TY  - THES
AU  - Zheng, Siyuan
TI  - Investigation of Lower Boundary Conditions of Brominated Very Short-lived Species (VSLS)
VL  - 637
PB  - Wuppertal
VL  - Dissertation
CY  - Jülich
M1  - FZJ-2024-05235
SN  - 978-3-95806-770-7
T2  - Schriften des Forschungszentrums Jülich Reihe Energie & Umwelt / Energy & Environment
SP  - 2, iii, 160
PY  - 2024
N1  - Dissertation, Wuppertal, 2024
AB  - Photochemical reactions with the reactive halogen atoms Cl and Br mostly cause stratospheric ozone depletion. The chlorine- and bromine-containing very short-lived species (VSLS), which have an atmospheric lifetime of less than six months, play an essentialrole in stratospheric total bromine loading. However, there is considerable uncertainty about the geographical distribution of their sources, and therefore, it is challenging to reproduce the observations. In order to describe the stratospheric or regional abundance of bromine from VSLS, it is of great importance to quantify the lower boundary conditions of these species. In order to increase our understanding of the role of brominated species in the stratosphere, the Chemical Lagrangian Model of the Stratosphere (CLaMS) has been used to investigate the global surface mixing ratio and lower boundary conditions for the simulation in this thesis. The simulation uses a ‘top-down’ approach, where atmospheric measurements from aircraft are used in combination with models to quantify and refine the lower boundary emissions. Firstly, for the representation of tropospheric bromine chemistry, the scheme incorporates bromine-containing species and related chemical decomposition reactions into CLaMS, which include photolysis and reactions with Cl, O(1D), and OH. Using a box model, this chemistry scheme was successfully tested and transferred to the more comprehensive global 3D chemical transport model, MESSy-CLaMS.Secondly, for the representation of tropospheric bromine chemistry, a parameterization  for the washout of the inorganic bromine species HBr and HOBr in the troposphere by cloud uptake was incorporated. To enhance the representation of the transport  scheme, additional tropospheric mixing and vertical transport by convection were adopted employing the MESSy-CLaMS 2.0 version. Finally, to investigate the lower boundary conditions of the two most significant bromine VSLS, CHBr3 and CH2Br2, the CLaMS model constructed the zonal symmetric seasonal dependent lower boundary, the seasonal and monthly dependent regionally resolved lower boundary map
LB  - PUB:(DE-HGF)3 ; PUB:(DE-HGF)11
DO  - DOI:10.34734/FZJ-2024-05235
UR  - https://juser.fz-juelich.de/record/1030129
ER  -