Human actions accelerate climate-driven floods and droughts

A study of more than 2,000 streams around North America found that those altered by human activity are at greater risk of flooding.

The study from the University of Waterloo analyzed the seasonal flow patterns of 2,272 streams in Canada and the U.S. and found that human-managed streams -- those impacted by developments like dams, canals, or heavy urbanization -- had significantly different flow patterns compared to streams in natural watersheds.

Greater flow increases in managed watersheds indicates more severe flooding -- possibly as a result of the increased paved surfaces in urban regions. Flow dampening on the other hand can lead to water shortages and a loss in biodiversity in managed streams.

The study used natural watersheds untouched by human activity to measure the impact of climate change on streamflow. Using them as a baseline, the researchers then compared flow in managed streams within a radius of 115 kilometers to measure the impact of human developments.