The UN goal: early warnings for everyone by 2027
The United Nations Early Warnings for All initiative, launched in 2022, set the ambitious goal of ensuring that every person on Earth is covered by an early warning system by the end of 2027. As of 2026, significant progress has been made — but significant gaps remain. An estimated one-third of the world's population, concentrated in least developed countries and small island developing states, still lacks access to adequate early warning systems.
The initiative focuses on four pillars: disaster risk knowledge, detection and monitoring, dissemination and communication, and preparedness to respond. Technological capability for detection exists for most hazard types. The persistent gaps are in the last mile — getting warnings to people who need them in time for them to take protective action.
Earthquake early warning: seconds matter
Japan's earthquake early warning system remains the gold standard, capable of providing 5–30 seconds of warning before strong shaking arrives at locations distant from the epicenter. The ShakeAlert system on the US West Coast, which became publicly operational in 2021, has matured through multiple real events and demonstrated that even a few seconds of warning enables protective actions — drop, cover, and hold on — before shaking begins.
The fundamental limitation of earthquake early warning is physics: seismic waves travel at 3–8 km/s, so warning time depends on the distance between the earthquake source, the nearest seismic station, and the warning recipient. Communities near the epicenter may receive no warning before the strongest shaking arrives. Despite this limitation, the systems demonstrably save lives by enabling automated responses: stopping trains, opening fire station doors, alerting surgical teams, and triggering industrial shutdowns.
Tsunami warning: mature but uneven
The Pacific Tsunami Warning System has operated since 1949 and now provides comprehensive coverage across the Pacific basin. The Indian Ocean Tsunami Warning System, built rapidly after the 2004 disaster, is operational but faces ongoing challenges with maintaining buoy networks and ensuring coastal communities can receive and respond to warnings.
The Caribbean and Mediterranean regions remain less well-served by tsunami warning infrastructure despite significant tsunami hazards from both seismic and volcanic sources. The 2022 Hunga Tonga event highlighted unexpected warning gaps — the atmospheric-wave-triggered meteo-tsunamis it generated were not covered by existing warning protocols, prompting ongoing revisions to warning system capabilities.
Severe weather: expanding coverage, persistent gaps
Tropical cyclone forecasting has improved dramatically — 5-day track forecasts today are as accurate as 3-day forecasts were 20 years ago. Satellite monitoring ensures that no tropical cyclone goes undetected, even in ocean basins without aircraft reconnaissance. However, intensity forecasting (predicting how strong a storm will be) remains challenging, particularly for rapid intensification events.
Tornado warning lead times in the US average 13–15 minutes, but many developing countries in tornado-prone regions have no tornado warning capability at all. Flash flood warnings depend on real-time rainfall monitoring and hydrological modeling that many countries lack the infrastructure to support. The technology exists — the gap is deployment and maintenance in resource-limited settings.
Technology trends closing the gap
Several emerging technologies are helping close early warning gaps. Cell broadcast systems, which push alerts to all mobile phones in a target area without requiring app installation, are being deployed across more countries. Satellite-based internet and communication systems can reach remote areas without terrestrial infrastructure. Machine learning is improving the speed and accuracy of earthquake detection, flood forecasting, and fire weather prediction.
Low-cost seismometer networks, IoT-based environmental sensors, and smartphone-based detection are expanding monitoring coverage in developing countries at a fraction of the cost of traditional instrumented networks. These approaches trade individual sensor precision for network density — and for many hazards, more sensors at lower precision outperform fewer sensors at higher precision.