Long-term regional droughts are, unfortunately, a common occurrence on our little planet. Typically though, only droughts that are long-term in their duration are reported on, giving us the impression that the problem is relegated to particular geographies, and not generally widespread. However, a new study from the Netherlands has incorporated short-term droughts into the picture, revealing water scarcity as a much more widespread problem.

This new study, conducted at the University of Twente, created a map of the planet showing regions that were affected by fresh water scarcity for one month or more. Previous surveys would gather data based on an annual basis, ignoring seasonal droughts that are experienced by many regions across the planet, shortages that still cause problems for affected populations, agriculture and the local ecology.

These short-term shortages are typically taken for granted by society at large — it’s not considered a drought if the rains come back in a few months — but humans cannot survive past a few days without drinkable water, and other aspects of life, such as food production, can grind to a halt. The picture painted by the map revealed a shocking number in terms of the amount of people affected: more than four billion people — over half of the planet’s population — are affected by severe water shortages for a minimum of one month out of the year.

While we have the technology to transport fresh water from one region to another, doing so might wind up being an issue of moving the problem around and imposing the shortage on another region, rather than actually solving the problem. “You can still get water from somewhere, but it might mean you get it from a really important ecosystem that dries out and dies while you are swimming in your swimming pool,” explains water researcher Jacob Schewe, from Germany’s Potsdam Institute for Climate Impact Research.