Can Quasi‐Periodic Gravity Waves Influence the Shape of Ice Crystals in Cirrus Clouds?

The present work, for the first time, unravels the impact of mesoscale gravity waves on the microphysical changes in cirrus clouds over the subtropical Indian region using Raman lidar, satellite, model simulations, and reanalysis data sets. The cirrus clouds are formed from the convective outflow of large‐scale convergence zone extending from south‐west to north‐east Indian region. These clouds are modulated by the upward propagating gravity waves with time periods ~40 and ~20 min over the Raman lidar observational site. The wave‐induced enhancement of moisture leads to supersaturation thereby controlling the ice crystals' size and shape through depositional freezing. The ice crystals size increases, and they transform to irregular shapes in the presence of wave activity. Therefore, the present work is novel and will have implications toward the uncertainties associated with cirrus clouds in both regional and global climate models. Key Points First observational study of the cirrus clouds over the subtropical Indian region using Raman lidar, satellites and reanalysis Imprint of wave activity on the shape of ice crystals Interaction of mesoscale gravity waves with microphysical properties of cirrus clouds