A drought is the result of little or no rainfall occurring over months, years, or longer time periods, causing general suffering of creatures and damage to the environment. Drought can cause crops to fail, water levels to lower, and can decimate animal populations causing an upset in the natural balance. As a culmination of these effects, drought can lead to diseases spreading amongst the population, famine, fires due to aridity of land, and dust storms.
For a region that doesn't rely on rainfed agriculture but draws its water from oases, cenotes, lakes or rivers, an increase in demand (perhaps due to a population boom or a new crop or technology) can exhaust the available supply and cause a de facto drought, rain or no rain. This may be what caused the downfall of at least one Pre-columbian civilisation in Central America. This sort of thing could even lead to mysterious lost cities - sooner or later the aquifer (or whatever) re-fills but the civilisation that built it is gone: either completely eradicated or emigrated or just so degenerate as to be no longer recognisable, squatting in the cities built by their "god like" ancestors.
Conversely, a city built during a prolonged drought (say, an ice age) could find itself suddenly very damp indeed when the water level returns to "normal".
Game and Story Use
- Drought being the people-mover that it is, could overrun a neighboring region with unwanted refugees, causing general unrest amongst the people of the area. Riots, protests, food shortages and intolerance may ensue.
- Indeed, you can use something similar as the basis for an entire campaign - a change in weather patterns might well set off an Age of Migrations in your world on a par with the Dark Ages or the Mongol invasions.
- Conversely, a drought that could be easily managed in peacetime may become a major disaster when the nation that it strikes is already involved in a war.
- Drought could be used as divine retribution against an enemy country or people; thus rendering the area easily conquerable and nearly worthless (in value of resources), cementing it as little-desired and thus easily protected.
- The other great way of creating - or more accurately of simulating - a drought is to destroy a pre-existing irrigation system: there are areas of the Middle East that never recovered from the destruction of the Persian built irrigation systems by the Mongols and Afghanistan today suffers from the damage that nearly forty years of war has done to an irrigation system of similar age. Saddam Hussain's drainage of the swamps of Southern Iraq to suppress the revolt there probably counts as something similar as well.