A mirage in which the size of an object is magnified. Towering Thunderheads: Extremely tall cumulus clouds whose tops reach the boundary between the troposphere and the stratosphere (tropopause). Created by the surface heating of Earth which results in powerful convection currents. Capable of producing thunderstorms, hence the name. They tend to look like the mushroom clouds created from nuclear blasts over and under water. Strong convection currents caused by the heated land make these thunderheads

mirage in which the angular height of the image is greater than that of the object. As the width is unaffected (the angular width of image width remains that of the object because the refractive index gradient is vertical), the aspect ratio is altered and distant images appear vertically enlarged. Towering often accompanies sinking - distant features appear depressed and enlarged - but it can also accompany looming. Compare stooping.