A new study has concluded that if Russia and the United States start a hot war, 5 billion people will die of famine alone. The new study in the journal Nature Food projected the amount of soot that would be thrust into the Earth’s atmosphere in a variety of nuclear war scenarios, and none of them are good.

Scientists at Rutgers University studied the potential soot levels from smaller exchanges between India and Pakistan to a full-blown war between Russia and the United States. A relatively modest Indo-Pakistani war would slash the world’s average caloric output by 7% within the first five years. That’s bigger than any disruption humanity has faced thus far. “Even for a regional nuclear war, large parts of the world may suffer famine,” said the study’s authors.

According to a report by ZeroHedge, the biggest US-Russian exchange would positively devastate global food production, shrinking it by 90% within three to four years after the explosions cease, the researchers say. Seventy-five percent of human beings would be dead in two years from starvation.

As devastating a picture as the study presents, it’s likely understated. “The ozone layer would be destroyed by the heating of the stratosphere, producing more ultraviolet radiation at the surface, and we need to understand that impact on food supplies,” Rutgers assistant research professor Lili Zia tells Sky News. Researchers also didn’t factor in changes in fertilizer and food supplies, which would be substantial.

While the Rutgers study has a generally horrific backdrop, one country stood out as faring far better than others: Australia’s caloric output showed only small reductions or even an increase. But that’s where the good news ended. The researchers said Australia would be besieged by starving refugees from Asia.

Noting that crises “with nuclear undertones are festering,” earlier this month, United Nations Secretary-General Antonio Guterres warned that mankind is “just one misunderstanding away from nuclear annihilation.”

In the immediate aftermath of Russia’s February invasion of Ukraine, President Vladimir Putin said he’d ordered his nuclear forces into “special combat readiness.” But it isn’t just Russia that’s a concern. The U.S. is also in heightened tensions and seemingly provoking an all-out war with another nuclear power. As The New York Times reported in June:

Last summer, hundreds of new missile silos began appearing in the Chinese desert. The Pentagon declared that Beijing, which had long said it needed only a “minimum deterrent,” was moving to build an arsenal of “at least” 1,000 nuclear arms by 2030.

Just when things were quieting down after House Speaker Nancy Pelosi’s visit to Taiwan, a previously-unannounced delegation of five more pathetic, attention-seeking legislators arrived on the island on Sunday. That provoked more Chinese anger and another round of military drills near Taiwan.

If seems like in this scenario, all you’d need to do is stockpile some food, but prepare for other issues, such as radiation and surface water contamination. Be knowledgeable on how to keep radiation out and what to do if the worst-case scenario: nuclear war, breaks out.

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