An early warning works only if the hazard is detected, the forecast is good enough, the message reaches people in time and they know what to do. Each link can fail, and the last mile, from warning to action, often fails most. The Global Centre for Risk and Innovation (GCRI) studies warning science, forecast verification, communication and last-mile limitations, in support of the public authorities that alone have the mandate to issue warnings. This page is part of science and methods.
GCRI · Institution · service level R0
Early warning research at GCRI studies the four links a warning depends on: detecting the hazard, forecasting it well enough, reaching people in time and their knowing what to do. Each link can fail, and the last mile from warning to action often fails most; GCRI supports the authorities that alone issue warnings and issues none itself.
Where response must travel furthest from a large city, with the roads, airports and ports that carry relief, shown for Mozambique and Malawi as an example geography for this subject.
Knowing which hazards threaten whom, and how badly.
Observation and forecasts with verified skill, using forecasting and time-series analysis and Earth observation.
Messages that reach everyone at risk, in languages and formats they can use, including people with disabilities.
People who understand the warning, trust it and can act on it.
Research focuses on the links where warnings most often fail, and on evidence that agencies can use to improve their own systems.
Measuring forecast skill, false alarms and missed events against observations.
How wording, channel and trust affect whether people act.
Groups and places that warnings do not reach, and why.
Each term as this page uses it. Where a standard-setting body defines the term, the wording follows that body.
| Term | Definition |
|---|---|
| Early warning system | An integrated system of hazard monitoring, forecasting, risk assessment, warning communication and preparedness that lets people and institutions act before a hazard strikes, in UNDRR terminology. |
| Impact-based forecasting | Forecasting that describes the expected effects of weather on people and assets. |
| Last mile | The final step in which warnings reach the people at risk. |
| False alarm ratio | The share of warnings issued that were not followed by the warned event or impact. |
The current service level is R0: information and enquiries. An enquiry receives a reference and names the next step; applications, payments, compute allocations and registrations open only when their team, terms and review capacity exist.