A Quantitative Analysis of Satellite-Observable Storm Top Features

Satellite infrared imageries of storms often show some distinct brightness temperature features, such as cold-v (enhanced-V) and localized warm area. Many theories have been proposed to explain the formation of these features but uncertainties linger. In fact, storm top IR features must have been caused by the combination of multiple mechanisms. A new approach is proposed to resolve the complexity. This study will decompose the contributions of the temperature features. A cloud-resolving model will be used to simulate the temperature distribution at the storm top. We will show that the simulated storm top temperature field exhibits all major IR features observed by satellites. We will then determine the contributions by different physical mechanisms responsible for these features. We will show that the adiabatic process is the most important factor responsible for the observed features but other mechanisms, such as turbulent mixing, also contribute. The result of this study will clarify the mechanisms about the IR storm features and will provide clues for diagnosing atmospheric variables of storms and their surrounding environments using satellite observations.