As the atmosphere warms, the water cycle—the process by which seawater evaporates, rains down, and then evaporates again—will intensify. Everywhere, the ocean surface will become, on average, saltier. The extra evaporated water vapor will rain down disproportionately in areas such as the tropics and Scandinavia, bringing stronger storms and more frequent floods. Meanwhile, the areas just north and south of the tropics, which already tend to be saltier than other regions, will become saltier and warmer. In the very saltiest areas, existing "desert" areas—those too salty to host most life—could grow.