Limitations of current operational systems for extreme hydrometeorological events (Jaime Gaona)

“Limitations of current operational systems based on remote sensing and models for the characterization fo extreme hydrometeorological events” by Jaime Gaona The Open-Earth Monitor Global Workshop 2026 "Next-Generation EO & GeoAI Built on Openness and Distributed Data" 7-9 October 2026, Barcelona, Spain https://earthmonitor.org/global-workshop-2026/ Extreme hydrometeorological extremes are one of the main focuses of operational early warning systems for natural hazards. The ongoing integration of remote sensing datasets into the monitoring pipelines is aimed at contributing to the refinement of the forecasts and the accurate identification of the risks. However, very few studies have specifically addressed the inherent uncertainties of the remote sensing datasets in the range of extreme events. Multiple factors in the processing of these datasets can impact the capabilities of each type of data to effectively detect potentially hazardous events due to unrealistic recognition of the tails of the distribution of events. This study is devoted to the intercomparison of remote sensing, model-based and reanalysis products of key variables of the water cycle (rain, soil moisture, flow) to evaluate the consistency of common current operational products for the portrayal of extreme events. The procedure comprises specific extreme value analysis of the distributions of the datasets with special attention to the characterisation of the magnitude and temporal dimensions of the events. In this way, metrics of frequency, duration and intensity are applied to assess the suitability of each product for proper extremes identification against ancillary data of multiple events of well-known impact. The results indicate relevant differences among products well before the range of true extreme events, which partly explains the struggle of current operational monitoring systems to accurately characterise impactful events. Discussion on the factors influencing such notable differences in the products apprise of multiple aspects of datasets generation and handling that led to distorted capabilities in the tail range of the distributions that need review and coordination between the actors in charge of the generation and application of datasets. The study encourages further attention to the evaluation of data in the range of their most relevant application, risk assessment, in order to avoid undesired inherited constraints to their application, jeopardising the confidence in early warning systems or the remotely–sensed data.