Assessing Convective Influence by Utilizing Cloud to Ground Lightning Data and High Resolution Kinematic Trajectories
Abstract
One must understand the generation of NOx by lightning (LNOx) and its vertical redistribution by convection to quantify the atmospheric processing of reactive nitrogen species. This study addresses these themes by revisiting Jeker's concept of "lightning tracing" (Jeker et al., JGR, 2000) using INTEX-A data gathered from June to August 2004. Kinematic trajectories calculated with output from the National Weather Service's Rapid Update Cycle (RUC) model are initialized along several convectively influenced flights and then followed back to their most recent intersection with lightning flashes observed by the National Lightning Detection Network. Since the RUC data are hourly at a 20 km spacing, their resolution is much greater than usually available with global data. This procedure allows a meteorological assessment of the sample's age since convection, which then is compared to its observed chemistry. In addition, the influence of the most recent lightning encounter on the chemical data is contrasted to the influence of lightning accumulated along the entire back trajectory. Finally, an analysis of the number of flashes encountered along the trajectory provides a means to quantify LNOx production. Performing this "lightning tracing" over multiple flights spanning the entire troposphere allows the construction of a post-convective LNOx vertical profile for INTEX-A.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2005
- Bibcode:
- 2005AGUFM.A51D0097P
- Keywords:
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- 0365 Troposphere: composition and chemistry;
- 0368 Troposphere: constituent transport and chemistry;
- 3314 Convective processes;
- 3324 Lightning;
- 3329 Mesoscale meteorology