How many nukes does Russia have, really?

[Lexicus]

It's also the destruction (combustion) of large amounts of material in cities IIRC.

 

[uppi]

I'd love to see the assumptions behind this, because honestly, it seems incredibly far fetched.

The total yield of all nuclear devices detonated by mankind is approx. 540 megatons. This includes surface, airburst, underground and underwater tests with yields far exceeding the warheads in this scenario, and the ecological impact was nowhere near this. The 1883 Krakatoa eruption was estimated to be around 200 megaton in yield, and while it produced global environmental effects, they were nowhere near this-in fact, another Krakatoa would just about counteract global warming for the next decade or so.

The full paper is there for me, and it says open access so I guess you should be able to see it? Of course they are very technical, and I know nothing about this, but I think most of the cooling is caused by the release of Black Carbon (BC), which I guess would be released by nuclear weapons going off near ground with carbon based life forms on it. This is was usually avoided in nuclear testing.

They cite this paper for the estimate of the black carbon emissions. Section 6 details the underlying assumptions. Basically, they assume that city centers are hit and the explosion creates a secondary firestorm which then creates all this soot. Not so much from carbon based lifeforms but rather from carbon based material (wood, oil, plastics, ...). There is a lot of guessing involved, so the numbers could be quite off.

Using this model, it obviously matters what it hit with the nuclear explosion. A remote mountain range is going to have very different effects than a city center. So the 200 atmospheric tests made in the 1950ies did not have such a catastrophic effect.

 

[Ajidica]

I had a quick look, and I found this:

We present the first study of the global impacts of a regional nuclear war with an Earth system model including atmospheric chemistry, ocean dynamics, and interactive sea ice and land components. A limited, regional nuclear war between India and Pakistan in which each side detonates 50 15 kt weapons could produce about 5 Tg of black carbon (BC). This would self-loft to the stratosphere, where it would spread globally, producing a sudden drop in surface temperatures and intense heating of the stratosphere. Using the Community Earth System Model with the Whole Atmosphere Community Climate Model, we calculate an e-folding time of 8.7 years for stratospheric BC compared to 4–6.5 years for previous studies. Our calculations show that global ozone losses of 20%–50% over populated areas, levels unprecedented in human history, would accompany the coldest average surface temperatures in the last 1000 years. We calculate summer enhancements in UV indices of 30%–80% over midlatitudes, suggesting widespread damage to human health, agriculture, and terrestrial and aquatic ecosystems. Killing frosts would reduce growing seasons by 10–40 days per year for 5 years. Surface temperatures would be reduced for more than 25 years due to thermal inertia and albedo effects in the ocean and expanded sea ice. The combined cooling and enhanced UV would put significant pressures on global food supplies and could trigger a global nuclear famine. Knowledge of the impacts of 100 small nuclear weapons should motivate the elimination of more than 17,000 nuclear weapons that exist today.​

Change in frost-free growing season in days for (a) January to December in the Northern Hemisphere and (b) July to June in the Southern Hemisphere. Values are 5 year seasonal ensemble averages for years 2–6, experiment minus control.

If that is one and a half megatonnes, then it will not take many of Russia's 6000 to end civilisation.

I've seen a number of different projections on the environmental impact of nuclear warfare, and they are all heavily reliant on assumptions. One has to make a lot of assumptions about ratio of airburst to groundburst, how much dirt is kicked up, etc, and then feed it all into a climate model which are extremely complex.
I prefer to focus on the more immediate effects. Suppose America and France get into a nuclear war, and the US Navy manages to sink all but one French ballistic missile submarine. That's 16 missiles launched at America. Suppose US ballistic missile defense is able to eliminate half of those (which I understand to be a very optimistic view of ballistic missile defense systems). That's 8 missiles coming in with 6-10 200kt warheads. Let's assume 8 warheads each, so 64 warheads, total tonnage 12,800kt or about 13 megatons.* British government White Papers in the Cold War suggested it took about 2 megaton to flatten a city the size of London. That gives us about 6 major cities totally destroyed. If the warheads were targeted at the US east coast, there goes New York, surroundings of New York, Washington DC, surroundings of DC, Atlanta, and some warheads for targeted strikes. That's a couple tens of millions dead right there, to say nothing of those who will die from blast damage and collapse of civil society. And that is all working under a 'best case scenario'. Just about every nuclear capable country in the Cold War realized this, and is why all of them understood you cannot win a nuclear war.

*French nuclear subs and weapons are smaller compared to American. For comparison, a single Ohio-class has 24 missiles, 8 warheads/missile, and each warhead is around 500kt (or 200kt depending on which warhead is used, wiki suggests both are in use). Russian Borei-class have 16 missiles, 8 warheads/missile, at about 150kt a warhead.

 

[Kaitzilla]

A video was made over the summer to shine some more light on a modern nuclear war.

Russia sure has a lot of boom in Kaliningrad!

Ugh, everyone died.

Another video came out hypothesizing World War 3 if POTUS picked attack option #2, Russian cities.

What struck me was the raging fires afterwards.
It reminded me of the Canadian wild fire cloud that hit New York City that one day a few weeks ago.

Things got bad in 3 hours, but imagine if the smoke was deadly radioactive and you had no choice but to breathe it in.

Nukes release unreal amounts of x-rays which causes everything to give off thermal heat waves a few seconds later.
Everything in all directions is on fire in about 5 seconds I think.