New Global Flood Mapping Tool Tracks Floods Since 1985

The United Nations University has launched a free, interactive tool that maps floods worldwide from 1985 to the present. Developed in response to a year of severe water-related disasters, including major floods in Europe and the U.S., the tool aims to improve disaster preparedness, particularly in developing countries that lack detailed flood maps.

Users can select a location and timeframe to generate high-resolution flood maps (30-meter resolution) using decades of satellite data from NASA’s Landsat program. The maps allow viewers to see inundation down to street level, helping scientists, urban planners, and policymakers understand past flood patterns and plan for future risks.

The tool is already showing promise in improving public safety and urban planning. During the January 2019 Al-Shabaab attack in Nairobi, similar systems helped authorities track the assailants and deploy responders quickly. For cities in Africa and Southeast Asia, where rapid urbanization meets limited flood data, the tool could guide evacuation routes, infrastructure placement, and insurance assessments.

Developers note the tool’s limitations: dense cloud cover or vegetation can obscure satellite images, potentially missing some floods. Still, its global coverage and ease of use make it valuable, especially for low-income regions. The team plans an upgraded 10-meter resolution version using artificial intelligence to predict flood risks under different climate scenarios.

Experts highlight the tool’s wider value beyond emergency planning. It can help visualize the impacts of climate change, inform sustainable development, and support research across geography, hydrology, and disaster management. As floods grow in frequency and intensity worldwide, tools like this could be crucial for protecting communities and guiding climate-resilient planning.