Early warning
One of the most effective responses to human vulnerability to environmental change is to strengthen mechanisms for early warning. Many actions can be taken to protect life and property if warning is received in time. While some threats are inherently unpredictable, many of those arising from threats from environmental degradation and mismanagement, and from human activities, can now be anticipated with some precision. Early warning capacities are increasing steadily with technological advances in environmental observing, assessment and communications. Examples are the cyclone early warning systems that have been established in India and Mauritius.
| Advantages of foresight: predicting El Niņo |
| Forecasting El Niņo events can help countries with their strategic planning to ensure security in areas such as agriculture, fishing, water resource management, flood control and energy supply, thereby reducing the vulnerability of the people and country. The Tropical Atmospheric-Ocean (TAO) array of ocean observation buoys, using measurements of surface sea temperature, helps provide the first indication of an El Niņo six to nine months ahead of the event. A number of institutions in Peru, including the Instituto Geofisico, are working together to improve predictions of El Niņo events using statistical modelling. Such forecasts of rainfall and hot and cold events have helped farmers to plan better use of water resources for irrigation, and fishermen to prepare better for variations in fish stocks. Forecasts of the next rainy season are issued in Peru each November, after which farmers' representatives and government officials meet to decide the appropriate combination of crops to plant. A forecast of El Niņo weather will mean recommendations to plant crops that prefer wet conditions, such as rice, and to avoid crops that prefer drier weather. Australia, Brazil, Ethiopia and India are some of the countries that have taken similar initiatives. |
| Source: NOAA/PMEL/TAO 1998, IOC 1998, CNA Peru 2001 |
Conventionally, early warning means an urgent indication of an impending hazard (ISDR Secretariat 2001). There is a need for both sudden onset warnings, for imminent disaster threats such as tropical storms and floods, and slow onset warnings for disseminating information about disasters that may develop over time such as famine and drought.
The term early warning is often taken to mean prediction' when in fact the occurrence of many threatening events is essentially unpredictable. Early warning simply means that an event is imminent and the time to escape from it or take action against it is now. Early warning information can be produced in the context of a broader vulnerability assessment process, which includes the production and communication of forecast information and the incorporation of that information in user decisions.
To be effective, an early warning system must be able to stimulate a timely response before an event takes place. It must identify who are the users of early warning information and what is the most efficient way to reach them with credible information to enhance their powers of decision-making. It must then translate relevant data into early warning indicators that decision-makers can easily interpret and use.
Ultimately, the single most important factor that will lead governments to incorporate the use of early warning systems and information in decision-making is the political will to invest in response systems, both nationally and internationally (Buchanan-Smith 2001). One example of an operational early warning system which has generated such a response is the Famine Early Warning System Network for Africa (see box).
