An Investigation of High Frequency Motions in the Tropical Tropopause Layer near ConvectionIndirect evidence indicates a role for vertical mixing in the Tropical Tropopause Layer (TTL). In the past 20 years, high altitude NASA aircraft such as the ER-2, WB-57, and GLobal Hawk have been making 20hz measurements of vertical velocity and other meteorological parameters in the Upper Tropospere-Lower Stratosphere region, many in the tropics, most recently in connection with the Airborne Tropical TRopopause EXperiment (ATTREX). In the stable environment of the UTLS, high frequency activity occurs in bursts, presumably in connection with nearby convection or strong vertical shear associated with larger scale gravity waves. This paper examines tropical high frequency aircraft data to obtain some basic information about the distribution and character of high frequency activity in vertical velocity in the TTL. In particular, we focus on relating the high frequency activity to nearby tropical convection.
Document ID
20160008995
Acquisition Source
Ames Research Center
Document Type
Conference Paper
Authors
Pfister, Leonhard (NASA Ames Research Center Moffett Field, CA United States)
Bui, T. P. (NASA Ames Research Center Moffett Field, CA United States)
Dean-Day, Jon (Bay Area Environmental Research Inst. Moffett Field, CA, United States)
Lim, Boon (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Lawson, Paul (Spec, Inc. Boulder, CO, United States)