English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

This study investigates the origin of a commonly observed feature in theO3 profiles: mid tropospheric O3maxima (300--500 hPa) over the tropical Indian Ocean. Acomparison and analysis of model simulations, using a 3-D global climate-chemistrymodel, and measured O3profiles from the INDOEX campaign is presented. EuropeanCentre for Medium-Range Weather Forecast (ECMWF) meteorological analyses havebeen assimilated into the 3-D model to represent actual meteorology. The modelrealistically simulates the observed mid-tropospheric O3maxima. The analysis of themodel simulations shows that the major source of the mid-tropospheric O3 maxima isadvection of polluted air masses from continental biomass burning areas over Africa,with generally only a small contribution of stratospheric O3. Previous studies hinted atstratosphere-troposphere exchange (STE) along the subtropical jet (STJ) as theprimary source of the mid-tropospheric O3maxima over the Indian Ocean. Analysis of the model simulations shows that the mechanism causing themid-tropospheric transport of African biomass burning pollution and stratospheric airmasses are frontal zones or waves passing along the subtropical jets, causingadvection of tropical air masses in the prefrontal (equatorward) zone. Furthermore, thefrontal zones or waves also cause STE at the poleward side of the STJ. The modelsimulations also indicate that the contribution of STE in general is minor compared toadvection and in situ tropospheric production of O3for the mid-tropospheric O3budget over the Indian Ocean region

atmospheric chemistry and physics

On the origin of tropospheric O&amp;lt;sub&amp;gt;3&amp;lt;/sub&amp;gt; over the Indian Ocean during the winter monsoon: African biomass burning vs. stratosphere-troposphere exchange