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Tropopause-Level NO_x in the Asian Summer Monsoon.

ABSTRACT: Deep convection within the Asian summer monsoon (ASM) transports surface level air into the upper troposphere-lower stratosphere (UTLS). This work aims to understand the distribution of NO₂, NO, and NO_x in the UTLS ASM anticyclone from satellite measurements. Observations of NO₂ from the Optical Spectrograph and InfraRed Imager System, the Atmospheric Chemistry Experiment - Fourier Transform Spectrometer (ACE-FTS), and the Stratospheric Aerosol and Gas Experiment III on the International Space Station are considered. The PRATMO photochemical box model is used to quantify the NO_x photochemistry, and to derive the NO_x concentration using OSIRIS NO₂ and O₃ observations. The satellite data show a relative minimum in NO₂ over the ASM in the summer months, while the corresponding NO and NO_x anomalies are elevated, mainly due to low O₃ and cold temperatures within the ASM. The observations within the ASM show reasonable agreement to simulations from the Whole Atmosphere Community Climate Model.

SUBMITTER: Dube K

PROVIDER: S-EPMC9539711 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature

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Tropopause-Level NOx in the Asian Summer Monsoon.

Dubé Kimberlee K Randel William W Bourassa Adam A Degenstein Doug D

Geophysical research letters 20220914 18

Deep convection within the Asian summer monsoon (ASM) transports surface level air into the upper troposphere-lower stratosphere (UTLS). This work aims to understand the distribution of NO2, NO, and NOx in the UTLS ASM anticyclone from satellite measurements. Observations of NO2 from the Optical Spectrograph and InfraRed Imager System, the Atmospheric Chemistry Experiment - Fourier Transform Spectrometer (ACE-FTS), and the Stratospheric Aerosol and Gas Experiment ...[more]

PMID: 36246737

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