Project Idea

Trend analyses in the literature have found little consistency on whether floods have increased or decreased. We are developing new indicators to detect changes in floods that are based on the flood types as well as the time of the year the floods occur, their spatial coherence, catchment soil moisture and land use. Since the indicators identify the flood generating processes they are expected to be more powerful for detecting change than flood magnitudes alone. We will use these new indicators to detect changes in flood characteristics in European catchments.

The exact causes of river flood changes are still a mystery. Although, drivers such as climate and land use change are known to play a critical role, their complex interactions have not been disentangled. We will separately analyse floods in catchments where climate variability is large and land use changes are small, and where the opposite is the case, and will account for the dominant mechanisms of change in flood modelling. The impact of this will be to enable isolation of individual factors contributing to changes in floods for a given flood process type, and make the change mechanisms transparent.

The current approach of assessing how floods will change for a given change in climate or land use consists of model-based scenario analyses. However, it is unclear how accurate the model based approach is. For this reason we will add two independent methods that are based on the temporal and spatial variability of flood data. The impact of this will be to enhance the reliability of the estimated sensitivities of floods to changes in the drivers. Understanding the sensitivities is extremely useful for predicting the impact of future climate and land use changes on floods.