The world of Against the Storm is governed by an eternal cycle. Every few decades, a cataclysm known as the Blightstorm occurs, and wipes the entire World Map clean. The only safe haven is the Smoldering City.
The calendar (bar) at the bottom of the screen shows how much time is left before the next Blightstorm. The bar slowly fills up with every settlement you complete or abandon. The Amount of time passed is based on the number of years you spend in a given town. When the bar reaches the end hash mark, you will no longer be able to establish new settlements. The only thing you can do is complete the cycle by clicking on the button next to the bar. Once the Blightstorm starts, the World Map reshapes itself. Settlers take refuge in The Citadel while all settlements are destroyed, biomes are regenerated, and modifiers appear in new places.