Nuclear War

The idea of nuclear war and a massive global distruction has been on my mind recently (and apparently the minds of other dopers as well.) The threat of complete extinction of all species on earth has been brought up in numerous threads, Nuclear Winter and Nuclear Carpet Bombing and such…

My question is:

What would happen if both the USA and Russia deployed all of their Nuclear weapons? Would the atmosphere change into Nuclear fallout all over the world? What are the odds that life would survive? Is the worry about Nuclear war exaggerated? Surely hundreds of millions would die from the explosions and corresponding radiation, but would all life cease to exist? Would the world end?

That’s a pretty big question.

Would a full scale nuclear exchange sterilise the Earth? Not likely. Life is very, very versatile, and it’s been through rough times before. (And as Stephen Jay Gould said, this is not the Age of Humans, nor was there ever an Age of the Dinosaurs. it is and was the Age of Bacteria. Bacteria have always ruled the Earth, numbers and diversity-wise. Nuclear war isn’t likey to kill all of them, everywhere.)

Nobody knows for sure what exactly would happen. Before Carl Sagan et. al. developed the theory of a post-holocaust nuclear winter, most scientists probably assumed that even though there would obviously be tremendous death and destruction and fallout, the Earth’s biosphere would likely come through largely unscathed (apart from the ensuing giant mutant cockroaches :wink: ). That is, because most of the weapons were targeted on relatively small patches of the Earth’s surface, those patches would be greatly affected but most of the planet (the oceans, most of the land masses of the southern hemisphere) would come off largely unscathed (apart from radioactive fallout which, as Chernobyl showed us, has an effect, but it doesn’t immediately kill everything it touches).

Nuclear winter is the theory that a full-scale nuclear exchange would throw so much ash and dust into the upper atmosphere that it would blot out the Sun, greatly disrupting Earth’s climate. That’s not to say that day would be turned to night, but on a global scale the amount of the Sun’s energy reaching the Earth’s surface would be substantially reduced. This would disrupt many processes, including large-scale ocean currents (critically important to global climate - remember El Nino?), the growth of plankton and krill (the anchor of the oceanic food chain) and the growth of terrestrial plants (grassland would turn to desert, rainforest to savannah, that kind of thing). A new ice age could be triggered. Or not.

The upshot of the nuclear winter theory is that it predicts a massive extinction of species and rearrangement of the environment. Would the planet be sterilised? Not likely. But it would be very different.

By the way, I don’t want to come of as Mr Know-It-All. I’m no expert. The above is just what I’ve gathered from reading Discover Magazine and Scientific American for the past twenty years.

Don’t worry about it Kamandi, all information is useful. I just have a hard time believing that all life would be extinguished- even all human life. I mean, what about islands or remote parts of the world? Even remote parts of the country- like Kansas. I just can’t image that level of destruction.

Don’t forget about the cobalt bomb, as mentioned in Dr. Strangelove. If such a doomsday device was ever constructed and used, most if not all higher life forms would be killed. That’s not saying that life would end, but it would be millions of years before the surviving bacteria/cockroaches/etc. evolved to fill the empty ecological niches. From Encyclopedia.com

All life wouldn’t be extinguished; there’s always the cockroaches. :wink:

Of course, the obliteration of all human life would be a major bummer to most of the folks on this board, who have a biased interest at stake.

Is a cobalt bomb possible? I mean, if it can be made, then surely some wacked out fanatical group should be scrambling to get the resources together.

For the Cobalt Bomb theory, what about fallout shelters? Granted they were before my time, but couldn’t you store 5-6 years worth of food in there and just wait it out?

IIRC, the assumptions used for the ‘nuclear winter’ scenario were significantly tilted towards the ‘worst case’. Things like very large weapons, ground bursts, and the like were factored in. In all likelihood, we’d have something like 1919 (the year without a summer), but not significantly worse, climate-wise. What would be more serious would be economic impact. Expect the largest and longest recession ever. Countires that depend on the US, Europe, or Russia for foodstuffs would be in real trouble. Wide-spread famine is probable. Actual technological decline would be minimal (many quite advance nations are on no-one’s target list), as would actual knowledge loss, but the distribution of the ‘haves’ and ‘have-nots’ would be radically changed.

The nations directly involved in the war would become third-world nations, and would likely balkanize.

Those are my semi-informed guesses, anyway…

Now, for a non-guess: On the subject of cobalt weapons and the like, check this thread and this one. Cobalt bombs don’t scare me much.

Does that mean the world would be populated with Lawyers and Used Car Salesmen?

Tranquilis,

I just finished reading your posts on Cobalt bombs, great stuff. What do you do by the way? Is it even imaginable that a nation could get together enough Cobalt (or make it, I’m not familar with the stuff) to ever even reach the CSCA 's minimums?

Aside from a meteor impact, is there a way for man to wipe out all life on earth? Say some way of creating a greenhouse effect similar to what Venus has going on.

Well, these days I solve problems for a pharmaceutical company, and before that, I was a consultant, but before that, I spent 15 years in the Nav, most of it either running nuclear reactors, or repairing them (and associated systems).

It would be tremendously difficult to create a large enough quantity of Co-60 to produce anything more than a few enhanced-fallout weapons. Even then, you’d need to be constantly replacing the material, as Co-60 has a relatively short half-life, at 5.27 years. I can’t see any nation bothering anyway, as you can get nearly the same effect by employing ground-bursts, at the cost of using a special weapon in a less-than-efficient manner.

As for other means of wiping-out human life, well, I can only think of a few, and short of meteorites, the best shot is biological warfare. You’d need a lot of your chosen agents, and you’d probably need a number of different agents, so that if some number of people turn out immune to one, another would get them. You’d need to have an agent that was very persistant, highly infectious, and capable of long-term survival outside the human body. You’d have to seed the stratosphere with massive amounts of your agents to get global coverage, which means that whatever nasties you choose will need to be UV resistant, too. Pretty tough mission requirements, if you ask me.

Even if you could meet the mission parameters, I wouldn’t bet on 100% success. Humanity exists on this planet in very isolated places, and is remarkably tough.

The next best choice would be to pollute ourselves to death. It’ll take longer, but can be done more thoroughly.

Gah, enough grimness for one day.

Just a side point to liquid. would have been toast in the event of a U.S/USSR war. There’s a lot of missile silos out there which would be a primary target for a soviet attack. Kansas as well as most of the midwest

that should say Kansas would be toast. As well as irradiating the primary growing region for the U.S

This is kind of a worst-case scenario, but I’ve heard that plankton and krill are at the bottom of the food web for the whole planet’s ecosystem. And if they were wiped out (by a nuclear winter), that the rest of the food chain would fall like dominoes within a couple months. Sorry, I don’t have a cite and I don’t know if other biologists would agree.

I used to think that Nuclear Winter was pretty much a given, but now I’m more skeptical. It seems like it would be very difficult to calculate the amount of dust generated, how high it would travel, and how long it would stay up. Does anyone know how widely accepted this scenario is?

I’m also curious about radiation. I know that nukes now are cleaner than the ones used on Hiroshima and Nagasaki, unless they are designed with the goal of spreading radioactivity. Does anyone have an idea of how much radiation would be realeased and whether it would spread worldwide?

But could a Nuclear Winter ever happen?

I don’t know but I think so. IIRC a slight global temperature drop was recorded after Mt. St. Helens blew her top. I guess one would need to know how much dust was left airborn for a year from that compared to how much dust one could expect to get from a lot of nukes going off.

Maybe we don’t have enough nukes to achieve a full blown nuclear winter but the theory seems sound if you manage to get enough dust up in the atmosphere. Even if you don’t get a full-blown winter certainly the temperature could decrease to some extent and the effects of that might still be traumatic.