In a world where natural disasters and health crises often catch us off guard, leading to unexpected catastrophic impacts, the need for a forward-thinking mindset has never been greater. Embracing the philosophy of ‘Expect the Unexpected’ is no longer merely an optional addition but an absolute imperative for facilitating resilience and well-being, especially in marginalized communities. Responsible GIScience, driven by burgeoning geospatial big data (e.g., data from social media, mobility, and crowdsourcing), cutting-edge technologies (e.g., GeoAI, CyberGIS, and digital twins), and responsible thinking, equips us with a diverse array of tools and channels to accurately and comprehensively monitor and predict varied, unforeseen societal impacts and human needs during hazardous events. This talk will delve into the theory, methodologies, and real-world applications of harnessing geospatial big data from various sources to uncover the unforeseen, disparate societal impacts and human needs triggered by natural disasters and health crises.