About 300 million people in the United States would be at risk of death from radioactive fallout in the four days following a nuclear attack, according to a new report modeling the potential impact of such a horrific event.
If the United States were attacked with nuclear weapons, an adversary would most likely concentrate all fire on the country’s intercontinental ballistic missile (ICBM) launch sites (silos).
Any retaliatory U.S. attack would originate from these silos in Colorado, Montana, Nebraska, North Dakota, and Wyoming—and their destruction would be the enemy’s top priority.
This is the assumption scientists used to model deaths from a nuclear attack, using the 450 ICBM silos in these states as the epicenter.
The population density in these states is low, but winds could transport the radioactive material widely.
This map predicts the worst-case scenario following a nuclear attack on the 450 ICBM silos in the western United States. This radiation would kill 300 million people
Their maps are part of a special report on the U.S. nuclear program published Wednesday in Scientific American.
And the results are grim: Depending on weather conditions, 90 percent of the population of the lower 48 U.S. states, as well as people in the northern states of Mexico and the most populous regions of Canada, would be at risk of receiving lethal doses of radiation.
Using weather patterns recorded through 2021, scientists simulated the aftermath of an 800-kiloton warhead that hit all 450 silos simultaneously, crippling the U.S. arsenal. First, they mapped how wind patterns would have carried the fallout on each day of 2021.
For the map above, they recorded the worst possible result for each location. In this scenario, three million people living in communities surrounding the silos would risk receiving eight grays (Gy) of radiation in the four days after the attack, resulting in certain death – one Gy is enough to cause radiation sickness to cause.
One Gray (Gy) is the International System of Units (SI) and is equal to 100 units of radiation (rad), which corresponds to an absorbed dose of 1 joule/kilogram – a thermal heat capacity.
The annual radiation limit is 0.001 Gy
The researchers used 2021 weather data to calculate a more conservative estimate: the average risk of radiation exposure on a hypothetical day. “In doing so, they averaged the influence of changing winds on radioactive fallout across the entire continent,” the report says.
This estimate is more conservative than the first, but still predicts that “most residents of Montana, North Dakota, South Dakota, Nebraska, and Minnesota would receive average doses of more than 1 Gy, resulting in deaths from acute radiation syndrome, especially with children”.
Even in this scenario, millions of people would be at risk of dying from radiation.
Symptoms of radiation syndrome depend on the dose a person receives and can include nausea, fatigue, vomiting, diarrhea, skin damage, seizures, and even coma.
With high enough doses of penetrating radiation, these symptoms can appear within minutes and can be fatal.
Scientific American’s editors commissioned the special report because the U.S. government is in the midst of a $1.5 trillion project to refresh its aging nuclear weapons, including those stored in these silos in western states.
Their message is clear: “We should reconsider this abject folly rather than once again squander our wealth while spurring a new arms race.”
This report is not the magazine’s first, but it is the worst yet.
Similar estimates from 1976 and 1988 underestimated the possible extent of radioactive deaths from a nuclear attack on the United States, the authors of the new report said.
Newer weather modeling techniques are allowing scientists to more accurately estimate the spread of precipitation across the continent.
These land-based ICBM silos were originally intended to deter a nuclear attack from Russia or other foreign powers. It was assumed that the possibility of catastrophic retaliation would prevent a nuclear attack.
They also represent ideal targets for a pre-emptive nuclear strike. And if this report’s predictions are correct, such an attack would forever change the population of North America and beyond.