Evidence of a LNOX influence on middle/upper troposphere ozone-mixing ratios at Dakar, Senegal during Northern Hemisphere summer season
We present results for the vertical distribution of tropospheric ozone from 40 measurements at Dakar, Senegal (14.59?N, 17.5?W) from June to September of 2008, 2010, 2011 and 2012. Under pre-monsoon conditions (June), many dry air intrusions are found in the lower troposphere transitioning to humid conditions during July, August and September.
Measurements show the highest ozone-mixing ratios (50–100 ppb) in the 400–200 hPa layer and easterly wind flow during each month. Lightning-NOX (LNOX) is the only viable source to explain the vertical distribution of ozone, with a large amount of upstream lightning over West Africa during summer.
Auteur(s) : Gregory S. Jenkins, Moussa Gueye, Mamadou S. Drame and Seydi A. Ndiaye
Pages : 195–203
Année de publication : 2014
Revue : Atmospheric Science Letters
N° de volume : 15
Type : Article
Mise en ligne par : NDIAYE Seydi Ababacar