Transport and chemistry of formaldehyde by mesoscale convective systems in West Africa during AMMA 2006

摘要: [1] In situ measurements of formaldehyde (CH2O) onboard four European research aircraft in August 2006 as part the African Monsoon Multidisciplinary Analysis (AMMA) experiment West Africa are used (1) to examine redistribution CH2O by mesoscale convective systems (MCS) tropical upper troposphere (UT), (2) evaluate scavenging efficiency (SE) MCS and (3) quantify impact on UT photooxidant production downwind MCS. The intercomparison is first tested, providing a unique consistent 3-D-spatially resolved database background conditions. While carbon monoxide (CO) vertically uplifted deep convection up 12 km, also affected cloud processing seen from its ratio relative CO with altitude. A new observation-based model established SE CH2O. This shows that entrainment free tropospheric air cannot be neglected since it contributes 40% air. For 4 studied MCS, large variability within 4% 39% range at standard deviation 30%, which features. time-dependent photochemical box applied After convection, 60% due rather than direct transport. Model results indicate directly injected does not ozone HOx Africa. NOx anthropogenic hydrocarbon precursors dominate secondary CH2O, HOx.