A large-scale nuclear winter would trigger a global famine. A disaster expert has put together a doomsday diet to save humanity.
It is easy to predict the effects of a nuclear disaster winter. First, why otherwise what would futurologists be for? Second, because the past teaches.
Two centuries ago the largest volcanic eruption in recorded history pushed millions of people in North America and Europe to the brink of famine.
In 1815 Mount Tambora exploded in Indonesia, pumping dust, ash and sulfur dioxide into the atmosphere. The explosion triggered freezing temperatures in the summer of 1816, which destroyed crops and vegetation. The birds fell dead by the millions from the sky. Desperate for food, people started eating raccoons and pigeons.
The period became known as the "volcanic winter" or "year without summer". On average, the global temperature cooled by nearly 18 degrees in tropical regions.
David Denkenberger, a mechanical engineer from the University of Alaska, often uses this eruption as an example when people ask him what would happen in the event of a nuclear winter.
"This is certainly a historical precedent", says the scholar. "But it's hard to get people to think about these bigger disasters."
Denkenberger manages ALLFED, a non-profit organization that intends to identify ways to protect the global food supply during a global catastrophe.
In the event of a nuclear catastrophe, he said, harvesting foods like mushrooms, algae and even sugar from the leaves could help create a sustainable "disastrous diet".
Nuclear winter could wrap the world in darkness
Several researchers predict that one large-scale nuclear war between India and Pakistan (which are both expanding their nuclear arsenals) would cause 250 100 kiloton weapons to detonate. Each more than six times larger than the "Little Boy" atomic bomb dropped on Hiroshima.
An extreme scenario, in which a cloud of black soot would envelop the sky and block the sunlight, causing a sharp drop in temperatures. The main agricultural centers could lose the ability to cultivate, triggering a global famine.
"It would be a dramatic but above all immediate climate change"said Alan Robock, author of a recent study on the effects of a nuclear war between the two countries. "As horrible as the direct effects of nuclear weapons would be, the indirect effects on world food would be much worse".
Small survival manual for a nuclear disaster
Denkenberger says, however, that there are ways to support us, even if the earth becomes burnt and the ice cold falls.
A paper published in 2008 showed how fungi can survive both a thermonuclear nuclear disaster and the ensuing climate.
The conclusion of the document was: "When humans become extinct, the world will be populated by mushrooms."
Mushrooms and algae can grow without much light
Even if a nuclear winter destroyed trillions of trees, the fungi could feed on that dead matter, creating a regenerative food source that it could potentially feed everyone on the planet for about three years, according to Denkenberger estimates.
Since mushrooms do not rely on photosynthesis, they can survive without too much light. The same goes for algae, now studied "only" as a basis for biofuels.
Seaweed is a really good source of food in a scenario like this. It tolerates low light levels and grows quickly.
To feed everyone on the planet, Denkenberger estimates that the world would need around
1,6 billion tons of dry food per year. Humans could potentially grow that amount of algae, he said, in three or six months.
The disaster diet
To get the right nutrients to ward off disease, however, humans cannot rely on a single food source (or two). For this Denkenberger has put together a chart with a real "disaster diet". He illustrated what a typical 2.100-calorie diet might look like in a post-apocalyptic scenario.
The diet includes a mixture of meat, eggs, sugar and mushrooms. It also includes dandelions and tea made from pine needles, which contain vitamin C. A provide vitamin E, which is important for brain function, bacteria would think.
Denkenberger plans to study other natural food sources that could grow near the equator, where there would still be some sunlight after the disaster (although the temperature would still be low).
Surviving and surviving potatoes
"One of the things I learned when moving to Alaska is that even in areas where summers are so cool that trees can't grow, you can actually grow potatoes."he said.
Their leaves also contain cellulose fibers which could be converted to sugar. This process already occurs in biofuel plants, which convert cellulose into sugar to produce ethanol.
Nuclear disaster: the cost of a post-disaster diet
If the global agricultural system were to collapse, Denkenberger said, current dry food stores could feed about 10% of the world's population for five years. This, of course, is insufficient.
The cost of these supplies would also increase due to the demand: "I fear that the price of food would rise so high that a billion people would not be able to afford food".
Storing large quantities of food before a disaster would also be expensive. Denkenberger said such an effort "would cost trillions of dollars and take a long time". Alternatively, dried seaweed can be produced for around € 2 per kg; this is the lowest reasonable cost for dry food in a disaster scenario.
That means it would take about $ 3,2 trillion to produce enough seaweed to feed everyone on Earth for a year - a price that, he added, almost everyone in the world could afford to pay.
There are creative ways to make protein out of thin air
Denkenberger has proposed some technological solutions for the cultivation of food that cannot be stored.
La Unibio, based in Denmark, is already developing a way to convert methane into a highly concentrated protein that can be dried and packaged in (fish) food.
Even the Silicon Valley-based company, Calysta, uses gas such as nitrogen and methane to feed fish and livestock. In a catastrophe, Denkenberger says, those proteins could also be used to feed humans in the event of a nuclear disaster.
Difficult to experience Soleina, protein produced from the air by a Finnish startup, can come in handy. Without so much sunlight, the production process would be too expensive and ineffective. Denkenberger is working on a NASA-funded project that studies how to heat coal without oxygen. The heating process would produce hydrogen and carbon dioxide to be converted into proteins.
These solutions could help even after other disasters
Denkenberger said that agricultural and government workers are more concerned about disasters like hurricanes than a large-scale nuclear winter.
He thinks that some of his solutions, such as extracting sugar and protein from the leaves, can be applied to feed people during a local catastrophe. But it is also possible to store enough food for a serious disaster such as a nuclear war between India and Pakistan.