Conceptual Study of Water Vapor and Bry Transport Across the Tropical Transition Layer
The process of water vapor transport across the tropical transition layer (TTL) combines slow advection with both microphysical and convective processes. The bromine budget of the stratosphere can not be reconciled with ground-based, balloon or satellite bromine monoxide (BrO) measurements using long-lived bromine containing substances alone. Much recent modeling work has invested the contribution of the very short- lived bromine substances bromoform (CHBr3) and combined with dibromomethane (CH2Br2) upon the stratospheric Bry budget. In this study we examine these very short lived (VSL) as well as long-lived bromine species including their interaction of the water vapor transport processes through the TTL. Lagrangian back trajectories initiated in the stratosphere are generated using ECMWF Interim reanalysis data. A convective parameterization using the ERA-Interim water vapor data is presented. A simplified microphysical and bromine chemical box model representation along the trajectories is used and the effect of convective processes explored. We present the transport of the VSL bromine in a conceptualized form and investigate sensitivities to the general chemical, microphysical and convective processes that result in VSL bromine contributing to the total stratospheric bromine budget.
Helmholtz Research Programs > PACES I (2009-2013) > TOPIC 1: The Changing Arctic and Antarctic > WP 1.2: Aerosol, Water Vapour, and Ozone Feedbacks in the Arctic Climate System