INVESTIGADORES
FERNANDEZ Rafael Pedro
artículos
Título:
Modeling the Sources and Chemistry of Polar Tropospheric Halogens (Cl, Br, I) using the CAM‐Chem Global Chemistry‐Climate Model
Autor/es:
FERNANDEZ, RAFAEL P.; CARMONA-BALEA, ANTÍA; CUEVAS, CARLOS A.; BARRERA, JAVIER A.; KINNISON, DOUGLAS E.; LAMARQUE, JEAN?FRANCOIS; BLASZCZAK?BOXE, CHRISTOPHER; KIM, KITAE; CHOI, WONYONG; HAY, TIMOTHY; BLECHSCHMIDT, ANNE?MARLENE; SCHÖNHARDT, ANJA; BURROWS, JOHN P.; SAIZ-LOPEZ, ALFONSO
Revista:
Journal of Advances in Modeling Earth Systems
Editorial:
American Geophysical Union (AGU)
Referencias:
Año: 2019
ISSN:
1942-2466
Resumen:
Current chemistry climate models do not include polar emissions and chemistry of halogens. This work presents the first implementation of an interactive polar module into the very short-lived (VSL) halogen version of the CAM-Chem model. The polar module includes photochemical release of molecular bromine, chlorine and interhalogens from the sea-ice surface, and brine diffusion of iodine biologically produced underneath porous sea-ice. It also includes heterogeneous recycling of inorganic halogen reservoirs deposited over fresh sea-ice surfaces and snow covered regions. The polar emission of chlorine, bromine and iodine reach approximately 32, 250 and 39 Gg yr−1 for Antarctica and 33, 270 and 4 Gg yr−1 for the Arctic, respectively, with a marked seasonal cycle mainly driven by sunlight and sea-ice coverage. Model results are validated against polar boundary layer measurements of ClO, BrO and IO, and satellite BrO and IO columns. This validation includes satellite observations of IO over inner Antarctica for which an iodine ?leapfrog? mechanism is proposed to transport active iodine from coastal source regions to the interior of the continent. The modeled chlorine and bromine polar sources represent up to 45 and 80% of the global biogenic VSLBr and VSLCl emissions, respectively, while the Antarctic sea-ice iodine flux is ~10 times larger than that from the Southern Ocean. We present the first estimate of the contribution of polar halogen emissions to the global tropospheric halogen budget. CAM-Chem includes now a complete representation of halogen sources and chemistry from pole-to-pole and from the Earth?s surface up to the stratopause.