Early Warning Systems (EWS) are measures designed to reduce the damage potential from natural hazards by providing timely warnings and facilitating the evacuation of at-risk populations. As defined by the United Nations Office for Disaster Risk Reduction (UNDRR), an EWS is ‘an integrated system of hazard monitoring, forecasting and prediction, disaster risk assessment, communication and preparedness activities systems and processes that enables individuals, communities, governments, businesses and others to take timely action to reduce disaster risks in advance of hazardous events.’ 

While monitoring systems are limited to data collection, EWS are complex systems, involving not only technical, but also social, political and even juristic aspects (NDMA, 2020). They are based on four key elements: risk knowledge, monitoring and warning service, dissemination and communication, and response capability (UNDP, 2018) (Figure 1).

The World Meteorological Organization’s (WMO) initiative for ‘Early Warnings for All’ launched in 2022 underlines the importance of EWS as life-saving protection from hazardous hydrometeorological, climatological and related environmental events.

A key aspect of Glacial Lake Outburst Floods (GLOF) early warning is its activation only once an event has occurred. This means that the warning times for downstream communities are typically in the range of minutes to a few hours,  unlike other hydro-meteorological warning systems, e.g., for riverine flooding, that are based on event forecasts or predictions and may provide days of advance notice. However, in contrast to purely structural GLOF DRR measures, GLOF EWS are often less cost-intensive and more flexible to use as they can reduce the risk not only of GLOF events in very specific locations, but also of other mass movements in the context of a larger catchment area. This makes EWS an efficient and effective measure to reduce the risk stemming from GLOFs in Central Asia.

The GLOFCA project is instrumental in enhancing the region’s capacity to monitor and assess glacial lake hazards and implement early warning systems at priority sites. Beyond the conventional warning signals like sirens or SMS alerts, the project emphasizes the importance of the “soft” components of EWS—awareness-raising, educational programs, and preparedness activities. These ensure that local populations know how to respond, have necessary provisions, and understand the protocols involving various institutions, such as the military and local authorities, during a crisis. Moreover, the systems established for GLOF risks also provide benefits for other natural hazards like landslides and earthquakes, underscoring their critical role in regional disaster risk reduction.