Volatile Organic Compounds (VOCs) were collected in canister samples during NASA's Deriving Information on Surface conditions from COlumn and VERtically Resolved Observations Relevant to Air Quality (DISCOVER-AQ) mission in July 2011. Twenty three samples were collected at the surface and analyzed for OH reactivity, temporal variability, and relationships with atmospheric dynamics in an effort to have some insight into VOC behaviors at Edgewood, MD during a short period of time. Alkenes and oxygenated volatile organic compounds (VOCs) were the most abundant and the most reactive VOCs measured over the site. Source attribution of the measured species indicates that biogenically sourced VOCs account for half the calculated OH reactivity at the site. A case study of 2 days of canister samples and ozonesondes were used to investigate VOC dynamics over the site. A stable boundary layer present on 21 July prevented a lofted layer of pollution from mixing to the ground, causing relative anthropogenic VOC contributions to decrease, increasing the relative biogenic and oxygenated mixing ratios throughout the day. Mixing of the residual layer to the ground on 22 July enhanced the anthropogenic VOCs, and high temperatures increased biogenic emissions leading to a day that with high ozone and VOC measurements.
All Science Journal Classification (ASJC) codes
- Environmental Chemistry
- Atmospheric Science