From above, we see an all-new perspective on the flows of air and water that shape our world. Although they look like abstract art, these aerial photographs of Namibia by Leah Kennedy show rippling dunes and spreading fingers of water. Linear dunes like these grow when the prevailing winds are always from the same direction. Over time, rivers meander, always seeking new drainage paths. Patterns like these are probably driven by periodic flooding. (Image credit: L. Kennedy; via Colossal)