And the reduced sunlight increases the already snowballing ecological die-off from industrial/military pollution/destruction.

http://climate.envsci.rutgers.edu/pdf/RobockToonSciAmJan2010.pdf

Worry has focused on the U.S. versus Russia, but a regional nuclear war between India and Pakistan could blot out the sun, starving much of the human race

b y a l a n r o b o c k a n d o w e n b r i a n t o o n

Twenty-five years ago international teams of scientists showed that a nuclear war between the U.S. and the Soviet Union
could produce a “nuclear winter.” The smoke from vast fires started by bombs dropped on cities and industrial areas would envelop the planet and absorb so much sunlight that the earth’s surface would get cold, dark and dry, killing plants
worldwide and eliminating our food supply. Surface temperatures would reach winter values in the summer. International discussion about this prediction, fueled largely by astronomer Carl Sagan, forced the leaders of the two superpowers
to confront the possibility that their arms race endangered not just themselves but the entire human race. Countries large and small demanded disarmament.

Nuclear winter became an important factor in ending the nuclear arms race. Looking back later, in 2000, former Soviet Union leader Mikhail S. Gorbachev observed, “Models made by Russian and American scientists showed that a nuclear war would result in a nuclear winter that would be extremely destructive to all life on earth; the knowledge of that was a
great stimulus to us, to people of honor and morality, to act.”
Why discuss this topic now that the cold war has ended? Because as other nations continue to acquire nuclear weapons, smaller, regional nuclear wars could create a similar global catastrophe. ...

...Regional War Threatens the World
By deploying modern computers and modern climate models, the two of us and our colleagues have shown that not only were the ideas of the 1980s correct but the effects would last for at least 10 years, much longer than previously
thought. And by doing calculations that assess decades of time, only now possible with fast, current computers, and by including in our calculations the oceans and the entire atmosphere—also only now possible—we have found that the
smoke from even a regional war would be heated and lofted by the sun and remain suspended in the upper atmosphere for years, continuing to block sunlight and to cool the earth. ...

... volcanic particles remain airborne for about two years, but smoke from nuclear fires would last a decade.

Killing Frosts in Summer
The climatic response to the smoke was surprising. Sunlight was immediately reduced, cooling
the planet to temperatures lower than any experienced for the past 1,000 years. ...

... The models also showed a 10 percent reduction in precipitation worldwide. Precipitation, river flow and soil moisture all decreased because blocking sunlight reduces evaporation and weakens the hydrologic cycle. Drought was largely concentrated in the lower latitudes, however, because global cooling would retard the Hadley air circulation pattern in the tropics, which produces a large fraction of global precipitation. In critical areas such as the Asian monsoon regions,
rainfall dropped by as much as 40 percent. ...

... In addition to the cooling, drying and darkness, extensive ozone depletion would result as the smoke heated the stratosphere; reactions that create and destroy ozone are temperature-dependent. ... ... Ultra-violet radiation on the ground would increase significantly because of the diminished ozone. ...

How many years until oxygen production becomes too thin to maintain healthy function and becomes insufficient to support life, when at current rates of ecological die-off - snowballing far more quickly than was recognized - this stage occurs within decades unless industrial/military pollution/destruction is ended immediately?

And that's not considering the global effects of radiation, which I imagine those profiting from this sort of thing plan to miss while comfortably sipping champagne On The (frozen) Beach, being the deluded unscientific fat-heads they are.

And regarding sulfate particles proposed for 'geoengineering' to maintain profitable, if toxic and sickening, industrial/fossil fuel air pollution levels rather than moving to greener tech:

... Eruptions.
Explosive volcanic eruptions, such as those of Tambora in 1815, Krakatau in 1883 and Pinatubo in 1991 provide several lessons.
The resulting sulfate aerosol clouds that formed in the stratosphere were transported around the
world by winds. The surface temperature plummeted after each eruption in proportion to the thickness of the particulate cloud. After the Pinatubo eruption, the global average surface temperature dropped by about 0.25 degree C. Global precipitation, river flow and soil moisture all decreased. Our models reproduce these effects. ...

Welcome, more drought!

(Not that we know what sulfates might be sprayed - probably whatever from toxic industrial wastes, as have been used for fluoridation of water, I'd think. Saves on toxic waste sites.)

This predates the studies we used to be able to access on the internet, cell studies and others, but I could at least find this and it's getting too close to 4 AM...

https://www.ncbi.nlm.nih.gov/pubmed/3780648

Format: Abstract

Send to
Environ Res. 1986 Dec;41(2):514-28.
Comparative study of various methods used for determining health effects of inhaled sulfates.
Drummond JG, Aranyi C, Schiff LJ, Fenters JD, Graham JA.
Abstract

Various health effect parameters were compared to determine which tests were the most sensitive indicators of toxic effects of exposure to metallic sulfate aerosols. Inhalation studies were conducted involving either single 3-hr exposure to various concentrations of cupric sulfate (0.43-2.64 mg/m3 SO4), aluminum sulfate (1.65-2.75 mg/m3 SO4), and aluminum ammonium sulfate (1.47-3.81 mg/m3 SO4) or multiple (five and ten) daily 3-hr exposures to cupric sulfate (0.1 mg/m3 SO4). The test parameters studied in male and female CD1 mice were changes in mortality after respiratory infection with Group C Streptococcus zooepidemicus; pulmonary bactericidal activity; pulmonary cell number, type, viability, and ATP content; and pulmonary morphology by scanning electron microscopy. Tracheal ciliary beating frequency and morphology were also studied in both CD1 mice and Syrian golden hamsters. Differences in bacteria-induced mortality rate appeared to be the most sensitive and consistent indicators of pollutant damage. The other parameters produced evidence of damage but generally only at the higher pollutant concentrations. Cupric sulfate was the most toxic of the three sulfates, but the differences between the toxicity of the aluminum sulfate and aluminum ammonium sulfate were less clear.Format: Abstract

Environ Res. 1986 Dec;41(2):514-28.
Comparative study of various methods used for determining health effects of inhaled sulfates.
Drummond JG, Aranyi C, Schiff LJ, Fenters JD, Graham JA.
Abstract

Various health effect parameters were compared to determine which tests were the most sensitive indicators of toxic effects of exposure to metallic sulfate aerosols. Inhalation studies were conducted involving either single 3-hr exposure to various concentrations of cupric sulfate (0.43-2.64 mg/m3 SO4), aluminum sulfate (1.65-2.75 mg/m3 SO4), and aluminum ammonium sulfate (1.47-3.81 mg/m3 SO4) or multiple (five and ten) daily 3-hr exposures to cupric sulfate (0.1 mg/m3 SO4). The test parameters studied in male and female CD1 mice were changes in mortality after respiratory infection with Group C Streptococcus zooepidemicus; pulmonary bactericidal activity; pulmonary cell number, type, viability, and ATP content; and pulmonary morphology by scanning electron microscopy. Tracheal ciliary beating frequency and morphology were also studied in both CD1 mice and Syrian golden hamsters. Differences in bacteria-induced mortality rate appeared to be the most sensitive and consistent indicators of pollutant damage. The other parameters produced evidence of damage but generally only at the higher pollutant concentrations. Cupric sulfate was the most toxic of the three sulfates, but the differences between the toxicity of the aluminum sulfate and aluminum ammonium sulfate were less clear.

Even just regarding the 'geoengineering', with reduced sunlight and moisture, and a steady supply of whatever's profitably spewed into the stratosphere at public cost (but with 'the public' competing with slave labour in Malaysia for wages to maximize corporate/billionaire profits, how do they pay taxes for the billions this would cost annually per country? Will the billionaires really cover this, as I've seen suggested by some geoengineering proponent?) showering down to join the unlimited industrial/military pollution/destruction of the TPP corporate coup, even without nukes involved, how long will life last? Health will be gone long before, of course...