Climate Change Boosts Extreme Weather, Increasing U.S. Flood Risks

As global temperatures rise, the U.S. is experiencing more intense and frequent extreme precipitation events, leading to heightened flood risks. From 1958 to 2021, the most extreme precipitation days have seen a significant uptick, with the Northeast and Midwest witnessing increases of 60% and 45%, respectively. This trend is projected to continue, with 85% of U.S. counties expected to see at least a 10% increase in precipitation on the heaviest days under a 2 degree (C) warming scenario.

Alaska and Hawaii could face some of the largest increases in extreme precipitation, with rises of up to 43% and 30%. The intensification of these events poses severe risks to people, infrastructure, and ecosystems, particularly in areas with outdated flood management systems. Increased moisture in the air due to warming—4% more for every 1 degree (F) rise—enhances the potential for heavy downpours, exacerbating flash flood and landslide risks.

The financial impact is also staggering, with inland flooding causing over $230 billion in damages from 1988 to 2021, a significant portion of which is attributed to climate-driven changes in precipitation patterns. With ongoing climate change, these challenges are expected to worsen, underscoring the urgent need for enhanced resilience and mitigation strategies.