weapons.
Most chemical weapons are species specific (e.g. nerve toxins - only
works on things with the right sort of nervous system) and/or have
short persistence, too (break down in days or weeks).
> If we developed a collective death wise the best route would be
>to dump as many greenhouse gases into the atmosphere as possible in the
>hopes of triggering a runaway wet hot greenhouse effect.
Not even close to good enough. The deep ocean won't even notice this
(and once it works on the surface it will kill off the species that
sustain it). Admittedly there is some ecological dependence on dead
bodies falling from near the surface, but some species such as the
aforementioned volcanic vent dwellers don't need that.
It would probably take something on the order of boiling the oceans
and melting the solid crust of the earth. Which would take _really_
large amounts of energy - more than you could get out of the earth's
entire supply of fissionables. You might be able to do it with
fusion, if you didn't have to screw around with deuterium and tritium
and could just fuse ordinary hydrogen. Not practical with current
technology.
--
Chris Byler cby...@vt.edu
"It is not from the benevolence of the butcher, the brewer, or the
baker that we expect our supper, but from their regard to their own
interest." -- Adam Smith, _The Wealth of Nations_
Jordan179
>
> On what do you base this expectation?
>
> I would expect several billion humans surviving at D+25 years, with even
> odds that some of them will be building spacecraft.
>
> Nuclear *war* is a non-starter for causing the extinction of, well,
> anything. War is by definition a conflict, with each party's efforts
> deliberately confouded by someone else's efforts plus the general
> chaos of war. Entire cities, *lots* of cities, will be entirely
> spared in the confusion.
>
> To wipe out even the entire human race, much less "large mammals"
> generally, you have to postulate cooperative efforts to that end
> on a global scale. Mass suicide, not mass murder.
Even if you assume a global thermonuclear exchange between America and
the Soviet Union c. 1985 (around the time of the _biggest_ nuclear
arsenals), with deliberate countervalue targetting (i.e. aiming for
cities rather than purely military targets), and assume that China,
Britain, France, Israel, and South Africa joined the party, AND assume
that many Third World cities were targetted intentionally by both
sides ... (*)
... you'd still get surviving humans, and a heck of a lot of surviving
rats. The initial exchange would kill probably half a billion to a
billion people, with the nuclear winter killing something like 90%-99%
of those who survived the initial exchange. But, here and there, you'd
get people who just happened to be far from a target and with access
to enough food and fuel to survive the year without a summer.
(Mind you, the humans would probably be living _miserably_, and many
of them would get cancer 20-30 years down the road. But they'd
survive, and breed, and thus humanity would survive).
As for rats, large populations of them can survive practically
anything. They're cunning omnivores with small food requirements and
rapid breeding rates, and they'll genetically adapt to almost any
conditions that leave the local temperature between -25 to 50 C and
enough oxygen in the atmosphere to breed. Rats are tough little
buggers.
(*) This is about the worst nuclear-war scenario imaginable in actual
history. You could probably kill a higher percent of the human race by
deliberately using a doomsday device such as a dozen or so
strontium-enhanced 100-megaton dirty bombs, but even then some people
would just happen to be out of the denser dispersal patterns. And
this, of course, is a nuclear-SUICIDE (not war) scenario.
Sincerely Yours,
Jordan
Bryan Derksen
<no...@nospam.demon.co.uk> wrote:
> The Czarbomba was a freefall bomb the Russians developed back in the
>50's -- its yield when tested was something like 53 MT (and it is
>thought it might have been an attempt to build a 100MT bomb that
>weight severely limited the distance it could travel; I've heard it said
>the bomb was the size of a Greyhound bus and twice the weight.
The Tsar Bomba didn't "squibble", it was deliberately toned down for
the test - they replaced a uranium fusion tamper with lead. Quite the
device.
David Dyer-Bennet
> David Dyer-Bennet <dd...@dd-b.net> writes:
>
> >tm...@panix.com (Timothy McDaniel) writes:
>
> >> In article <3DB59D3F...@t-online.de>,
> >> Hardy Hestert <hes...@t-online.de> wrote:
> >> >Of couse we were, and are still, able to easily kill all of mankind
>
> >> "All"? Among posters here, I think Keith at Polarnet would lose his
> >> job but enough of the locals ought to remember the old ways that he
> >> might survive. I don't think Tuna, Texas, would rate any nukes, or
> >> for that matter Alice Springs, Papua New Guinea, or Mali, or even
> >> significant chunks of most continents.
>
> >> Fire off every nuke at every plausible target in the world and
> >> billions would still survive the strike. If there were global warming
> >> or nuclear winter, things would get really grim, but I would expect
> >> many millions of survivors.
>
> >I would expect 0 large mammals surviving beyond 25 years, myself,
> >after an all-out nuclear war.
>
>
> On what do you base this expectation?
The bad shape the planet is in (little resilience, little in reserve)
plus the effects of massive particulate and CO2 emissions leading to
horrendous climate change.
> I would expect several billion humans surviving at D+25 years, with even
> odds that some of them will be building spacecraft.
Tell you what -- let's *not* deliberately run the experiment and see,
okay? I'd give this 0.0000% probability myself -- technological
civilization is a sure goner.
> Nuclear *war* is a non-starter for causing the extinction of, well,
> anything. War is by definition a conflict, with each party's efforts
> deliberately confouded by someone else's efforts plus the general
> chaos of war. Entire cities, *lots* of cities, will be entirely
> spared in the confusion.
Not directly nuked, yes. Spared, no.
> To wipe out even the entire human race, much less "large mammals"
> generally, you have to postulate cooperative efforts to that end
> on a global scale. Mass suicide, not mass murder.
Well, we'd be cooperating with the climate mechanisms of the planet,
if that's what you mean.
Nancy Lebovitz
>> anything. War is by definition a conflict, with each party's efforts
You might get extinction of some close-to-the edge species.
>> deliberately confouded by someone else's efforts plus the general
>> chaos of war. Entire cities, *lots* of cities, will be entirely
>> spared in the confusion.
>>
>> To wipe out even the entire human race, much less "large mammals"
>> generally, you have to postulate cooperative efforts to that end
>> on a global scale. Mass suicide, not mass murder.
Unfortunately, I can't exclude that possibility. I don't think the
human race has had its last murderously bad but very attractive idea.
About 20% of Cambodians were killed for no particular reason by their
own government. I wouldn't be surprised to see some country wipe out
80% or 90% of its population one of these years. (I'm not sure whether
this belief is a matter of habitual pessimism, or a feeling that as
the world gets richer, it's easier to indulge in bad ideas and the
tools for carrying them out get cheaper.)
More bleak: Making the world uninhabitable would presumably be a high
tech project, but it's interesting that modern genocides except
for the holocaust have been fairly low tech.
--
Nancy Lebovitz na...@netaxs.com www.nancybuttons.com 100 new slogans
I want to move to theory. Everything works in theory.
Hardy Hestert
This one http://nuketesting.enviroweb.org/hew/Russia/TsarBomba.html has
pictures http://nuketesting.enviroweb.org/hew/Russia/Tsarbmb.jpg
(I want one of those under the christmas tree ;o)
Del Cotter
John Schilling <schi...@spock.usc.edu> said:
>wth...@godzilla1.acpub.duke.edu writes:
>>> I'm trying to get informed on the Runaway Greenhouse effect and that
>>> Molten Lead Venus Scenario.
>>> However, sterilizing earth by triggering a runaway greenhouse effect
>>> seems to inevitably be a long term project. Probably mankind would be
>>> extinct long before the point of no return is reached. But then who'd
>>> keep the greenhouse gas generators running?
>
>> The point is that once the planet reaches a certain
>> threshold, though it is nowhere near as warm as Venus,
>> the process will continue by itself, with no further
>> help from us.
>
>How does the carbon get out of the lithosphere? Because Earth
>did not take the Venus route in the first place, we've had four
>billion years for an alternate process to put most of our carbon
>well out of reach of the atmosphere, and it is not obvious to me
>that the process is reversable on anything less than a geologic
>timescale.
What carbon? The process William is talking about, the one which Venus
underwent all those years ago, is a runaway *water* greenhouse effect.
Carbon don't enter into it.
Venus's high temperatures are maintained today by an atmosphere of
carbon dioxide, but that's only because eventually all the hydrogen
escaped.
--
. . . . Del Cotter d...@branta.demon.co.uk . . . .
JustRead:evelationSpace:GregEganQuarantine:KimStanleyRobinsonTheYearsOfR
ice&Salt:BenJeapesHisMajesty'sStarship:BrendaWCloughTheDoorsOfDeath&Life
ToRead:LoisMcMasterBujoldDiplomaticImmunity::RobertCharlesWilsonBios:Guy
wth...@godzilla6.acpub.duke.edu
> wth...@godzilla1.acpub.duke.edu writes:
>
> > The point is that once the planet reaches a certain
> > threshold, though it is nowhere near as warm as Venus,
> > the process will continue by itself, with no further
> > help from us.
>
> How does the carbon get out of the lithosphere? Because Earth
> did not take the Venus route in the first place, we've had four
> billion years for an alternate process to put most of our carbon
> well out of reach of the atmosphere,
Earth has enough carbon for 95 bars, as does Venus.
But we don't need to liberate more than a small
fraction of that for the runaway greenhouse, given that
we have plenty of H2O - the better greenhouse gas.
Heck, without even trying we've managed to add enough
CFCs to the atmosphere to make a real difference to
climate. Come to think of it, the smart thing to do
would be to ignore CO2 entirely and produce CFCs. Far
more absorbing in the IR, and not absorbed by that
pesky biosphere.
> For a hundred time current atmospheric CO2, you need six hundred
> trillion tons of limestone or a quadrillion tons of oil shale.
> I'm not sure there is that much oil shale to be had.
Here and later I'm going to assume you are right in
all your calculations.
As of 1970 the fossil fuel inventory was about eleven
times the atmospheric CO2. Shales were about eleven
thousand times. Oil shales are of course only a tiny
fraction of that.
Limestone,
> yes, but all the world's mining industries combined are only good
> for bringing up fifty billion tons of ore per year, so you're
> talking twelve thousand years of dedicated effort.
Well, we are not really trying, are we? I'd say if we
dedicated ourselves to the project we could do far
better. If we actually intended to produce a runaway
greenhouse, with little need to make economic sense,
I think we could mine much, much more. And it would help
to eliminate some of those nasty carbon sinks.
The oceans hold about sixty times as much CO2 as the
atmosphere. Warmer oceans can hold less CO2, so there's
another feedback.
>
> Oh, and three hundred quadrillion kilowatt-hours of electricity to break
> down the limestone. That's twenty thousand years of total generation
> from all sources, not just nuclear.
Now we're talking. You've more or less convinced me
we couldn't do it in a hundred years, by CO2, but I'd still
bet on a thousand.
> But it takes more than "a few thousand workers for a couple decades".
> It takes all six billion of us for the whole time, all working the
> limestone mines and CO2 "refineries" and nuclear powerplants to run
> them, even at current levels of automation.
>
>
> Which means that the process fails when the atmosphere gets toxic,
> heck, when the climate gets nasty enough to shut down most agriculture.
> We reach an equilibrium when things are sufficiently bad that the
> surviving population is fully employed in keeping itself alive and
> has no time for the Great Planetary Suicide Project.
Most of the population is gone well before the project
ends. A couple of hundred million are left running
the machinery built in phase 1.
I think some people begin to die when the atmosphere
reaches 8X.
> We can certainly arrange a catastrophic climate change if we work at
> it, and maybe if we don't. But universally lethal climate change, I
> don't see that as possible with any human effort in the near future.
> No Venusian infernos, sorry.
It's difficult - and more difficult than I thought, I
admit - but with CFCs (or some other molecule we design
for the project) I think we can do it fairly rapidly.
You've convinced me that to do it with CO2 will take
longer than I thought.
But I have faith in the Human Race. We can sterilize
this planet!
Mark Reichert
> What carbon? The process William is talking about, the one which Venus
> underwent all those years ago, is a runaway *water* greenhouse effect.
> Carbon don't enter into it.
Would this have anything to do with the current theory that the impact
that created the Moon also eliminated most of Earth's excess water?
Otherwise, Earth really would be Waterworld, and the highest forms of
life would be the Cephalopods, particular the octopi and squids.
Captain Button
Robert Sneddon <no...@nospam.demon.co.uk> wrote:
>In article <fg9zCoBA...@nojay.fsnet.co.uk>, Robert Sneddon
><no...@nospam.demon.co.uk> writes
>[Following up to myself...]
>>
>> ObSF: A novel I once read about a secret American project which used
>>Saturn Vs as *seriously* heavy-lift ballistic missiles.
>
> Just remembered the title -- "Doomsday Wing". The Saturns were tipped
>with multiple megatonne cobalt-enriched warheads (and launched from Very
>Big underground silos). I *think* the author might have been Don
>Pendleton.
I think I have a copy of this around somewhere. A rather thin book that I
have never gotten around to actually reading.
As I recall it, it was by "George Smith", and I had assumed it was the same
guy who wrote the "Venus Equilateral" stories. But I could be worng about
that.
--
American Express says I'm deceased. Boo! Consider yourself haunted.
Captain Button - but...@io.com
Robert Sneddon
<but...@io.com> writes
>In article <CQt0O0BD...@nojay.fsnet.co.uk>,
>Robert Sneddon <no...@nospam.demon.co.uk> wrote:
>>In article <fg9zCoBA...@nojay.fsnet.co.uk>, Robert Sneddon
>><no...@nospam.demon.co.uk> writes
>>[Following up to myself...]
>>
>As I recall it, it was by "George Smith",
George H. Smith -- I was conflating Pendleton with "The Guns of Terra-
Ten", his other SF masterpiece. A quick look on abebooks refreshed my
memory.
> and I had assumed it was the same
>guy who wrote the "Venus Equilateral" stories.
George O. Smith did the "Venus Equilateral" stories. George H. Smith is
not the same.
--
Robert Sneddon nojay (at) nojay (dot) fsnet (dot) co (dot) uk
Nancy Lebovitz
<wth...@godzilla6.acpub.duke.edu> wrote:
> Well, we are not really trying, are we? I'd say if we
> dedicated ourselves to the project we could do far
> better. If we actually intended to produce a runaway
> greenhouse, with little need to make economic sense,
> I think we could mine much, much more. And it would help
> to eliminate some of those nasty carbon sinks.
>
> The oceans hold about sixty times as much CO2 as the
> atmosphere. Warmer oceans can hold less CO2, so there's
> another feedback.
>
Are you sure that the project could be kept going as conditions
worsen?
Nix
> But it's actually very hard to wipe out life. The best attempt
> in Earth's history was made by the first photosynthesizers.
Even though I knew this already, it suddenly reminded me of
the short-short _Enrico Fermi and the Dead Cat_... perhaps one
of the most implausible organisms I've ever read of, and probably
the winner of the galaxy's `Least Likely to Survive' contest.
(`... and the green scum was all there was.')
--
`The tooth fairy teaches children that they can sell body parts for money.'
--- David Richerby
Nix
> Stoned koala bears drooled eucalyptus spittle in awe
> as <jdni...@panix.com> declared:
>
>> You can go the other way as well. If you can chill the Earth to
>> -50 C, the albedo will be high enough to keep it there indefinitely. There's
>> strong evidence that this Snowball Earth scenerio occured shortly before
>> the Cambrian. This should do for most of the complex life, although the
>> bacteria will keep motoring on.
>
> Your chosen weapon is: paint.
>
> To be precise, you need some silvery (high-albedo) organic liquid that
> does not oxidize rapidly, and that forms a reflective monolayer on top of
> water. (Maybe some kind of saturated halogenated fatty acid, tweaked for
> reflectivity?) Pour several tens of megatons of this shit into the Pacific
> and Atlantic and you can turn up to 70% of the earth's surface reflective
> in a matter of months. If you can arrange to keep replacing it until
That's been used, by John Barnes; this solution is used at the end of
_Mother of Storms_ (or a variant of it involving ice crystals and a
hurriedly repoisitioned comet).
In that book he gives the critical ocean-surface temperature needed to
trigger hurricane formation as 27.5C; it seems very close to the trigger
27C runaway-greenhouse temperature given elsewhere in this thread.
(I don't trust the latter figure, though; the Earth has been though
periods when it was *much* warmer than now, and while it can cope with
lots of hurricanes at sea, I doubt there was a runaway greenhouse in
e.g. the late Cretaceous, or none of us'd be here.)
Nix
> Yes, and the amount of nukes we can toss around aren't much
> compared to the things that dinged the Yukatan and India 65 million
> years ago. The Indian pockmark is apparently 600 km wide. Trees seem
> to have survived both.
Hell, *mammals* did; even proto-primates (such as they were) were around
then, and survived.
Timothy McDaniel
Mark Reichert <Mark_R...@hotmail.com> wrote:
>the octopi
Oxford University Press, at
http://www.askoxford.com/asktheexperts/faq/aboutgrammar/plurals
say
English words of Latin or Greek origin have rather unpredictable
plurals, and each one usually depends on how well established that
particular word is. It may also depend on whether the Latin or
Greek form of the plural is either easily recognizable or pleasant
to the speaker of English.
Although it is often supposed that octopi is the 'correct' plural
of octopus, and it has been in use for longer than the usual
Anglicized plural octopuses, it in fact originates as an
error. Octopus is not a simple Latin word of the second
declension, but a Latinized form of the Greek word oktopous, and
its 'correct' plural would logically be octopodes.
Other words ending in -us show a very varied pattern. ...
Tim McDaniel, quite fond of penes and clitorides
--
Tim McDaniel, tm...@panix.com; tm...@us.ibm.com is my work address
John Schilling
>On Thu, 24 Oct 2002, in rec.arts.sf.written,
>John Schilling <schi...@spock.usc.edu> said:
>>wth...@godzilla1.acpub.duke.edu writes:
>>>> I'm trying to get informed on the Runaway Greenhouse effect and that
>>>> Molten Lead Venus Scenario.
>>>> However, sterilizing earth by triggering a runaway greenhouse effect
>>>> seems to inevitably be a long term project. Probably mankind would be
>>>> extinct long before the point of no return is reached. But then who'd
>>>> keep the greenhouse gas generators running?
>>> The point is that once the planet reaches a certain
>>> threshold, though it is nowhere near as warm as Venus,
>>> the process will continue by itself, with no further
>>> help from us.
>>How does the carbon get out of the lithosphere? Because Earth
>>did not take the Venus route in the first place, we've had four
>>billion years for an alternate process to put most of our carbon
>>well out of reach of the atmosphere, and it is not obvious to me
>>that the process is reversable on anything less than a geologic
>>timescale.
>What carbon? The process William is talking about, the one which Venus
>underwent all those years ago, is a runaway *water* greenhouse effect.
>Carbon don't enter into it.
Carbon very definitely does enter into it. The bulk of the greenhouse
effect in the final stages may be water-based, but a great deal of carbon
dioxide is necessary to initiate the process. The ammount of carbon
dioxide Mr. Hyde (Dr. Hyde? That doesn't sound quite right in an SF
newsgroup...) suggested as necessary to set things in motion is not to
be found on Earth, save bound up in rocks.
Del Cotter
John Schilling <schi...@spock.usc.edu> said:
>Del Cotter <d...@branta.demon.co.uk> writes:
>>John Schilling <schi...@spock.usc.edu> said:
>>>wth...@godzilla1.acpub.duke.edu writes:
>>>> The point is that once the planet reaches a certain
>>>> threshold, though it is nowhere near as warm as Venus,
>>>> the process will continue by itself, with no further
>>>> help from us.
>>>
>>>How does the carbon get out of the lithosphere? Because Earth
>>>did not take the Venus route in the first place, we've had four
>>>billion years for an alternate process to put most of our carbon
>>>well out of reach of the atmosphere, and it is not obvious to me
>>>that the process is reversable on anything less than a geologic
>>>timescale.
>
>>What carbon? The process William is talking about, the one which Venus
>>underwent all those years ago, is a runaway *water* greenhouse effect.
>>Carbon don't enter into it.
>
>Carbon very definitely does enter into it. The bulk of the greenhouse
>effect in the final stages may be water-based, but a great deal of carbon
>dioxide is necessary to initiate the process. The ammount of carbon
>dioxide Mr. Hyde (Dr. Hyde? That doesn't sound quite right in an SF
>newsgroup...) suggested as necessary to set things in motion is not to
>be found on Earth, save bound up in rocks.
What you're doing is taking the entirely fallacious position that we
would have to liberate as much carbon as already exists in the Venerian
atmosphere, to effect a runaway greenhouse on Earth. If that were true,
your reasoning would be valid, since much of Earth's carbon is indeed
sequestered deep enough to make recovering it on historical timescales a
hopeless task.
But as William said, we could kick-start a water vapour greenhouse with
only 100 times the amount of CO2 as there currently is in the Earth's
atmosphere. That's only 4 x 10^16 kg of carbon, as opposed to the 10^20
kg in Venus's atmosphere. That's three and a half orders of magnitude
less.
Project Plowshare [1] explored the use of nuclear explosives to liberate
natural gas, and found by accident that the explosions also created
carbon dioxide from dolomite, to the tune of about 10^9 kg per megaton.
At that rate, you could do it with a few hundred thousand 100Mt bombs.
But why not use the natural gas itself? Methane is a much more
efficient greenhouse gas than CO2. CFCs are even better, 10,000 times
better weight for weight, you'd hardly have to mine any rocks at all to
make the required material. Fogg has considered the relative merits of
methane, CFCs, and explosives-derived CO2 in terraforming Mars [2]
It isn't true that you have to have a "great deal" of carbon dioxide to
initiate the process, certainly not more than a minuscule fraction of
all the carbon there is in the Earth, or even on the surface. You're
just wrong about having to drag it all out of the lithosphere.
--
. . . . Del Cotter d...@branta.demon.co.uk . . . .
[1] R. W. Taylor, E. L. Lee and J. H. Hill, "Interpreting the Chemical
Results of the Gasbuggy Experiment" Syposium on Engineering with Nuclear
Explosives CONF-700101, vol. 1, American Nuclear Society (1970)
[2] Martyn J. Fogg "A Synergic Approach to Terraforming Mars" Journal of
the British Interplanetary Society, vol. 45, pp.315-329 (1992)
Mark Reichert
> But why not use the natural gas itself? Methane is a much more
> efficient greenhouse gas than CO2. CFCs are even better, 10,000 times
> better weight for weight, you'd hardly have to mine any rocks at all to
> make the required material. Fogg has considered the relative merits of
> methane, CFCs, and explosives-derived CO2 in terraforming Mars [2]
Yes, but don't CFCs have that rather unfortunate side effect?
Or is it that a steadily thickening atmosphere will make up for the
removal of the ozone layer?
Andrew Maizels
> Yes, but don't CFCs have that rather unfortunate side effect?
>
> Or is it that a steadily thickening atmosphere will make up for the
> removal of the ozone layer?
Are you thinking about terraforming Mars or destroying all life on Earth?
Mars doesn't have an ozone layer, so that's not really something to
worry about. Unless you were planning to create one artificially (which
would be quite a job). In that case, you'd be better off using PFCs
(perfluorcarbons) instead.
On the other hand, if you want to destroy all life on Earth, getting rid
of the ozone layer seems to be a plus.
Andrew.
--
Google fthagn! Google fthagn! Ia Google! Ia! Ia!
wth...@godzilla6.acpub.duke.edu
> On Thu, 24 Oct 2002, in rec.arts.sf.written,
> John Schilling <schi...@spock.usc.edu> said:
>
> >wth...@godzilla1.acpub.duke.edu writes:
> >>> I'm trying to get informed on the Runaway Greenhouse effect and that
> >>> Molten Lead Venus Scenario.
>
> >>> However, sterilizing earth by triggering a runaway greenhouse effect
> >>> seems to inevitably be a long term project. Probably mankind would be
> >>> extinct long before the point of no return is reached. But then who'd
> >>> keep the greenhouse gas generators running?
> >
> >> The point is that once the planet reaches a certain
> >> threshold, though it is nowhere near as warm as Venus,
> >> the process will continue by itself, with no further
> >> help from us.
> >
> >How does the carbon get out of the lithosphere? Because Earth
> >did not take the Venus route in the first place, we've had four
> >billion years for an alternate process to put most of our carbon
> >well out of reach of the atmosphere, and it is not obvious to me
> >that the process is reversable on anything less than a geologic
> >timescale.
>
> What carbon? The process William is talking about, the one which Venus
> underwent all those years ago, is a runaway *water* greenhouse effect.
> Carbon don't enter into it.
Well, as Mr Schilling pointed out, the amount of carbon
I specified as being necessary to start a runaway
greenhouse effect is harder to extract than I had
thought. By about an order of magnitude.
True, I set the bar rather high at 100X (I suspect 20X would
be more than enough - we've had nearly that much (or perhaps
even more) in the past, but solar output was lower than).
But even 20X is a lot of carbon. If the numbers I posted
are correct (and they are old estimates), we'd have to
burn all known fossil fuels plus a fair amount of oil
shale to get 20X into the atmosphere.
It only later occurred to me that we could start a
runaway greenhouse effect much more easily with
CFCs or other molecules which are much, much, more
effective greenhouse gases than CO2. Or, even easier,
we could combine the two approaches. And we could
probably design absorbers which are even better than
CFCs.
I'm sure we could fry the planet if we wanted to, kicking
off a runaway greenhouse. Certainly within a couple of
centuries, probably within one.
Del Cotter
Mark Reichert <Mark_R...@hotmail.com> said:
>Del Cotter <d...@branta.demon.co.uk> wrote
>> But why not use the natural gas itself? Methane is a much more
>> efficient greenhouse gas than CO2. CFCs are even better, 10,000 times
>> better weight for weight, you'd hardly have to mine any rocks at all to
>> make the required material. Fogg has considered the relative merits of
>> methane, CFCs, and explosives-derived CO2 in terraforming Mars [2]
>
>Yes, but don't CFCs have that rather unfortunate side effect?
>
>Or is it that a steadily thickening atmosphere will make up for the
>removal of the ozone layer?
Oh goodness me, we mustn't damage the ozone layer while we're busy
destroying all life on Earth! :-)
Yes, as it happens, Fogg came down against using CFCs to terraform Mars
for that reason.
--
. . . . Del Cotter d...@branta.demon.co.uk . . . .
wth...@godzilla6.acpub.duke.edu
> In article <yv7zhefa...@godzilla6.acpub.duke.edu>,
> <wth...@godzilla6.acpub.duke.edu> wrote:
>
> > Well, we are not really trying, are we? I'd say if we
> > dedicated ourselves to the project we could do far
> > better. If we actually intended to produce a runaway
> > greenhouse, with little need to make economic sense,
> > I think we could mine much, much more. And it would help
> > to eliminate some of those nasty carbon sinks.
> >
> > The oceans hold about sixty times as much CO2 as the
> > atmosphere. Warmer oceans can hold less CO2, so there's
> > another feedback.
> >
> Are you sure that the project could be kept going as conditions
> worsen?
We'd have to design it with the assumption that
90-99% of the population would be dead long before
the finish. But I think we could do that. The whole
scenario does assume a massive death wish, after all.
And I did forget about the possibility of using
nuclear weapons to release CO2. I'm not sure how
efficient that is, though Fogg sent me a copy of
his "terraforming mars" paper long ago. I even
did a few model simulations based on it, though
the results were inconclusive (I had the wrong
model for the problem, basically).
Bill Snyder
> But I have faith in the Human Race. We can sterilize
> this planet!
I see that my ISP's server still carries alt.destroy.the.earth. And
it's still getting the occasional on-topic message.
--
Bill Snyder [This space unintentionally left blank.]
John Schilling
>schi...@spock.usc.edu (John Schilling) writes:
> Heck, without even trying we've managed to add enough
> CFCs to the atmosphere to make a real difference to
> climate. Come to think of it, the smart thing to do
> would be to ignore CO2 entirely and produce CFCs. Far
> more absorbing in the IR, and not absorbed by that
> pesky biosphere.
But correspondingly harder to make - can't just throw shale or
limestone in a furnace. And fluorine isn't terribly common,
may not be available in the quantities we need.
Fluorocarbons seem to be ~10,000 times more effective than CO2
as greenhouse gasses, so we need about ten billion tons of them.
Call that five billion tons of fluorine. Known recoverable reserves
are only 350 million tons; presumably we can find more but possibly
not enough or not cheaply enough.
>> For a hundred time current atmospheric CO2, you need six hundred
>> trillion tons of limestone or a quadrillion tons of oil shale.
>> I'm not sure there is that much oil shale to be had.
> Here and later I'm going to assume you are right in
> all your calculations.
> As of 1970 the fossil fuel inventory was about eleven
> times the atmospheric CO2. Shales were about eleven
> thousand times. Oil shales are of course only a tiny
> fraction of that.
Right, but only the oil shales seem worth bothering with. Limestone
works, we've got plenty of it, and we can easily extract the carbon
content. It's the scale of the effort that is problematic; whether
limestone or shale, there's a *lot* of rock to be dug up and put in
the furnace.
> Limestone,
>> yes, but all the world's mining industries combined are only good
>> for bringing up fifty billion tons of ore per year, so you're
>> talking twelve thousand years of dedicated effort.
> Well, we are not really trying, are we? I'd say if we
> dedicated ourselves to the project we could do far
> better. If we actually intended to produce a runaway
> greenhouse, with little need to make economic sense,
> I think we could mine much, much more.
I assumed we could do about an order of magnitude better, on account
of mining, processing, energy production and the associated support
industries making up ~10% of the global economy as is.
> The oceans hold about sixty times as much CO2 as the
> atmosphere. Warmer oceans can hold less CO2, so there's
> another feedback.
Most of that CO2 is in the deep ocean, which is not even close to
saturation. So I don't think that feedback helps in triggering the
runaway greenhouse effect, it just accelerates the process once we
cross the threshold.
I had considered pumping deep ocean water to the surface to get at
its CO2; this turns out to require a factor of two more energy than
breaking down limestone, so it doesn't look like the way to go. But
not out of the question.
>> Oh, and three hundred quadrillion kilowatt-hours of electricity to break
>> down the limestone. That's twenty thousand years of total generation
>> from all sources, not just nuclear.
> Now we're talking. You've more or less convinced me
> we couldn't do it in a hundred years, by CO2, but I'd still
> bet on a thousand.
Yeah. It would take some clever planning, we'd have to front-load
the labor budget in particular, but it might be doable.
>> But it takes more than "a few thousand workers for a couple decades".
>> It takes all six billion of us for the whole time, all working the
>> limestone mines and CO2 "refineries" and nuclear powerplants to run
>> them, even at current levels of automation.
>>
>> Which means that the process fails when the atmosphere gets toxic,
>> heck, when the climate gets nasty enough to shut down most agriculture.
>> We reach an equilibrium when things are sufficiently bad that the
>> surviving population is fully employed in keeping itself alive and
>> has no time for the Great Planetary Suicide Project.
> Most of the population is gone well before the project
> ends. A couple of hundred million are left running
> the machinery built in phase 1.
Couple hundred million, that might work.
> I think some people begin to die when the atmosphere
> reaches 8X.
And a lot of the rest won't be terribly "productive" as far as this
project is concerned, being fully occupied just in staying alive.
The trick is to do as much of the work as possible before dumping
the CO2 into the atmosphere. Mine and crush all the limestone or
shale needed for the project before reducing any of it. In parallel,
build a hundred or so Venusiforming plants, each centered around a
hundred or so large nuclear powerplants and electric furnaces.
Warehouses with centuries' worth of spare parts for all the machinery
involved, plus fuel elements for the reactors. An underground or
otherwise sealed and isolated city for the technicians and their
families (we need many generations of technicians). Stockpiles of
food, etc, etc.
And for each of the hundred Venusiforming plants, an Everst-sized
mountain of crushed limestone right at hand.
Accumulating all this, especially those artificial mountains, is going
to take most of your thousand years of global effort. Then we kill off
most of the population and turn on the furnaces. No, scratch that - with
due reverence for this project's historical antecedents, we just march
the bulk of Earth's population into the furnaces and turn them on. There's
carbon in them there corpses. The remaining millions spend the remaining
centuries dumping truckloads of rock into the furnaces, maintaining the
machinery, and breeding new generations of technicians until completion.
Somewhere along the line, the oceans boil and everyone dies. But by that
point, the process no longer requires human assistance.
>> We can certainly arrange a catastrophic climate change if we work at
>> it, and maybe if we don't. But universally lethal climate change, I
>> don't see that as possible with any human effort in the near future.
>> No Venusian infernos, sorry.
> It's difficult - and more difficult than I thought, I
> admit - but with CFCs (or some other molecule we design
> for the project) I think we can do it fairly rapidly.
> You've convinced me that to do it with CO2 will take
> longer than I thought.
> But I have faith in the Human Race. We can sterilize
> this planet!
OK, given a thousand years or so of dedicated effort, yes.
Jordan179
> >schi...@spock.usc.edu (John Schilling) wrote in message news:<ap9cpc$537$1...@spock.usc.edu>...
> >>
> >> Nuclear *war* is a non-starter for causing the extinction of, well,
> >> anything. War is by definition a conflict, with each party's efforts
>
> You might get extinction of some close-to-the edge species.
Oh, I'm pretty sure that you _would_ get mass extinctions following
anything but a very limited nuclear war. Yet another reason why we
really need planetary unification.
> Unfortunately, I can't exclude that possibility. I don't think the
> human race has had its last murderously bad but very attractive idea.
>
> About 20% of Cambodians were killed for no particular reason by their
> own government. I wouldn't be surprised to see some country wipe out
> 80% or 90% of its population one of these years. (I'm not sure whether
> this belief is a matter of habitual pessimism, or a feeling that as
> the world gets richer, it's easier to indulge in bad ideas and the
> tools for carrying them out get cheaper.)
Sadly, I agree with you. Yet another reason why we really need to
start serious space colonization.
> More bleak: Making the world uninhabitable would presumably be a high
> tech project, but it's interesting that modern genocides except
> for the holocaust have been fairly low tech.
Yes.
And a lot of species are getting wiped out, right now, in Africa and
South America, through fairly low-tech means.
Sincerely Yours,
Jordan
Mark Reichert
> Are you thinking about terraforming Mars or destroying all life on Earth?
Sorry, I misunderstood what was being attempted. Something made me
think that this was to warm up the Earth when the next Ice Age hits.
Paul Austin
<wth...@godzilla6.acpub.duke.edu> wrote ...
> True, I set the bar rather high at 100X (I suspect 20X
would
> be more than enough - we've had nearly that much (or perhaps
> even more) in the past, but solar output was lower than).
> But even 20X is a lot of carbon. If the numbers I posted
> are correct (and they are old estimates), we'd have to
> burn all known fossil fuels plus a fair amount of oil
> shale to get 20X into the atmosphere.
William, you keep saying that CO^2 levels were higher "then" but the
solar "constant" was also lower.
When was "then"? The Sun is in the flat part of its evolution and its
irradiance is changing very slowly, until it leaves the Main Sequence.
I think (but don't know) that it hasn't changed much in a secular
trend since the Cambrian. Do you know if that's the case?
--
Conscience, that quiet voice that says "Someone may be watching"
Paul F Austin
pfau...@bellsouth.net
wth...@godzilla6.acpub.duke.edu
> William, you keep saying that CO^2 levels were higher "then" but the
> solar "constant" was also lower.
>
> When was "then"? The Sun is in the flat part of its evolution and its
> irradiance is changing very slowly,
If I remember my one and only astronomy course, most stars
evolve slowly and vertically away from the main sequence
for a time, not covering much ground in the HR diagram,
true, but getting hotter as core temperatures slowly
rise and the fusion rate increases. That's the effect
I've been talking about. For the sun this results in
an increase in the solar constant of 1% per hundred
million years. Other things being equal, climate models
would predict a 1-1.5 degree warming as a result.
The last time CO2 was semi-plausibly as high as 20X
was in the Ordovician, about 400 million years ago,
so the solar constant was 4% smaller, resulting in
about 14 watts/square meter less average solar radiation
at the top of the atmosphere than today. Not enough to
eliminate the effect of 20X CO2, but enough to make a
fair dent in it.
I think the latest estimates for Ordovician CO2 are coming
in at well under 20X, but this certainly isn't a
solved problem.
until it leaves the Main Sequence.
> I think (but don't know) that it hasn't changed much in a secular
> trend since the Cambrian. Do you know if that's the case?
Well, it would be 5% since the Cambrian, using the
above rule of thumb. As I understand it, the
principal uncertainty lies in the initial H/He
ratio for the sun. For different estimates the
early core temperature of the sun is different, hence
the rate of production of He changes, and so the rate of
growth is slightly different. Our estimates for 300 Ma,
for example, ranged from 2.7 to 3.3%.
Paul Austin
<wth...@godzilla6.acpub.duke.edu> wrote ...
> "Paul Austin" <pfau...@bellsouth.net> writes:
>
>
> > William, you keep saying that CO^2 levels were higher "then" but
the
> > solar "constant" was also lower.
> >
> > When was "then"? The Sun is in the flat part of its evolution and
its
> > irradiance is changing very slowly,
>
> If I remember my one and only astronomy course, most stars
> evolve slowly and vertically away from the main sequence
> for a time, not covering much ground in the HR diagram,
> true, but getting hotter as core temperatures slowly
> rise and the fusion rate increases. That's the effect
> I've been talking about. For the sun this results in
> an increase in the solar constant of 1% per hundred
> million years. Other things being equal, climate models
> would predict a 1-1.5 degree warming as a result.
Thanks.
A nit. A star doesn't leave the Main Sequence until helium burning
commences. I suspect the increased luminosity during Main Sequence
burning comes from the increased surface area of hydrogen burning as
the star ages. But then _my_ few courses in astronomy were thirty
years in the past.
--
"A fanatic is one who can't change his mind
and won't change the subject"
-------------------------------------
Paul F Austin
pfau...@bellsouth.net
wth...@godzilla6.acpub.duke.edu
> <wth...@godzilla6.acpub.duke.edu> wrote ...
> > "Paul Austin" <pfau...@bellsouth.net> writes:
> >
> >
> > > William, you keep saying that CO^2 levels were higher "then" but
> the
> > > solar "constant" was also lower.
> > >
> > > When was "then"? The Sun is in the flat part of its evolution and
> its
> > > irradiance is changing very slowly,
> >
> > If I remember my one and only astronomy course, most stars
> > evolve slowly and vertically away from the main sequence
> > for a time, not covering much ground in the HR diagram,
> > true, but getting hotter as core temperatures slowly
> > rise and the fusion rate increases. That's the effect
> > I've been talking about. For the sun this results in
> > an increase in the solar constant of 1% per hundred
> > million years. Other things being equal, climate models
> > would predict a 1-1.5 degree warming as a result.
>
> Thanks.
>
> A nit. A star doesn't leave the Main Sequence until helium burning
> commences.
Yes. It is still an MS star, but if you plot its position
on the HR diagram every so often you can see an upwards
trajectory. But as you say, when it starts to burn He
it leaves the MS entirely.
I suspect the increased luminosity during Main Sequence
> burning comes from the increased surface area of hydrogen burning as
> the star ages.
That sounds sensible. But I've been told that a
higher proportion of He causes a warmer core
(more dense, higher pressure) which makes fusion
more efficient even though it is still far too
cold for He Fusion.
But then _my_ few courses in astronomy were thirty
> years in the past.
More or less the same here, 1973-74.
Andrea Leistra
<wth...@godzilla6.acpub.duke.edu> wrote:
>"Paul Austin" <pfau...@bellsouth.net> writes:
>> A nit. A star doesn't leave the Main Sequence until helium burning
>> commences.
>
> Yes. It is still an MS star, but if you plot its position
> on the HR diagram every so often you can see an upwards
> trajectory. But as you say, when it starts to burn He
> it leaves the MS entirely.
Not quite.
A star leaves the main sequence once hydrogen is exhausted in the
core; it then evolves more-or-less horizontally on the HR diagram
(to lower temperatures at an essentially constant luminosity)
as the envelope expands, then as a red giant it evolves to higher
luminosity at a nearly-constant temperature. During the red giant
phase it is not burning helium, but rather burning hydrogen in
a thin "shell"; once helium fusion begins the effective temperature
increases again.
It's important to realize that the core temperature and the
effective temperature, for the same star at given stages of
evolution, are not necessarily correlated. The core of a
red giant of 1 solar mass is hotter than that of the same
star on the main sequence, even though the surface temperature
is lower. There's a lot of energy that goes into expanding the
atmosphere, rather than coming out as radiation.
--
Andrea Leistra