Tropical Cyclone Carina appears as a tightly wound spiral in the Indian Ocean in this satellite view of the storm, obtained by the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on NASA’s Aqua satellite on February 27, 2006. Carina had become an organized storm system four days earlier, and built rapidly into a powerful cyclone. By the time MODIS obtained this observation of Carina, peak winds were blowing at 96 knots or 110 miles per hour (1 knot = 1.15 mph). However, the tropical cyclone was moving into the southern Indian Ocean well away from the nearest land, even the very remote Cocos Islands several hundred kilometers east. Tropical cyclones are large, rotating regions of wind, clouds, and thunderstorms formed over warm tropical oceans; a similar storm (of sufficient strength) in the Caribbean basin is called a hurricane. While tropical cyclones are often highly destructive in terms of human lives and property, they form an important part of the biosphere by transferring heat energy from the tropics to the mid-latitudes and polar regions.