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forecasts in northeast Brazil is that the prediction of a drought raises a set of unpleasant expectations for many in the region. Past governments typically responded to droughts with large-scale relief efforts that included infrastructure projects and emergency food and work projects and that sent relief funds to certain powerful interests and created a sense of dependency in the population. Many policy makers are concerned about drought forecasts because they do not want, nor can they afford, to perpetuate this drought "industry" (Magalhaes and Magee, 1994).

The case of northeast Brazil provides several lessons about the value of seasonal forecasting in a region where drought can have devastating impacts. It demonstrates the ease with which forecasters can lose their nerve, and the public its trust, as a result of an inaccurate forecast such as occurred in 1996, and the implications for subsequent forecasting efforts. It also shows that some farmers are unable to use seasonal forecasts because they do not have the resources or flexibility to respond. Another important insight is that it is important to include economic and political factors such as subsidies in assessing the effects of a prediction for agriculture, in order not to overestimate forecast value and to consider local history in making assumptions about how a forecast will be received.

The Credibility of Famine Early Warning Systems

Seasonal climate forecast information is also used in famine early warning systems. Since the 1970s, the U.S. government has used climate information to anticipate the onset of famine, to target people at risk, to reduce response time, and to estimate food and other relief requirements, especially in Africa (Walker, 1989; Hutchinson, 1998). The U.S. Agency for International Development has had a warning system for Sub-Saharan Africa since 1981, initially based on information about rainfall, vegetation, and crop yields. The key indicator has been a vegetation index, derived from the AVHRR (Advanced Very High Resolution Radiometer) satellite of the National Oceanic and Atmospheric Administration, which provides information about the progress of the rainy season through monitoring the productivity of natural pasture and large-scale agriculture. Forecasts of seasonal agricultural production are made based on past relationships between early season rainfall and yields. The famine early warning systems can be considered a form of seasonal forecasting because they anticipate conditions up to 6 months in advance, through a combination of qualitative assessment and crop predictions.

By the mid-1980s it was obvious that biophysical information needed to be linked to socioeconomic information in order to provide useful famine warning because famine is created as much by social, economic and political conditions as by drought. Thus, the system now couples a wide