Slightly over half of Earth's sixty four million kilometers of rivers and streams run dry for part of the year.
Researchers studied years of water flow in over five thousand locations globally, and combined that information with the weather and geography of that area.
The new research improves river management and wildlife conservation.
Many species have adapted their lives to the periodic presence and absence of water. These rivers also provide food and water for people and help control water quality. In fact, over half of the world's population lives close to such rivers.
Climate change and our own careless use of lands and rivers will cause more and more rivers to stop flowing or flowing way less in the coming years.
So far, we have tried to conserve rivers that flow all year long. But this study shows that there are other rivers and streams that need protection.
Original article:
Most rivers run dry - now and then
Original study: