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

Observations of a comprehensive suite of inorganic and organic trace gases,including non-methane hydrocarbons (NMHCs), halogenated organics andoxygenated volatile organic compounds (OVOCs), obtained from the NASA DC-8over Canada during the ARCTAS aircraft campaign in July 2008 illustrate thatconvection is important for redistributing both long- and short-livedspecies throughout the troposphere. Convective outflow events wereidentified by the elevated mixing ratios of organic species in the uppertroposphere relative to background conditions. Several dramatic events wereobserved in which isoprene and its oxidation products were detected athundreds of pptv at altitudes higher than 8 km. Two events are studied indetail using detailed experimental data and the NASA Langley Research Center(LaRC) box model. One event had no lightning NOx (NO + NO2)associated with it and the other had substantial lightning NOx (LNOx > 1 ppbv). When convective storms transport isoprene from the boundarylayer to the upper troposphere and no LNOx is present, OH is reduceddue to scavenging by isoprene, which serves to slow the chemistry, resultingin longer lifetimes for species that react with OH. Ozone and PAN productionis minimal in this case. In the case where isoprene is convected andLNOx is present, there is a large effect on the expected ensuingchemistry: isoprene exerts a dominant impact on HOx andnitrogen-containing species; the relative contribution from other species toHOx, such as peroxides, is insignificant. The isoprene reacts quickly,resulting in primary and secondary products, including formaldehyde andmethyl glyoxal. The model predicts enhanced production of alkyl nitrates(ANs) and peroxyacyl nitrate compounds (PANs). PANs persist because of thecold temperatures of the upper troposphere resulting in a large change inthe NOx mixing ratios which, in turn, has a large impact on theHOx chemistry. Ozone production is substantial during the first fewhours following the convection to the UT, resulting in a net gain ofapproximately 10 ppbv compared to the modeled scenario in which LNOx ispresent but no isoprene is present aloft

Impact of the deep convection of isoprene and other reactive trace species on radicals and ozone in the upper troposphere