Nuclear Winter.

If nothing else this could wipe us out by itself, the following excerpts are from an article by Carl Sagan on Nuclear war.

Our baseline case, as in many other studies, was a 5000-megaton war with only a modest fraction of the yield (20 percent) expended on urban or industrial targets. Our job, for each case, was to follow the dust and smoke generated, see how much sunlight was absorbed and by how much the temperatures changed, figure out how the particles spread in longitude and latitude, and calculate how long before it all fell out in the air back onto the surface. Since the radioactivity would be attached to these same fine particles, our calculations also revealed the extent and timing of the subsequent radioactive fallout.

So far so scientific…he continues:

The results of our calculations astonished us. In the baseline case, the amount of sunlight at the ground was reduced to a few percent of normal-much darker, in daylight, than in a heavy overcast and too dark for plants to make a living from photosynthesis. At least in the Northern Hemisphere, where the great preponderance of strategic targets lies, an unbroken and deadly gloom would persist for weeks.

Hmmm not good…:

Even more unexpected were the temperatures calculated.

In the baseline case, land temperatures, except for narrow strips of coastline, dropped to minus 250 Celsius (minus 13 degrees Fahrenheit) and stayed below freezing for months — even for a summer war. (Because the atmospheric structure becomes much more stable as the upper atmosphere is heated and the low air is cooled, we may have severely underestimated how long the cold and the dark would last.) The oceans, a significant heat reservoir, would not freeze, however, and a major ice age would probably not be triggered. But because the temperatures would drop so catastrophically, virtually all crops and farm animals, at least in the Northern Hemisphere, would be destroyed, as would most varieties of uncultivated or domesticated food supplies. Most of the human survivors would starve.

Really not good. And he can’t even factor in a Supercomputer bent of terminating all humans.

It gets worse.

In addition, the amount of radioactive fallout is much more than expected. Many previous calculations simply ignored the intermediate time-scale fallout. That is, calculations were made for the prompt fallout — the plumes of radioactive debris blown downwind from each target-and for the long-term fallout, the fine radioactive particles lofted into the stratosphere that would descend about a year later, after most of the radioactivity had decayed. However, the radioactivity carried into the upper atmosphere (but not as high as the stratosphere) seems to have been largely forgotten. We found for the baseline case that roughly 30 percent of the land at northern midlatitudes could receive a radioactive dose greater than 250 rads, and that about 50 percent of northern midlatitudes could receive a dose greater than 100 rads. A 100-rad dose is the equivalent of about 1000 medical X-rays. A 400-rad dose will, more likely than not, kill you.

Well shoot…sounds like we’re toast.

The cold, the dark and the intense radioactivity, together lasting for months, represent a severe assault on our civilization and our species. Civil and sanitary services would be wiped out. Medical facilities, drugs, the most rudimentary means for relieving the vast human suffering, would be unavailable. Any but the most elaborate shelters would be useless, quite apart from the question of what good it might be to emerge a few months later. Synthetics burned in the destruction of the cities would produce a wide variety of toxic gases, including carbon monoxide, cyanides, dioxins and furans. After the dust and soot settled out, the solar ultraviolet flux would be much larger than its present value. Immunity to disease would decline. Epidemics and pandemics would be rampant, especially after the billion or so unburied bodies began to thaw. Moreover, the combined influence of these severe and simultaneous stresses on life are likely to produce even more adverse consequences — biologists call them synergisms — that we are not yet wise enough to foresee.

Wow…Simply wow.

So far, we have talked only of the Northern Hemisphere. But it now seems – unlike the case of a single nuclear weapons test — that in a real nuclear war, the heating of the vast quantities of atmospheric dust and soot in northern midlatitudes will transport these fine particles toward and across the Equator. We see just this happening in Martian dust storms. The Southern Hemisphere would experience effects that, while less severe than in the Northern Hemisphere, are nevertheless extremely ominous. The illusion with which some people in the Northern Hemisphere reassure themselves — catching an Air New Zealand flight in a time of serious international crisis, or the like — is now much less tenable, even on the narrow issue of personal survival for those with the price of a ticket.

So even going South might amount to a whole lot of nothing, Sorry John and Sarah.

Wait what about a 100 Megaton Nuclear war?

Glad you asked.

But what if nuclear wars can be contained, and much less than 5000 megatons is detonated? Perhaps the greatest surprise in our work was that even small nuclear wars can have devastating climatic effects. We considered a war in which a mere 100 megatons were exploded, less than one percent of the world arsenals, and only in low-yield airbursts over cities. This scenario, we found, would ignite thousands of fires, and the smoke from these fires alone would be enough to generate an epoch of cold and dark almost as severe as in the 5000 megaton case. The threshold for what Richard Turco has called The Nuclear Winter is very low.

Yeah Carl liked to cover his bases.

What does this say about Nuclear Winter is quite simple the odds of enough humanity surviving to even put up a fight against the machines is unlikely.

Let alone creating re-enforcements.

Original Article

It seems humans surviving a Nuclear Winter without scary robots is unlikely enough…perhaps that’s why the Terminator films are classified as science fiction.

Ross Out.