Father and son, on the road. (Image courtesy the Weinstein Company)

At long last, the big-screen adaptation of “The Road” is in theaters. While I’ve not yet had the opportunity to see the movie for myself, I have a great deal of love for the original novel. Relatively upbeat for a Cormac McCarthy yarn, it is of course the story of a father and son’s trek across a bleak, ravaged and destitute post-apocalyptic America.

While McCarthy avoids dwelling on the events responsible for the grim new world the characters endure, there’s definitely some science to the tale — just underneath all those elegant layers of heartbreak, ruin and biblical allegory.

Nuclear Winter: This is the big one. The world, as depicted in the book and film, is one of endlessly overcast skies and mile upon mile of dead vegetation. The implied cause is some sort of large-scale nuclear war.

The theory is that the resulting smoke from burning cities and forests would rise up into the atmosphere and blot out the sun. In the grimmer scenarios, we’d be talking twilight at noon. The environmental ramifications would be pretty severe as global temperatures would plummet and photosynthesis would fail, resulting in wide-scale death from starvation. That’s the short and sweet version, but I implore you to read What will nuclear winter be like? for a far more in-depth analysis. Here’s a particularly scene-setting quote from the book:

“It took two days to cross that ashen scabland. The road beyond fell away on every side. It’s snowing, the boy said. He looked at the sky. A single gray flake sifting down. He caught it in his hand and watched it expire there like the last host of Christendom.”

Nuclear Fallout: The characters in “The Road” have a bit more to contend with than the catastrophic failure of the world’s plant life. If that weren’t enough, there’s radioactive fallout. This theorized bit of nuclear collateral damage actually predates that of nuclear winter, but it also has a lot to do with the cycle and flow of the Earth’s atmosphere. A nuclear blast also spreads dangerous radiated particles over a wide area and can even eject them up into the jet streams, where they drift even farther. Take a look at this distribution model and imagine radiation sickness on such a scale.

As I reported for Discovery News, there’s also been a great deal of study in how nuclear fallout might spread in a metropolitan environment, where tall buildings act as launch ramps for clouds of radioactive particles and where sun-heated concrete and steel creates localized updrafts. Add in accidental radiation shielding and absorption, as well as the blast damage from the detonation and you have quite a terrifying picture of urban horror. In researching the issue, I couldn’t help but be reminded of this line from the novel:

“[…] and the cities themselves held by cores of blackened looters who tunneled among the ruins and crawled from the rubble white of tooth and eye carrying charred and anonymous tins of food in nylon nets like shoppers in the commissaries of hell.”

Yep, and I’ll say it again, this is actually one of the cheerier McCarthy novels. But as my pal Bill Phillips likes to point out, Cormac had to craft a world this bleak and doomed to accommodate a tale so comparatively positive about the human condition.

As for the film, I look forward to seeing it. Some of the reviews are erasing the Michael Bay-esque cheesiness of this wretched trailer, which attempts to repackage the picture to appeal to just about the lowest common denominator.