Photos

The image shows wave clouds rippling over a fire-speckled Central African Republic landscape. Wave clouds typically form when a mountain, island, or even another mass of air forces an air mass to rise, then fall again, in a wave pattern. The air cools as it rises, and if there is moisture in the air, the water condenses into clouds at the top of the wave. As the air begins to sink, the air warms and the cloud dissipates. The result is a line of clouds marking the crests of the wave separated by clear areas in the troughs of the wave. Each red “hotspot” marks an area of actively burning fires deliberately set to manage the land. Image courtesy of NASA/ Jeff Schmaltz.