The FEWS and FEWS NET activities have used remote-sensing satellite data to monitor drought and famine since the late 1980s. NDVI was first used to monitor the green-up period in sub-Saharan Africa and to detect anomalous vegetation conditions. Since 1995, satellite-derived rainfall estimates have been used in a similar manner. Crop performance models have since been developed which use NDVI and RFE data as input. The WRSI crop model is applied to the Sahel, southern Africa, and Greater Horn of Africa regions for a variety of crops during their growing seasons. The RNCD method combines rainfall and vegetation conditions and is applied primarily in the Sahel region.

Remote sensing and satellite-derived products, as well as crop models based on satellite data inputs, will continue to play major roles in future FEWS NET activities. In the ongoing effort to monitor and alleviate food insecurity in Africa, FEWS NET scientists will continue to use satellite data to model and understand long-term trends exhibited in the satellite-derived vegetation, rainfall, and crop performance. Planned activities call for model validation wherever and whenever precious ground data become available. Analyses will also be undertaken to characterize teleconnections relating crop performance in Africa with El NiƱo and other climate indicators.

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