Gravity Waves and Turbulence in the UTLS and Their Impact on Tracer Variability as Observed in Recent Airborne Campaigns (Invited Presentation)

Variability in the upper troposphere to lower stratosphere region (UTLS) is influenced by vertical motions on a wide range of scales. While large-scale mean vertical winds in the UTLS are generally well characterized based on our understanding of the general atmospheric circulation, small-scale (<100 km) vertical motions are not well characterized despite their importance on UTLS processes such as cirrus cloud formation and dehydration as well as mixing and transport of trace gases. High-rate vertical winds measured by high-altitude aircraft are ideal for constraining small-scale vertical wind variability in the UTLS. We analyze such data collected by the Meteorological Measurement System (MMS) instrument during the DCOTSS and ACCLIP campaigns over the boreal summer monsoon regions to investigate the impact of gravity waves and turbulence on UTLS composition. Preliminary results indicate that 1 Hz vertical wind variability and turbulence are enhanced near convection and at altitudes near the tropopause (compared to higher altitudes in the lower stratosphere), especially for DCOTSS; vertical winds exhibit weaker sensitivity to convection and altitude during ACCLIP. The impact of gravity waves and turbulence on the variability in various trace gas species is also explored. Ultimately, this study aims to characterize small-scale vertical wind variability in the UTLS over the boreal monsoon regions, examine its relationship to potential sources like deep convection, and quantify its importance on UTLS composition.