As reported in Wired, scientists at the University of Hong Kong collected data on “14 variables, such as human height, the price of gold, tree ring width, and temperature from pre-industrial Europe between the years 1500 and 1800” to determine whether periods of climate change had a causal relationship with conflict. After performing a Granger causality analysis for time periods of 40 to 150 years, they determined that climate change was a statistically significant cause of social disturbances, wars, migrations, epidemics, famines, and nutritional status, as reported in the Proceedings of the National Academy of Sciences. What’s more, climate “caused famines, economic downturns, and catastrophic human events far more often than did any of the other 14 variables.”
As climate changed for the worse, agriculture often suffered, leading to an increase in the price of gold and inflation. Failed crops could lead to famine, which could makes plagues far worse (because a malnourished person is more likely to die). Malnourished people often are more stressed, which could lead to political instability or war. Scientists were even able to use their model to determine a “climate change crisis threshold,” beyond which a crisis of some sort would occur. The model proved historically accurate. But as climate then changed for the better, the scientists often saw times of peace, health, and prosperity.
But some have criticized the model. The model ends at 1800. The research team is unsure if the model would still hold for an industrialized world filled with societies less sensitive to climate change (due to better trade, technology, and social factors). The team is also unsure if the model would hold for recent times, as climate change has accelerated. Others have criticized the model for overlooking other factors such as religion, trade, and exposure of the New World to the diseases of the Old World. Others note that the model considers only temperature change, not other weather-related factors such as rainfall.
For the most part, fictional worlds tend to have one climate. Think Tatooine (desert), Hoth (ice), and the second moon of Endor (forest) in the Star Wars movies. While terrain in Middle Earth changed, the climate did not. Even fictional worlds that have some variation in climate (cold in the north, warm in the south, say), the distinctions between those climate zones are usually sharply drawn and remain the same over the course of the story.
Of course, there are exceptions. In Robert Jordan’s Eye of the World series, the world does experience some climate change as the Dark One exerts his influence on the world. Jordan describes how prolonged winter leads to crop failure and famine, and how prolonged summers lead to drought. In George R. R. Martin’s A Song of Ice and Fire series, perhaps the most quoted line is the House Stark words, “Winter is coming.” This phrase carries with it the implication of many crises that the scientists studied (although Martin’s world contains enough crises already). And of course, climate change plays a central role in the Frank Herbert’s Dune saga.
How can fiction writers use this study to inform their stories? What if your story takes place during a period of transition? What if climate change becomes a source of conflict for your characters? What if your fantasy story included famine, plague, wars, or invasions that had climate change as a cause? For example, what if one kingdom launched a war not out of greed but out of desperation for food and water? What if your science fiction story was one of people reacting to the stresses of terraforming a planet (especially if the results are less than satisfactory or result in unintended consequences)? What if your story is about the last gasps of a dying planet? What if your story is about people simply scraping by due to prolonged periods of climate change?
What do you think of this study? How might you use its findings to enhance your writing?