Floods, droughts, and rainfall-induced landslides are hydro-geomorphic hazards that affect millions of people every year. Anticipation, mitigation, and adaptation to these hazards is increasingly outpaced by their changing magnitude and frequency due to climate change. A key question for society is whether the research we pursue has the potential to address knowledge gaps and to reduce potential future hazard impacts where they will be the most severe. We use natural language processing, based on a new climate hazard taxonomy, to review, identify, and geo-locate out of 100 million abstracts those that deal with hydro-hazards. We find that the spatial distribution of study areas is mostly defined by human activity, national wealth, data availability, and population distribution. Hydro-hazards, which impact large numbers of people, increase research activity, but with a strong disparity between low- and high-income countries. We find that a 100 times higher impact is needed before low-income countries reach comparable research activity to high-income countries. This "Wealth over Woe" bias needs to be addressed by increasing research on hydro-hazards in highly impacted and under-researched regions, or in those sufficiently socio-hydrologically similar. We urgently need to reduce knowledge base biases to mitigate and adapt to changing hydro-hazards if we want to achieve a sustainable and equitable future for all global citizens.