AAAR 33rd Annual Conference
October 20 - October 24, 2014
Rosen Shingle Creek
Orlando, Florida, USA
Abstract View
Overview of the NOAA SENEX Field Mission
JOOST DE GOUW, Aikaterini Bougiatioti, Jerome Brioude, Steven G. Brown, William P. Dube, Peter Edwards, David Fahey, Jessica Gilman, Timothy Gordon, Martin Graus, Tom Hanisco, John Holloway, Jennifer Kaiser, Frank Keutsch, Daniel Lack, Daniel Law, Ben Lee, Brian Lerner, Jin Liao, Jack Lin, Felipe Lopez-Hilfiker, Milos Markovic, Ann M. Middlebrook, Kyung-Eun Min, et al., NOAA ESRL
Abstract Number: 157 Working Group: Air Quality and Climate in the Southeast US: Insights from Recent Measurement Campaigns
Abstract The NOAA Southeast Nexus of Air Quality and Climate Change (SENEX) study was focused on biogenic and anthropogenic emissions in the Southeastern United States, and their interactions to form oxidants and aerosol. For SENEX, the NOAA WP-3D research aircraft was deployed out of a regional airport in Smyrna, Tennessee during June and July of 2013. The aircraft carried an extensive suite of instruments to characterize the gas- and aerosol-phase composition of the atmosphere, as well as the climate-relevant properties of the aerosol. The SENEX study was performed in close collaboration with several other studies in the framework of the Southeast Atmosphere Study.
Some highlights of the measurements will be presented. Vertical distributions of aerosol, and gradients below, within and above clouds, were carefully examined for evidence of aqueous-phase chemistry. Measurements downwind from power plants gave insight into particle formation and growth into CCN-active size ranges. Power plant plumes over isoprene and monoterpene emitting regions yield insight into the formation of organic aerosol from biogenic precursors in air masses with enhanced NOx and SO2. Measurements over urban areas were used to study the formation of secondary organic aerosol from anthropogenic emissions. Organic aerosol correlated closely with CO and other species emitted from mobile sources. However, the enhancements in CO and organic aerosol downwind from major cities were small relative to a region-wide enhancement in these species explained from emissions in the eastern U.S. accumulated over many days. Nighttime flights were conducted to look for evidence of organic aerosol formation from the reaction between biogenic VOCs and nitrate radicals. Finally, agricultural fires in the Mississippi delta region were widespread during the mission and their emissions were sampled on two flights. The SENEX data will be useful to constrain the sources and climate-relevant properties of aerosol in the southeast U.S.