Drought can amplify floods, but sometimes help prevent them
Drought and floods are usually viewed as separate disasters, but the research of researcher on hydrological extremes and multi-risk dynamics in humanitarian contexts, Alessia Matanó, shows that they are much more closely linked than is often thought. In fact, how an area experiences a drought can have a major impact on the severity and timing of floods that follow.
Matanó examined the interplay between hydrological processes and human behavior during extreme weather events. In doing so, she looked at how drought affects the dynamics of subsequent floods - not only in soil and hydrology, but also in society.
Drought can change soil properties
The study shows that drought can change soil properties, causing rainwater to be absorbed and drained differently. As a result, floods can occur more quickly or take a different course than existing models predict. According to Matanó, many current hydrological models do not adequately account for these complex and changeable processes.
In addition, human behavior plays an important role. During droughts, communities often adjust their water use, farming methods and natural resource management. Such adjustments can later have unexpected impacts on flood risks - both positive and negative.
A striking conclusion from the study is that multiple extreme events do not automatically lead to greater damage. In some situations, successive or simultaneous hazards may actually mitigate each other. This depends heavily on local topography, water resources and social conditions.
Opportunities for smarter water management
The research findings have important implications for future water and risk management. Matanó : "Drought and flood policies need to be much better coordinated. Now these risks are often still dealt with separately by different agencies and within separate policy frameworks." The findings also point to opportunities for smarter water management. For example, excess water during floods can be used strategically to replenish groundwater, making regions better prepared for future droughts.
At the same time, Matanó emphasizes that risk management must remain practical. Systems where multiple hazards converge are complex, but policymakers and emergency services need clear and useful tools to make quick decisions. With climate change making both droughts and extreme precipitation more common, Matanó underscores the need for an integrated approach to water and disaster management.
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