What dataset should I choose? The influence of data choices on flood exposure estimations at national scales

There are currently several large-scale gridded archives available for the study of flood exposure, and the results will inevitably depend on the datasets included in the analysis. The purpose of this work is to demonstrate how country flood exposure, here represented as the presence of population within floodplains, is influenced by dataset choices.

We conduct this geographical analysis in two parts. First, we conduct a global analysis showing how different flood exposure metrics influence comparisons between countries. Second, we overlay five commonly used gridded archives (three population archives and two floodplain archives) for 32 countries. The purpose is to quantify the influence of data choices, while also giving an overview of the various dataset methodologies. We finally zoom in on areas where the five datasets yield very dissimilar results, to exemplify typical differences among the datasets.