From Observation to Action: the future of EO-Driven Multi-Hazard Risk Assessment

This chapter explores recent advances in the use of Earth Observation (EO) for understanding and addressing climate extremes and multi-hazard risks, based on activities contributing to the European Space Agency's (ESA) Extremes and Disaster Science Cluster. As climate-driven disasters such as floods, droughts, wildfires, and compound events increase in frequency and severity, EO has emerged as a vital tool for monitoring, forecasting, and assessing their impacts. The chapter highlights novel EO-based methodologies and data fusion techniques developed across six ESA-funded projects. These range from uncertainty-aware satellite precipitation datasets to deep learning models for compound heat and drought event forecasting. A key theme is the integration of EO data with in-situ observations, modelling frameworks, and Artificial Intelligence (AI) to better characterize cascading hazard interactions and system vulnerabilities. The chapter also identifies cross-cutting challenges, scientific gaps and emerging opportunities. Finally, it highlights the role of open science, interoperable data systems, and collaborative platforms to foster transparency, usability, and innovation, that together with scientific advancements constitute a foundational element in a new generation of science-informed, AI-enabled, and impact-driven risk assessment tools–helping move from observation to Earth Action in the face of accelerating climate risks.