Lake Chad, located at the borders of Chad, Niger, Nigeria, and Cameroon was once the 6th largest lake in the world. A major drought in the feeder river systems regions has caused a significant drying of the lake. Landsat satellite imagery show the profound effect of the lack of upstream water sources. Lake Chad is also a fairly shallow lake (generally no more than eight m deep); consequently, more rapid decline in the lake surface is more noticeable.
Historic records indicate the drying of the lake has happened frequently over the centuries. Landsat data provide a permanent record of the changes in the past decades and will provide a useful data base for future studies.